Taxonomic revision of the Pheidole sikorae species group (Hymenoptera, Formicidae) from Madagascar

Abstract The present study represents a taxonomic revision of the Pheidole sikorae species group from Madagascar. Forty-four members of this group are recognised and described, and an illustrated identification key to this group is also presented. One species is raised to species level: P. litigiosa Forel, 1892 stat. nov.Pheidole veteratrix angustinoda Forel, 1892 syn. nov. is proposed as a junior synonym of Pheidole veteratrix Forel, 1891. Worker castes are also described and lectotypes designated for P. litigiosa Forel, 1892, P. sikorae Forel, 1891, and P. veteratrix Forel, 1891. The following 41 new species are described: P. alinasp. nov., P. ambohimangasp. nov., P. analavelonasp. nov., P. andohahelasp. nov., P. anomalasp. nov., P. anosyennesp. nov., P. antranohofasp. nov., P. beankasp. nov., P. befotakasp. nov., P. dasossp. nov., P. flavominutasp. nov., P. gracilissp. nov., P. habokasp. nov., P. havoanasp. nov., P. hazosp. nov., P. itremosp. nov., P. joffrevillesp. nov., P. kelysp. nov., P. lavasoasp. nov., P. mahamavosp. nov., P. maintysp. nov., P. mamiratrasp. nov., P. mananteninasp. nov., P. masoandrosp. nov., P. mavohavoanasp. nov., P. midongysp. nov., P. mikrossp. nov., P. mivorysp. nov., P. nitidobrunasp. nov., P. parvulasp. nov., P. parvulogibbasp. nov., P. reniranosp. nov., P. savasp. nov., P. sofiasp. nov., P. sparsasp. nov., P. tamponysp. nov., P. trichotossp. nov., P. tsaravonianasp. nov., P. vadumsp. nov., P. volontanysp. nov., and P. vonysp. nov. At present, there are 109 valid species and subspecies of Pheidole known from Madagascar, but this number is expected to increase with upcoming taxonomic revisions of the species groups not revised in this study.


Introduction
The hyper-diverse ant genus Pheidole Westwood, 1839, with 1,095 species and 132 subspecies, is the second most species-rich ant genus in the world (Bolton 2020). Its centre of distribution is located in the Neotropical region, which hosts nearly 50% of known Pheidole taxa. The other zoogeographical regions hold distinctly fewer number of species: Oceania -20, Palearctic -22, Nearctic -79, Australasia -110, Afrotropic -139, and Indomalaya -146 (Bolton 2020). However, knowledge of the taxonomy and diversity of Pheidole is far from complete and a significant increase in the number of taxa can be expected in a poorly studied region such as the Afrotropic (Fischer et al. 2012). The Malagasy Pheidole had been neglected for decades until recent papers published by Fischer and Fisher (2013) and Salata and Fisher (2020). Fischer and Fisher (2013) provided the first comprehensive review of Pheidole known from the small Malagasy Region islands. They summarised hitherto known data on their diversity and described the presence of 13 species, seven of which were considered as endemic. However, their work did not cover Madagascar, the largest Malagasy island, recognised by Fisher and Peeters (2019) as having exceptionally diverse and abundant Pheidole fauna.
Taxonomic research published by Salata and Fisher (2020) ended a 100 year-long break in studies on this genus from Madagascar. They proposed the first species-group division, revised eleven species groups, redescribed six species, and described 46 species new to science. Their study increased the number of known Pheidole from 20 to 69, of which 67 are considered endemic. However, they estimated that the number of species will increase with taxonomic work on the following five species groups: sikorae, bessonii, fervens, megacephala, and lucida.
In this study, we present a revision of the sikorae species group, which appears to be the most species-rich on Madagascar. As mentioned in Salata and Fisher 2020, our species-group division is based on morphological similarities and their monophyly will be addressed in further studies. The sikorae group contains 44 species and its members are known exclusively from the island. Three species, P. litigiosa Forel, P. sikorae Forel, and P. veteratrix Forel, are already described members of the group. An additional 41 taxa are described here as new to science. This work increases the total number of species of Madagascar Pheidole to 109 (106 species endemic to the island) and ranks this genus as the second most species-rich on the island. The number of valid Pheidole taxa from the Malagasy region is estimated at 119, making this bioregion the fourth most species-rich globally.

Materials and methods
The majority of the material was collected by BLF and members of the Madagascar Biodiversity Centre from across Madagascar between 1991 and 2018. We included also material deposited in the Museum d'Historie Naturelle, Geneva, Switzerland.
Repositories. Collections are referred to by the following acronyms: All observations and measurements were taken using a pin-holding stage, permitting rotations around the X, Y, and Z axes at magnifications from 32× to 100× with a Leica MZ12.5 microscope and an orthogonal crosshair micrometre, at an accuracy of 0.01 mm to approximately 0.005 mm. All measurements are presented in mm units as minimum and maximum values, with the arithmetic mean in parentheses. Photographs were taken using a JVC KY-75 or Leica DFC450 digital camera with a Leica Z16 APO microscope and Leica Application Suite software (v3.8). Unless stated otherwise, photographs were taken by Michele Esposito. Images of specimens and data of all pinned specimens examined in the present contribution are available online on AntWeb (www.AntWeb.org) and accessible using the unique CASENT identifying specimen code. Measurements and indices are in line with Salata and Fisher (2020) and are predominantly the same as in Longino (2009Longino ( , 2019 and several other revisions (Eguchi 2008;Fischer et al. 2012;Fischer and Fisher 2013;Wang et al. 2018). The general morphological terminology follows Wilson (2003) and Longino (2009Longino ( , 2019. Additionally, in both majors and queens of Pheidole sikorae, we observed an impressed and smooth concavity present lateral to the antennal socket and the tentorial pit (Figs 14E,53B,D). The concavity is separated from the antennal socket by a distinct ridge. We cannot consider these structures as reduced antennal scrobes because: a) they do not accommodate the basal part of the scape, which is always distinctly convex, and b) they extend anteriorly towards the posterior margin of clypeus. To our knowledge, this morphological feature is found exclusively in majors and queens of P. sikorae.
As older taxa are often insufficiently characterised by their original describers, diagnoses are provided in the redescriptions for P. litigiosa Forel, 1892, P. sikorae Forel, 1891, and P. veteratrix Forel, 1891 to make identifications easier.
Our recognition of species follows the biological species concept and species boundaries are based on comparative morphology and known geographic distribu-

Synopsis of species of the Pheidole sikorae group
Pheidole alina sp. nov. Pheidole

Species accounts
Repetitive characters occurring in the majority of species have been omitted. Unless stated otherwise, the following descriptions apply to all species treated here.
Major workers. Dorsal face of head in lateral view not depressed posteriorly; antennal sockets shallow; frontal lobes absent; head in full-face view with distinct median concavity; antenna 12-segmented, with 3-segmented club; masticatory margin of mandible with large, stout apical and preapical teeth, followed by a long diastema and then a short and crenulate tooth just before the rounded basal angle; outer surface of mandible mostly smooth and shining, sometimes with weak and sparse foveolae; antennal scrobes absent; promesonotum strongly convex, well above the level of propodeum; petiolar peduncle with small horizontal lobes on its basal part; postpetiole short with slightly convex dorsum; petiolar peduncle without horizontal lobes on its basal part; body unicolourous.
Minor workers. Antennal sockets shallow; frontal lobes absent; occipital carina absent; head in full-face view oval, posterior and anterior of eyes convex; antenna 12-segmented, with 3-segmented club; humeral area not developed; clypeus smooth and shiny, its anterior margin regularly convex; promesonotum well above the level of propodeum; petiole smooth, with node moderately low, triangular, and small, with few short, erect setae; petiolar peduncle with ventral face slightly convex; postpetiole smooth, short, low, and slightly convex, with few short, erect setae; gaster smooth and shiny; body unicolourous.

29
Major workers. Body brownish black, base of first gastral tergite shagreened (Fig. 12B, G). Minor workers. Mesosoma distinctly foveolate, body dark brown (Fig. 12E) (Fig. 12C, H). Minor workers. Body yellowish brown to brown, if dark brown then katepisternum at least with smooth notch (Fig. 12F)  Major workers. Impressed and smooth concavity placed lateral to antennal socket and tentorial pit present (Fig. 14E). Minor workers. Body yellow to orange, head always with reduced sculpture, mesosomal dorsum with few transverse, thick rugulae and propodeum with indistinct and sparse foveolae, propodeal spines very small, triangular, promesonotal groove present, promesonotum moderately high, short (15E, J) .................. Pheidole sikorae Forel -Major workers. Impressed and smooth concavity placed lateral to antennal socket and tentorial pit absent 16). Minor workers. Combination of characters different 18 Major workers. Head in full-face view widening posteriorly, with lateral sides distinctly convex ( Fig. 14A-D). Minor workers. Body brown to dark brown, head predominantly foveolate, mesosoma predominantly smooth and propodeal spines minute or body yellow to orange, promesonotal groove deep, mesosoma predominantly or entirely smooth ( Fig. 15A-D, F-I) ..............34 -Major workers. Head in full-face view not widening posteriorly, with lateral sides relatively straight or slightly convex (Fig. 16). Minor workers. Body brown to dark brown, head predominantly foveolate and mesosoma foveolate with smooth notch on katepisternum or mesosoma predominantly smooth and propodeal spines moderate or body yellow to orange, promesonotal groove absent or indistinct, if present then mesosoma with distinct foveolae (Fig. 18)  Major workers. Head in full-face view sub-oval and elongate with lateral sides slightly convex and narrowing posteriorly, medial frons with sparse, interrupted, and longitudinal rugae with predominantly smooth interspaces, lateral sides of frons with dense, irregular rugae with distinctly foveolate interspaces (Fig. 16E, G). Minor workers. Promesonotal groove present but indistinct, body yellowish brown and head and mesosoma entirely or predominantly smooth or body brown and head with sparse foveolae and smooth notches on frons and mesosoma with sparse and indistinct foveolae with smooth notches on dorsum and anepisternum and katepisternum (Fig. 18E, G, N, P) ......38 -Major workers. Head in full-face view sub-oval but not elongate with lateral sides relatively straight or slightly convex but never narrowing posteriorly, medial frons with dense, sometimes interrupted and longitudinal rugae with predominantly sculptured interspaces, lateral sides of frons with dense to sparse longitudinal to longitudinally irregular rugae with interspaces smooth to rugoreticulate or rugofoveolate ( Major workers. Medial part of frons with interspaces finely foveolate, lateral sides with more longitudinally irregular rugae, body ferruginous, promesonotum never with reduced sculpture (Figs 16G,17F). Minor workers. Head predominantly smooth or foveolae with foveola sparse and fading on medial frons and area posterolateral from eyes; vertex with sparse and short rugulae; frons with very sparse, short, and irregular rugae; mesosoma with sparse rugofoveolae; promesonotal dorsum and katepisternum with smooth notches or smooth; pronotum with additional sparse, short, and transverse rugulae ( Major workers. Medial part of frons with smooth or indistinct rugofoveolae, lateral sides of frons with rugae predominantly irregular, body brownish to dark orange, promesonotum with reduced sculpture (Figs 16E,17E). Minor workers. Head predominantly smooth; frons with longitudinal, short, and thick rugae and sometimes foveolate interspaces, promesonotum predominantly smooth (Fig. 18E, N
Diagnosis. Moderately large species. Major workers. Head in full-face view suboval and slightly widening posteriorly, with anterior and posterior sides slightly convex, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with moderately dense, long, suberect to erect pilosity; medial part of frons with thick, interrupted, dense, and longitudinal rugae with smooth to indistinctly rugulate interspaces; occipital lobes and area posterolateral from eyes without smooth notches; scape, when laid back, exceeding the midlength of head by one-fifth of its length; inner hypostomal teeth indistinct, low, and wide, closely spaced, bulge-like; outer hypostomal teeth lobe-like, wider and higher than inner teeth, apex directed upward; inner and outer hypostomal teeth closely spaced and not connected by concavity; mesosoma rugofoveolate; pronotum with additional thin, moderately dense, and transverse rugae; katepisternum with reduced sculpture and sometimes with smooth notch; gaster smooth; body black. Minor workers. Head foveolate; median frons with short, indistinct, and longitudinal rugulae; area posterolateral from eyes with slightly to distinctly weaker sculpture; scape, when laid back, exceeding the posterior head margin by onethird of its length; promesonotum low and moderately long; promesonotal groove present; propodeal spines small and triangular; mesosoma foveolate; katepisternum with reduced sculpture or with smooth notch; body black to dark brown.
Etymology. Malagasy for night in reference to dark body colouration. Biology. The species was collected between 1270-2000 m in elevation, in montane rainforest and montane shrubland. Nests were located in rotten logs, under moss above and on the ground, and in a Melastomataceae twig.
Comments. Pheidole alina sp. nov. belongs to the group of taxa characterised by dark body colouration, in major workers from brownish black to black and in minor workers from black (head and mesosoma) to dark brown with body predominantly foveolate (in dark brown specimens entirely). The group consists of three species: P. alina sp. nov., P. trichotos sp. nov., and P. mainty sp. nov. All members of this group are sympatric and their distribution is limited to northernmost parts of the island, predominantly in Antsiranana prefecture. Major workers of Pheidole alina sp. nov. differ from P. trichotos sp. nov. by medial part of frons with thick, interrupted, dense, and longitudinal rugae with smooth to indistinctly rugulate interspaces, base of first gastral tergite smooth and indistinct, bulge-like inner hypostomal teeth; from P. mainty sp. nov. in sides of the head with moderately dense, long, suberect to erect pilosity, indistinct, bulge-like inner hypostomal teeth, and narrow and moderately long propodeal spines. Minor workers of P. alina sp. nov. differ from P. trichotos sp. nov. in larger body size and black body colouration; from P. mainty sp. nov. in never entirely smooth area posterolateral from eyes and distinctly foveolate mesosoma with reduced or no foveolae only on the katepisternum.  (CASC).
Diagnosis. Moderately large species. Major workers. Head in full-face view oval, not widening posteriorly, with anterior and posterior sides convex, in lateral view sub-oval, ventral and dorsal faces convex, occipital cleft moderately deep; sides of the head with dense, very long, erect pilosity; medial part of frons with thick, moderately sparse, and irregular rugae, interspaces predominantly smooth and sometimes with indistinct rugulae; lateral sides of head, area posterolateral from eyes and occipital lobes with relatively dense to dense, thick, and irregular rugae; interspaces predominantly smooth or indistinctly rugulate; scape, when laid back, exceeding the midlength of head by two-fifths of its length; inner hypostomal teeth distinct, large, closely spaced, and triangular, with rounded apex directed inward; outer hypostomal teeth lobe-like, slightly wider than inner hypostomal teeth and approximately the same height, apex directed outward; inner and outer hypostomal teeth closely spaced and not connected by concavity; lateral sides of pronotum, mesonotum, katepisternum, anepisternum, and propodeum rugofoveolate, pronotal dorsum with thick to thin, irregular to transverse rugae with smooth to indistinctly rugofoveolate interspaces; katepisternum with smooth notch; body dark brown. Minor workers. Head with sparse foveolae; frons with foveolae reduced medially with moderately thick, longitudinal, and interrupted rugae; area posterolateral from eyes with reduced sculpture, predominantly smooth; scape, when laid back, surpassing the posterior head margin by two-fifths of its length; promesonotum moderately high and short; promesonotal groove absent; propodeal spines minute and triangular; propodeum predominantly smooth, its dorsum with sparse, short, and transverse rugae and indistinct foveolae; mesonotum, anepisternum, katepisternum, and propodeum predominantly smooth, with sparse and indistinct foveolae on anterolateral and anterior sides; body brown. Head. In full-face view oval, not widening posteriorly, with anterior and posterior sides convex (Fig. 20B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with dense, very long, erect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with thick, moderately sparse, irregular rugae, interspaces predominantly smooth and sometimes with indistinct rugulae; lateral sides of head, area posterolateral from eyes, and occipital lobes with relatively dense to dense, thick, and irregular rugae; interspaces predominantly smooth or indistinctly rugulate. Gena with relatively dense, thick, and longitudinal rugae and smooth interspaces. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina present; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by two-fifths of its length; pilosity subdecumbent to erect (Fig. 20B, D). Inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed inward; outer hypostomal teeth lobe-like, slightly wider than inner hypostomal teeth and approximately the same height, apex directed out-ward; inner and outer hypostomal teeth closely spaced and not connected by concavity (Fig. 63B). Mesosoma. In lateral view, promesonotum short, angular, and moderately low, posterior mesonotum moderately steep, mesonotal process distinct, tubercle-like; promesonotal groove absent; metanotal groove absent; propodeal spines moderately short, with wide base and acute apex; humeral area laterally weakly produced (Fig.  20D). Surface shiny; lateral sides of pronotum, mesonotum, katepisternum, anepisternum, and propodeum rugofoveolate, pronotal dorsum with thick to thin, irregular to transverse rugae with smooth to indistinctly rugofoveolate interspaces; katepisternum with smooth notch. Pilosity moderately dense, long, and erect (Fig. 20D, F). Petiole. Shiny with fine foveolae; node smooth to finely foveolate, low, triangular, with rounded and thin apex, in rear view node dorsoventrally straight to slightly convex; pilosity moderately sparse and erect (Fig. 20D, F). Postpetiole. Shiny and foveolate; dorsum with reduced sculpture and smooth notch; in dorsal view oval, lateral margins medially with two dentate projections; pilosity long, moderately sparse, and erect ( Head. Cephalic margin indistinctly concave or straight (Fig. 20A). Pilosity relatively sparse, long, decumbent to suberect. Sculpture shiny with sparse foveolae; frons with foveolae reduced medially with moderately thick, longitudinal, and interrupted rugae; area posterolateral from eyes with reduced sculpture, predominantly smooth; antennal sockets with few thick, curved outward rugae and indistinctly foveolate interspaces. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, surpassing the posterior head margin by two-fifths of its length; pilosity dense, subdecumbent to erect (Fig. 20A,C). Mesosoma. In lateral view, promesonotum moderately high and short, arched; promesonotal groove absent; metanotal groove distinct; propodeal spines minute and triangular (Fig. 20C). Sculpture shiny; propodeum predominantly smooth, its dorsum with sparse, short, transverse rugae and indistinct foveolae; mesonotum, anepisternum, katepisternum, and propodeum predominantly smooth, with sparse and indistinct foveolae on anterolateral and anterior sides. Pilosity moderately dense, long, and erect (Fig. 20C, E). Gaster. With sparse, erect pilosity (Fig. 20C, E). Colour. Brown, legs slightly brighter (Fig. 20C, E).
Etymology. From the type locality. Biology. The species was collected between 1294-1460 m in elevation, in rainforest, montane rainforest and park. Nests were located under rootmat on rock, in the soil, and in rotten logs.
Comments. Pheidole ambohimanga sp. nov. is a member of the group of species characterised by major workers with head in full-face view oval and not widening posteriorly and medial part of frons with thick, moderately sparse, irregular rugae or me- dial frons with moderately dense, thin, longitudinal anteriorly to irregular posteriorly, interrupted rugae and very shallow occipital cleft. Minor workers of this group have short and moderately high promesonotum and dark body colouration ranging from orange to brown. The group consists of three species: P. vadum sp. nov., P. analavelona sp. nov., and P. ambohimanga sp. nov. Pheidole ambohimanga sp. nov. is sympatric with P. vadum sp. nov. but morphologically is most similar to P. analavelona sp. nov. It can be easily separated from P. vadum sp. nov. based on thicker and exclusively irregular rugae on frons, deeper occipital cleft in majors, and presence of additional rugae on head in minors. Majors of P. ambohimanga sp. nov. can be distinguished from P. analavelona sp. nov. based on smooth to very indistinctly rugoreticulate interspaces on head, while minor workers have head sculpture foveolae strongly reduced to absent on frons, predominantly smooth area posterolateral from eyes, and mesonotum, anepisternum, katepisternum, and propodeum predominantly smooth, with sparse and indistinct foveolae on anterolateral and anterior sides. Minors of P. ambohimanga sp. nov. can be easily separated from other members of the sikorae group based on short and moderately high promesonotum and additional, moderately thick to thick, longitudinal, and interrupted rugae on head.  -22.64333, 44.17167;alt. 1300 m;.; montane rainforest, ex rotten log; BLF07953 (CASC). • 1w., 1s.; ibid.; BLF07966 (CASC). • 3., 3s.; ibid.; BLF07971 (CASC). • 6w., 1s., 1q., 6m.; ibid.; BLF07989 (CASC).
Diagnosis. Moderately large species. Major workers. Head in full-face view oval, not widening posteriorly, with anterior and posterior sides convex, in lateral view sub-oval, ventral and dorsal faces convex, occipital cleft moderately deep; sides of the head with dense, very long, suberect to erect pilosity; frons with thick, irregular rugae, moderately dense on lateral sides and sparser on medial part; interspaces shiny with distinct and sparse rugoreticulae; occipital lobes, area posterolateral from eyes never smooth; scape, when laid back, exceeding the midlength of head by one-fifth of its length; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed inward; outer hypostomal teeth lobe-like, wider than inner hypostomal teeth and approximately the same height, apex directed outward; inner and outer hypostomal teeth not closely spaced and not connected by concavity; mesosoma with dense rugofoveolae; pronotum, mesonotum, katepisternum, and anepisternum with additional thick to thin, irregular to transverse ru-gae; body dark brown. Minor workers. Head foveolate; medial frons with foveolae sparser and with moderately thick longitudinal and interrupted rugae; lateral sides of frons and vertex with additional moderately thick rugae; area posterolateral from eyes with reduced sculpture and smooth notches; scape, when laid back, surpassing the posterior head margin by two-fifths of its length; promesonotum moderately high and short; promesonotal groove absent; propodeal spines minute and triangular; propodeum predominantly smooth with indistinct rugofoveolae on lateral sides; mesonotum, anepisternum, katepisternum, and propodeum with sparse and indistinct rugofoveolae; body dark orange.
Etymology. From the type locality. Biology. The species was collected between 1100-1300 m in elevation, in montane rainforest. Nests were located in rotten logs and under stones.
Comments. Pheidole analavelona sp. nov. is a member of the group of species characterised by major workers with head in full-face view oval and not widening posteriorly and medial part of frons with thick, moderately sparse, and irregular rugae or medial frons with moderately dense, thin, longitudinal anteriorly to irregular posteriorly, and interrupted rugae and very shallow occipital cleft. Minor workers of this group have short and moderately high promesonotum and dark body colouration ranging from orange to brown. The group consists of three species: P. vadum sp. nov., P. analavelona sp. nov., and P. ambohimanga sp. nov. Pheidole analavelona sp. nov. is known from Forêt Classée d'Analavelona in Toliara and its distribution does not overlap with that of the two remaining members of the group known from the vicinity of Antananarivo. Morphologically both minor and major workers of P. analavelona sp. nov. are most similar to P. ambohimanga sp. nov. Majors of P. analavelona sp. nov. can be distinguished based on distinctly rugoreticulate interspaces on head while minor workers have head sculpture foveolate with foveolae sparser on frons and area posterolateral from eyes, and sparse but never absent rugofoveolae on mesonotum, anepisternum, katepisternum, and propodeum. Minors of P. analavelona sp. nov. can be easily separated from other members of the sikorae group based on short and moderately high promesonotum and additional, moderately thick to thick, longitudinal, and interrupted rugae on head.  (CASC). Paratype. • 1w.; same data as for holotype, CASENT0923281 (CASC).
Diagnosis. Minute species. Major workers. HL < 0.95 mm and WL < 0.8 mm; head in full-face view sub-oval; body dark brown; sides of head with very dense, relatively short, suberect pilosity; entire head distinctly sculptured; scape, when laid back, exceeding the midlength of head by two-fifths of its length; inner hypostomal teeth distinct, large, with sharp apex; outer hypostomal teeth lobe-like with apex directed distinctly outward; inner and outer hypostomal teeth not closely spaced and not connected by concavity. Minor workers. HL < 0.5 mm and WL < 0.6 mm, scape, when laid back, surpassing the posterior head margin by two-fifths of its length, propodeal spines reduced to small lobes, head elongate and oval and body dark brown; head sculpture shiny and predominantly smooth, vertex and frons with sparse, short, and transverse rugulae; anterolateral sides of propodeum and anepisternum with indistinct and sparse rugoreticulae.

Pheidole anomala
Diagnosis. Moderately large species. Major workers. Head in full-face view suboval and slightly widening posteriorly, with anterior and posterior sides slightly convex, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with dense, long, suberect to erect pilosity; medial part of frons with irregular and dense rugae, interspaces distinctly rugulate; occipital lobes, and area posterolateral from eyes without smooth notches; scape, when laid back, exceeding the midlength of head by one-fifth of its length; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed inward; outer hypostomal teeth lobe-like, wider than and approximately as high as inner teeth; inner and outer hypostomal teeth closely spaced and not connected by concavity; mesosoma rugofoveolate; gaster smooth; body ferruginous. Minor workers. Head foveolate; vertex with a few arcing, sparse, and moderately thick rugae; scape, when laid back, exceeding the posterior head margin by one-third of its length; promesonotum very low and moderately long; promesonotal groove absent; propodeal spines small, triangular; mesosoma foveolate; body yellow. Head. In full-face sub-oval, widening posteriorly, with anterior and posterior sides convex (Fig. 23B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with dense, long, suberect to erect pilosity; whole head with dense, long, decumbent to erect pilosity. Frons with thick, irregular, and dense rugae, interspaces distinctly rugulate. Occipital lobes with slightly thinner, dense, and irregular rugae and rugulate interspaces. Area posterolateral from eyes with dense rugoreticulae. Gena with relatively sparse and thick, longitudinal rugae with distinctly rugofoveolate interspaces. Centre of clypeus with sparse foveolae and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina present; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by one-fifth of its length; pilosity subdecumbent to erect (Fig. 23B, D). Inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed inward; outer hypostomal teeth lobelike, wider than and approximately as high as inner teeth; inner and outer hypostomal teeth closely spaced and not connected by concavity (Fig. 63E). Mesosoma. In lateral view, promesonotum short, angular, and moderately low, posterior mesonotum moderately steep, mesonotal process indistinct, tubercle-like; promesonotal groove absent; metanotal groove absent; propodeal spines moderate, with wide base and acute apex; humeral area produced (Fig. 23D). Surface shiny and rugofoveolate. Pilosity moderately dense, long, and erect (Fig. 23D, F). Petiole. Shiny with dense foveolae; node finely foveolate, triangular, with rounded and thick apex, in rear view node dorsoventrally slightly convex; pilosity moderately sparse and erect (Fig. 23D, F). Postpetiole. Shiny and foveolate; dorsum with reduced sculpture and smooth notch; in dorsal view oval, lateral margins medially with two dentate projections; pilosity long, moderately sparse, and erect (Fig. 23D, F). Gaster. Shiny and smooth; pilosity moderately dense, long, and erect (Fig. D, F). Colour. Ferruginous with yellowish legs (Fig. 23D, F).  Head. Cephalic margin slightly convex (Fig. 23A). Pilosity relatively sparse, moderately long, subdecumbent to erect. Sculpture shiny and foveolate; vertex with a few arcing, sparse, and moderately thick rugae; antennal sockets with few indistinct, curved outward rugae and foveolate interspaces. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, exceeding the posterior head margin by one-third of its length; pilosity dense, subdecumbent to erect (Fig. 23A, C). Mesosoma. In lateral view, promesonotum very low and moderately long, arched; promesonotal groove absent; metanotal groove distinct; propodeal spines small, triangular (Fig. 23C). Sculpture shiny and foveolate. Pilosity very sparse, moderately long, and erect (Fig. 23C, E). Gaster. With sparse, erect pilosity (Fig. 23C, E). Colour. Yellow, legs brighter (Fig. 23C, E).
Etymology. Latin for irregular in reference to strongly irregular rugae on frons of major workers.
Biology. The species was collected at 1135 m in elevation, in montane rainforest. Nest was located in a rotten log.
Comments. Pheidole anomala sp. nov. is most similar to P. veteratrix Forel, a widespread species known from Antananarivo north to Taolagnaro, and sympatric P. trichotos sp. nov. Major workers of P. anomala sp. nov. differ from both taxa in ferruginous body colouration and distinctly rugulate interspaces on frons; minor workers are easy to distinguish based on their bright yellow body colouration and entirely foveolate katepisternum.  (CASC). Paratype. • 1w.; same data as for holotype; CASENT0704255 (CASC).

Pheidole anosyenne
Diagnosis. Moderately large species. Major workers. Head in full-face view suboval and slightly widening posteriorly, with anterior and posterior sides slightly convex, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with moderately dense, short, decumbent to subdecumbent pilosity; anteromedial part of frons with moderately dense and thick, longitudinal rugae, posteromedial part with irregular rugae, interspaces with sparse and distinct rugofoveolae; occipital lobes, and area posterolateral from eyes without smooth notches; scape, when laid back, exceeding the midlength of head by approximately one-fifth of its length; inner hypostomal teeth distinct, moderate, closely spaced, triangular, with rounded apex and relatively narrow base; outer hypostomal teeth lobe-like, wider, and higher than inner hypostomal teeth, apex directed forward; inner and outer hypostomal teeth closely spaced and connected by indistinct concavity; mesosoma with fine rugofoveolae, dorsal and lateral sides of pronotum with additional transverse and thin rugae; gaster smooth; body ochreous. Minor workers. Head foveolate with additional indistinct longitudinal rugulae on medial frons, area posterolateral from eyes with reduced sculpture; scape, when laid back, surpassing the posterior head margin by two-fifths of its length; promesonotum moderately high and long, arched; promesonotal groove present; propodeal spines very small, triangular; mesosomal dorsum rugofoveolate; lateral sides of pronotum foveolate, anepisternum and katepisternum smooth, lateral sides of propodeum with smooth notches; body dark orange. Head. In full-face view sub-oval, widening posteriorly, with anterior and posterior sides convex (Fig. 24B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with moderately dense, short, decumbent to subdecumbent pilosity; whole head with relatively dense, short, decumbent to erect pilosity. Anteromedial part of frons with moderately dense and thick, longitudinal rugae, posteromedial part with irregular rugae, interspaces with sparse and distinct rugofoveolae; lateral sides with irregular and thick rugae with distinctly rugofoveolate interspaces. Occipital lobes with thick, sparse, irregular rugae, interspaces smooth or with fine, indistinct rugulae. Gena with sparse and thick, longitudinal rugae and indistinctly rugofoveolate interspaces. Area posterolateral from eyes with dense and thin rugofoveolae. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, wide, and shallow; median longitudinal carina present; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by approximately one-fifth of its length; pilosity decumbent to suberect (Fig. 24B, D). Inner hypostomal teeth distinct, moderate, closely spaced, triangular, with rounded apex and relatively narrow base; outer hypostomal teeth lobe-like, wider and higher than inner hypostomal teeth, apex directed forward; inner and outer hypostomal teeth closely spaced and connected by indistinct concavity (Fig. 63F). Mesosoma. In lateral view, promesonotum short, angular, and moderately high, posterior mesonotum moderately steep, mesonotal process indistinct, tubercle-like; promesonotal groove absent; metanotal groove absent; propodeal spines moderate, relatively wide, with acute apex; humeral area laterally weakly produced (Fig. 24D). Surface shiny with fine rugofoveolae, dorsal and lateral sides of pronotum with additional transverse and thin rugae. Pilosity relatively dense, long, and erect ( Fig. 24D, F). Petiole. Shiny with fine and dense foveolae; node foveolate, low, triangular, with rounded and thin apex, in rear view node dorsoventrally convex; pilosity moderately sparse and erect (Fig. 24D, F). Postpetiole. Shiny, with fine and sparse rugofoveolae; in dorsal view postpetiole oval, lateral margins medially with two dentate projections; pilosity long, moderately sparse, and erect (Fig. 24D, F). Gaster. Shiny and smooth; pilosity moderately dense, long, and erect (Fig. 24D, F). Colour. Ochreous; legs dark yellow, gaster and mandibles brown (Fig. 24D, F). Head. Cephalic margin indistinctly convex (Fig. 24A). Pilosity relatively sparse, long, decumbent to subdecumbent. Head foveolate with additional indistinct longitudinal rugulae on medial frons, area posterolateral from eyes with reduced sculpture; antennal sockets with few thick, curved outward rugae and foveolate interspaces. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, surpassing the posterior head margin by two-fifths of its length; pilosity dense, subdecumbent to erect (Fig. 24A, C). Mesosoma. In lateral view, promesonotum moderately high and long, arched; promesonotal groove present but indistinct; metanotal groove present and distinct; propodeal spines very small, triangular (Fig. 24C). Mesosomal dorsum rugofoveolate; lateral sides of pronotum foveolate, anepisternum and katepisternum smooth, lateral sides of propodeum with smooth notches. Pilosity sparse, moderately long, and erect (Fig. 24C, E). Petiole. Peduncle with ventral face relatively straight (Fig. 24C, E). Gaster. With sparse, erect pilosity ( Fig. 24C, E). Colour. Dark orange (Fig. 24C, E).
Etymology. From the type locality. Biology. The species was collected at 1125 m in elevation, in rainforest. Nest was located in rotten log.
Comments. Pheidole anosyenne sp. nov., described from Anosyenne Mts. in Toliara, has major workers with dense and thick rugae that are anteromedially longitudinal and posteromedially irregular with sparsely and distinctly rugofoveolate interspaces, and ferruginous body colouration. Most similar are P. joffreville sp. nov. and P. mivory sp. nov., known from remote localities in Antsiranana. Major workers of P. anosyenne sp. nov. can be easily separated from both of those taxa based on sparse to moderately sparse, moderately long to long, decumbent to erect pilosity on sides of head, brighter body colouration and presence of smooth notches on lateral sides of pronotum and katepisternum; minor workers differ from P. joffreville sp. nov. in brighter body colouration, presence of smooth notches on lateral sides of propodeum, and entirely smooth anepisternum and katepisternum, from P. mivory sp. nov. in foveolate mesosomal dorsum, brighter body colouration, and less developed propodeal spines.  (CASC).

Pheidole antranohofa
Diagnosis. Moderately large species. Major workers. Head in full-face view suboval, widening posteriorly, with anterior and posterior sides convex, in lateral view suboval; ventral and dorsal faces convex; sides of the head with dense, short, suberect pilosity; anterior and medial parts of frons with moderately dense and thick, longitudinal and sometimes interrupted rugae with distinctly rugofoveolate interspaces; posterolateral sides with longitudinally irregular and thick rugae with distinctly rugofoveolate interspaces, area posterolateral from eyes without smooth notches; scape, when laid back, exceeding the midlength of head by approximately one-fifth of its length; inner hypostomal teeth distinct, moderately long, closely spaced, triangular, with rounded apex and wide base; outer hypostomal teeth lobe-like, wider and higher than inner hypostomal teeth, apex directed outward; inner and outer hypostomal teeth closely spaced and connected by indistinct concavity; promesonotum predominantly rugofoveolate, with additional sparse, thin, transverse rugae on pronotum; propodeum with fine rugofoveolae; gaster smooth; body yellowish orange. Minor workers. Head foveolate with additional indistinct rugulae on frons and vertex, area posterolateral from eyes with reduced sculpture, on posterior part predominantly smooth; scape, when laid back, surpassing the posterior head margin by two-fifths of its length; promesonotum moderately high and short; promesonotal groove present; propodeal spines indistinct, triangular; mesosoma smooth and shiny, only dorsum with few transverse, indistinct rugulae and propodeum with indistinct and sparse foveolae; body dark yellow. Head. In full-face view sub-oval, widening posteriorly, with anterior and posterior sides convex (Fig. 25B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth invisible. Sides of the head with dense, short, suberect pilosity; whole head with relatively dense, short, decumbent to erect pilosity. Anterior and medial parts of frons with moderately dense and thick, longitudinal and sometimes interrupted rugae with distinctly rugofoveolate interspaces; posterolateral sides with longitudinally irregular and thick rugae with distinctly rugofoveolate interspaces. Occipital lobes with thick, sparse, irregular rugae, interspaces smooth or with fine, indistinct rugofoveolae. Gena with sparse and thick, longitudinal rugae and smooth interspaces. Area posterolateral from eyes with thin, longitudinal rugae with distinctly rugofoveolate interspaces. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, wide and shallow; median longitudinal carina absent; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by approximately one-fifth of its length; pilosity decumbent to suberect (Fig. 25B, D). Inner hypostomal teeth distinct, moderate, closely spaced, triangular, with rounded apex and wide base; outer hypostomal teeth lobe-like, wider and higher than inner hypostomal teeth, apex directed outward; inner and outer hypostomal teeth closely spaced and connected by indistinct concavity (Fig. 63G). Mesosoma. In lateral view, promesonotum short, angular, and moderately high, posterior mesonotum moderately steep, mesonotal process indistinct, tubercle-like; promesonotal groove absent; metanotal groove absent; propodeal spines moderate, thin, with acute apex; humeral area laterally weakly produced (Fig. 25D). Surface shiny, promesonotum predominantly rugofoveolate, with additional sparse, thin, transverse rugae on pronotum; propodeum with fine rugofoveolae. Pilosity sparse, moderately long, and erect (Fig. 25D, F). Petiole. Shiny with fine and sparse rugofoveolae; node smooth to indistinctly rugulose, low, triangular, with rounded apex, in rear view node dorsoventrally convex; pilosity moderately sparse and erect (Fig. 25D, F). Postpetiole. Shiny, with fine and sparse rugulae; in dorsal view postpetiole oval, lateral margins medially with two dentate projections; pilosity long, moderately sparse, and erect (Fig. 25D, F). Gaster. Shiny and smooth; pilosity sparse, long, and erect (Fig. 25D, F). Colour. Yellowish orange; mandibles and anterior part of head slightly darker (Fig. 25D, F). Head. Cephalic margin indistinctly convex (Fig. 25A). Pilosity relatively sparse, long, and subdecumbent. Head foveolate with additional indistinct rugulae on frons and vertex, area posterolateral from eyes with reduced sculpture and partially smooth; antennal sockets with few thick, curved outward rugae and foveolate interspaces. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, surpassing the posterior head margin by two-fifths of its length; pilosity dense, subdecumbent to erect (Fig. 25A, C). Mesosoma. In lateral view, promesonotum moderately high, short, arched; promesonotal groove present, distinct; metanotal groove present and distinct; propodeal spines indistinct, triangular, apex acute (Fig. 25C). Sculpture smooth and shiny, only dorsum with few transverse, indistinct rugulae and propodeum with indistinct and sparse foveolae. Pilosity sparse, moderately long, and erect ( Fig. 25C, E). Petiole. Peduncle with ventral face relatively straight; node low, knobbed, and small; with few short, erect setae (Fig. 25C, E). Gaster. With sparse, erect pilosity (Fig. 25C, E). Colour. Dark yellow (Fig. 25C, E).
Etymology. From the type locality. Biology. The species was collected at 1325 m in elevation, in montane rainforest. Nests were located in rotten logs, root mat and rotten tree stump.
Comments. Pheidole antranohofa sp. nov. is known only from its type locality: Parc National de Marojejy in Antsiranana. Morphologically it is most similar to P. sikorae Forel which is widely distributed from Forêt Ambohidena in Toamasina to Andrambovato in Fianarantsoa. Major workers of P. antranohofa sp. nov. can be distinguished based on developed sculpture of mesosoma, absence of impressed and smooth concavity placed lateral to antennal socket and tentorial pit and distinctly rugofoveolate interspaces on frons. However, minors of P. antranohofa sp. nov. and P. sikorae are indistinguishable.  (CASC). Paratype. • 1w.; same data as for holotype, CASENT0923276 (CASC).

Pheidole beanka
Diagnosis. Minute species. Major workers. HL < 0.9 mm and WL < 0.7 mm; head in full-face view elongate, not widening posteriorly with posterior sides slightly convex, in lateral view sub-oval and short with convex dorsal and ventral sides; body ocherous; sides of head with moderately dense, moderately short, suberect to erect pilosity; entire head distinctly sculptured, medial part of frons with thick and longitudinal rugae and distinctly rugulate and never smooth interspaces, occipital lobes with dense and irregular rugae with distinctly rugoreticulate interspaces; scape, when laid back, exceeding the midlength of head by one-fifth of its length; lateral sides of promesonotum distinctly foveolate without additional sparse and indistinct rugulae; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, approximately the same height and width as inner teeth; inner and outer hypostomal teeth closely spaced and not connected by concavity; base of first gastral tergite shagreened. Minor workers. HL < 0.45 mm and WL < 0.5 mm, scape, when laid back, surpassing the posterior head margin by one-fifth of its length; propodeal spines reduced to small tubercles; head relatively rectangular; body yellowish brown; lateral sides of frons smooth; vertex with transverse, sparse, and moderately thick, short rugulae; mesosoma smooth. Head. In full-face view elongate, not widening posteriorly, with anterior and posterior sides slightly convex (Fig. 26B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with moderately dense, moderately short, suberect to erect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with thick, longitudinal, and dense rugae and distinctly rugulate interspaces, rugae more irregular and with denser sculpture of interspaces on posteromedial part; lateral sides with thick, dense and longitudinal rugae with distinctly rugofoveolate interspaces, rugae more irregular on posterolateral parts. Occipital lobes with dense, irregular rugae and distinctly rugoreticulate interspaces. Area posterolateral from eyes with dense rugofoveolae. Gena with relatively sparse and thick, longitudinal rugae and indistinctly rugoreticulate interspaces. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina absent; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by one-fifth of its length; pilosity subdecumbent to erect (Fig. 26B, D). Inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, approximately the same height and width as inner teeth; inner and outer hypostomal teeth closely spaced and not connected by concavity (Fig. 63H). Mesosoma. In lateral view, promesonotum short, angular, and moderately high, posterior mesonotum moderately steep, mesonotal process very indistinct, tubercle-like; promesonotal groove absent; metanotal groove absent; propodeal spines very small, with wide base and acute apex; humeral area produced (Fig. 26D). Surface shiny and distinctly foveolate; katepisternum with sparser foveolae. Pilosity sparse, moderately long, and erect (Fig. 26D, F). Petiole. Shiny with dense foveolae; node finely foveolate, triangular, with rounded and thin apex, in rear view node dorsoventrally concave; pilosity moderately sparse and erect (Fig. 26D, F). Postpetiole. Shiny and foveolate; dorsum with reduced sculpture; in dorsal view oval, lateral margins medially with two distinct dentate projections; pilosity long, moderately sparse, and erect (Fig. 26D, F). Gaster. Shiny and smooth with shagreened base; pilosity moderately dense, moderately short, and erect (Fig. 26D, F). Colour. Ochreous with yellow legs and antenna (Fig. 26D, F). Head. Cephalic margin slightly concave (Fig. 26A). Pilosity relatively sparse, moderately long, decumbent to subdecumbent. Sculpture shiny and smooth; vertex with transverse, sparse, and moderately thick, short rugulae; antennal sockets with few thick, curved outward rugae and smooth interspaces. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, exceeding the posterior head margin by one-fifth of its length; pilosity dense, subdecumbent to erect (Fig. 26A, C). Mesosoma. In lateral view, promesonotum moderately high and short, box-like; promesonotal groove absent; metanotal groove distinct; propodeal spines reduced to small tubercles (Fig. 26C). Sculpture shiny and smooth. Pilosity sparse, moderately long, and erect (Fig. 26C, E). Gaster. With sparse, erect pilosity (Fig. 26C, E). Colour. Yellow (Fig. 26C, E).
Etymology. From the type locality. Biology. The species was collected at 272 m in elevation, in tropical dry forest. Nest was located in rotten log.
Comments. Pheidole beanka sp. nov. belongs to the group of species characterised by small body size (major workers: HL < 1.05 mm, WL < 0.9 mm and minor workers HL < 0.5 mm, WL < 0.6 mm), elongate and not widening posteriorly head in major workers, and minor workers with predominantly smooth and relatively rectangular head and yellow to brown body colouration. The group includes five species: P. flavominuta sp. nov., P. nitidobruna sp. nov., P. mikros sp. nov., and P. beanka sp. nov. Pheidole beanka sp. nov., described from Réserve forestière Beanka, is the only member of this group known from the Mahajanga and its distribution doesn't overlap with the remaining four taxa. However, morphology of P. beanka sp. nov. is most similar to P. mikros sp. nov., which is distributed on the southernmost part of the Antsiranana prefecture. Major workers of Pheidole beanka sp. nov. differ from P. mikros sp. nov. in the combination of the following characters: medial part of frons with distinctly rugulate interspaces and very small propodeal spines; minor workers can be separated based on smooth lateral sides of frons and mesosoma, yellow body, and propodeal spines reduced to small tubercles.  (CASC).

Diagnosis.
Moderately large species. Major workers. Head in full-face view sub-oval, slightly widening posteriorly, with anterior and posterior sides convex, in lateral view sub-oval, ventral and dorsal faces convex; sides of the head with dense, moderately long, erect pilosity; medial part of frons with moderately dense and thick rugae, anteriorly rugae longitudinal and interrupted, posteromedially rugae irregular, interspaces shiny with sparse and indistinct irregular rugulae; lateral sides with irregular, thick, and relatively sparse rugae with indistinctly rugoreticulate interspaces; occipital lobes, and area posterolateral from eyes never smooth; scape, when laid back, exceeding the midlength of head by two-fifths of its length; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, wider than inner hypostomal teeth and approximately the same height, apex directed outward; inner and outer hypostomal teeth closely spaced and connected by indistinct concavity; pronotum and mesonotum with fine rugoreticulae and additional transverse to irregular, thick rugae; anepisternum, katepisternum and propodeum with fine rugoreticulae; body orange. Minor workers. Head foveolate; medial part of frons with smooth notch; vertex and lateral sides of frons with additional, irregular to arcing rugae, area posterolateral from eyes smooth; scape, when laid back, surpassing the posterior head margin by two-fifths of its length; promesonotum moderately low and moderately short; promesonotal groove indistinct; propodeal spines small and triangular; mesosoma with very indistinct and sparse rugofoveolae; dorsal pronotum and medial parts of lateral sides of pronotum, katepisternum, and anepisternum smooth; body yellow.
Description Head. In full-face view sub-oval, slightly widening posteriorly, with anterior and posterior sides convex (Fig. 27B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with dense, moderately long, erect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with moderately dense and thick rugae, anteriorly rugae longitudinal and interrupted, posteromedially rugae irregular, interspaces shiny with sparse and indistinct irregular rugulae; lateral sides with irregular, thick, and relatively sparse rugae with indistinctly rugoreticulate interspaces. Occipital lobes with sparse, thick, and irregular rugae; interspaces smooth. Gena with relatively dense and thick longitudinal rugae and smooth interspaces. Area posterolateral from eyes with thin and dense rugofoveolae, sculpture weakening posteriorly. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina present; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by two-fifths of its length; pilosity subdecumbent to erect (Fig. 27B, D). Inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, wider than inner hypostomal teeth and approximately the same height, apex directed outward; inner and outer hypostomal teeth closely spaced and connected by indistinct concavity (Fig. 63I). Mesosoma. In lateral view, promesonotum short, angular, and moderately low, posterior mesonotum moderately steep, mesonotal process indistinct, tubercle-like; promesonotal groove absent; metanotal groove indistinct; propodeal spines moderately long, moderately wide, with acute apex; humeral area laterally weakly produced (Fig. 27D). Surface shiny; pro-notum and mesonotum with fine rugoreticulae and additional transverse to irregular, thick rugae; anepisternum, katepisternum, and propodeum with fine rugoreticulae. Pilosity relatively dense, long, and erect ( Fig. 27D, F). Petiole. Shiny with fine and dense rugofoveolae; node smooth, low, triangular, with rounded and thin apex, in rear view node dorsoventrally slightly convex; pilosity moderately sparse and erect (Fig. 27D, F). Postpetiole. Shiny and smooth; in dorsal view oval, lateral margins medially with two dentate projections; pilosity long, moderately sparse, and erect ( Fig. 27D, F). Gaster. Shiny and smooth; pilosity moderately dense, long, and erect ( Fig. 27D, F). Colour. Orange; mandibles and gaster slightly darker; legs yellowish ( Fig. 27D, F). Etymology. From the type locality. Biology. The species was collected between 940-1250 m in elevation, in rainforest and montane rainforest. Nests were located in rotten logs and dead twigs above ground.
Comments. Pheidole befotaka sp. nov. is a member of a group of species characterised by body coloration that is bright, yellow to orange in majors and yellow in minors, head sub-oval, not widening posteriorly with sides not convex or convex indistinctly, and medial part of frons with longitudinal and interrupted rugae anteriorly and distinctly irregular rugae posteriorly. The group includes three taxa: P. vony sp. nov., P. befotaka sp. nov., and P. mamiratra sp. nov. Pheidole befotaka sp. nov. is the only member of the group known from Parc National Befotaka-Midongy in Fianarantsoa and can be easily separated based on orange body of major workers with slightly convex lateral sides of head and lateral sides of frons with distinctly irregular rugae. Minor workers of P. befotaka sp. nov. can be separated from P. vony sp. nov. and P. mamiratra sp. nov. based on presence of additional, irregular to arcing rugae on vertex and lateral sides of frons. Additionally, minors of P. befotaka sp. nov. can be confused with minors of sympatric P. veteratrix from which they differ in reduced sculpture of mesosoma and higher promesonotum.  (CASC).
Diagnosis. Moderately large species. Major workers. Head in full-face view sub-oval, not widening posteriorly, with anterior and posterior sides relatively straight, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with moderately dense, moderately long, subdecumbent to suberect pilosity; medial part of frons with thick, interrupted, sparse, and longitudinal rugae with indistinctly foveolate interspaces; anterolateral sides of frons with sparse, thick, and longitudinal rugae, posterolateral sides with rugae more irregular, interspaces with sparse foveolae; occipital lobes, and area posterolateral from eyes without smooth notches; scape, when laid back, exceeding the midlength of head by twofifths of its length; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, narrower, and approximately as high as inner teeth; inner and outer hypostomal teeth closely spaced and not connected by concavity; mesosoma rugofoveolate; dorsal promesonotum with additional thick and transverse rugae; lateral sides of pronotum with smooth notches; gaster smooth; body orange. Minor workers. Head foveolate; vertex and median frons with fading sculpture; area posterolateral from eyes smooth; antennal sockets with few indistinct, curved outward rugae and foveolate interspaces; scape, when laid back, exceeding the posterior head margin by one-third of its length; promesonotum low and moderately long; promesonotal groove absent; propodeal spines small and triangular; mesosoma predominantly smooth; lateral sides with very sparse and indistinct, thin rugulae; body brown.
Description Head. In full-face view sub-oval, not widening posteriorly, with anterior and posterior sides relatively straight (Fig. 28B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with moderately dense, moderately long, subdecumbent to suberect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with thick, interrupted, sparse, and longitudinal rugae with indistinctly foveolate interspaces; anterolateral sides of frons with sparse, thick, and longitudinal rugae, posterolateral sides with rugae more irregular, interspaces with sparse foveolae. Occipital lobes with slightly thinner, sparse, and irregular rugae and smooth to indistinctly foveolate interspaces. Area posterolateral from eyes with denser and thinner longitudinal rugae with rugofoveolate interspaces. Gena with relatively sparse and thick, longitudinal rugae with distinctly rugofoveolate interspaces. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina absent; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by two-fifths of its length; pilosity subdecumbent to erect (Fig. 28B, D). Inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, narrower than and approximately as high as inner teeth; inner and outer hypostomal teeth closely spaced and not connected by concavity (Fig. 63J). Mesosoma. In lateral view, promesonotum short, angular and moderately low, posterior mesonotum moderately steep, mesonotal process indistinct, tubercle-like; promesonotal groove absent; metanotal groove absent; propodeal spines short, with wide base and acute apex; humeral area produced (Fig.  28D). Surface shiny and rugofoveolate; dorsal promesonotum with additional thick and transverse rugae; lateral sides of pronotum with smooth notches. Pilosity moderately dense, long, and erect ( Fig. 28D, F). Petiole. Shiny with dense foveolae; node finely foveolate, triangular, with rounded and thick apex, in rear view node dorsoventrally slightly convex; pilosity moderately sparse and erect (Fig. 28D, F). Postpetiole. Shiny and foveolate; dorsum with reduced sculpture and smooth notch; in dorsal view oval, lateral margins medially with two dentate projections; pilosity long, moderately sparse and erect ( Head. Cephalic margin slightly convex (Fig. 28A). Pilosity relatively sparse, moderately long, subdecumbent to erect. Sculpture shiny and foveolate; vertex and median frons with fading sculpture; area posterolateral from eyes smooth; antennal sockets with few indistinct, curved outward rugae and foveolate interspaces. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, exceeding the posterior head margin by one-third of its length; pilosity dense, subdecumbent to erect (Fig. 28A, C). Mesosoma. In lateral view, promesonotum low and moderately long, arched; promesonotal groove absent; metanotal groove distinct; propodeal spines small, triangular (Fig. 28C). Sculpture shiny and predominantly smooth; lateral sides with very sparse and indistinct, thin rugulae. Pilosity very sparse, moderately long, and erect ( Fig. 28C, E). Gaster. With sparse, erect pilosity ( Fig. 28C, E). Colour. Brown, legs and gaster brighter (Fig. 28C, E). Etymology.
Greek for forest in reference to habitat preferences of the species. Biology. The species was collected between 225-415 m in elevation, in rainforest. Nests were located in rotten logs.
Comments. Pheidole dasos sp. nov., described from Makirovana forest in Antsiranana, is most similar to P. hazo sp. nov., known from the vicinity of Andranoma in Antanana- rivo, and P. sparsa sp. nov., recorded so far only from Bemanevika in Mahajanga. Majors of P. dasos sp. nov. can be distinguished from both taxa by medial part of frons with moderately dense rugae with interspaces with indistinct foveolae, and pronotum predominantly sculptured with smooth notches on lateral sides; minors of P. dasos sp. nov. can be distinguished from P. sparsa sp. nov. and P. hazo sp. nov. by brown body colouration, longer scape exceeding the posterior head margin by one-third of its length, and predominantly smooth mesosoma with very sparse and indistinct, thin rugulae on lateral sides.  (CASC).
Diagnosis. Minute species. Major workers. HL < 0.85 mm and WL < 0.65 mm; head in full-face view elongate, not widening posteriorly with posterior sides slightly convex, in lateral view sub-oval and elongate with slightly convex dorsal and ventral sides; body yellow; sides of head with moderately dense, short, suberect to erect pilosity; entire head distinctly sculptured but with smooth interspaces; scape, when laid back, reaching the midlength of head; inner hypostomal teeth distinct, moderate, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, approximately as high and wide as inner teeth; inner and outer hypostomal teeth moderately closely spaced and not connected by concavity; base of first gastral tergite smooth. Minor workers. HL < 0.45 mm and WL < 0.5 mm, scape, when laid back, reaching the posterior head margin, propodeal spines small and triangular; head relatively rectangular; body yellow; head predominantly smooth; mesosoma smooth. Head. In full-face view elongate, not widening posteriorly, with anterior and posterior sides slightly convex (Fig. 29B). In lateral view sub-oval and elongate; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with moderately dense, short, suberect to erect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with thick, longitudinal, and dense rugae and smooth to indistinctly rugulate interspaces, rugae directed slightly outward on posteromedial part; lateral sides with thick, dense, and irregular rugae, interspaces shiny and distinctly rugoreticulate. Occipital lobes with dense, irregular rugae and distinctly rugoreticulate interspaces. Area posterolateral from eyes with weaker sculpture, rugoreticulate. Gena with relatively sparse and thick longitudinal rugae and smooth interspaces. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina absent; lateral longitudinal carinae absent. Scape, when laid back, reaching the midlength of head; pilosity subdecumbent to erect (Fig. 29B, D). Inner hypostomal teeth distinct, moderate, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, approximately as high and wide as inner teeth; inner and outer hypostomal teeth moderately closely spaced and not connected by concavity (Fig.  63K). Mesosoma. In lateral view, promesonotum short, angular, and moderately low, posterior mesonotum steep, mesonotal process very indistinct, bulge-like; promesonotal groove absent; metanotal groove absent; propodeal spines moderately long, with wide base and acute apex; humeral area laterally weakly produced (Fig. 29D). Surface shiny; promesonotum predominantly smooth with very fine network of rugoreticulae; anepisternum, katepisternum, and propodeum with rugoreticulae denser and thicker. Pilosity moderately dense, moderately long, and erect ( Fig. 29D, F). Petiole. Shiny with dense foveolae; node smooth to finely foveolate, triangular, with rounded and thick apex, in rear view node dorsoventrally convex; pilosity moderately sparse and erect (Fig. 29D, F). Postpetiole. Shiny and foveolate; dorsum with reduced sculpture and smooth notch; in dorsal view oval, lateral margins medially with two dentate projections; pilosity long, moderately sparse, and erect ( Fig. 29D, F). Gaster. Shiny and smooth; pilosity moderately dense, moderately short, and erect ( Head. Cephalic margin indistinctly concave to straight (Fig. 29A). Pilosity relatively dense, moderately long, decumbent to suberect. Sculpture shiny and smooth; lateral sides of frons with fine, sparse, longitudinal, and interrupted rugulae; vertex with indistinct, sparse, and transverse rugulae; antennal sockets with few thick, curved outward rugae and smooth interspaces. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, reaching the posterior head margin; pilosity dense, subdecumbent to erect (Fig. 29A, C). Mesosoma. In lateral view, promesonotum moderately high and short, arched; promesonotal groove absent; metanotal groove distinct; propodeal spines small and triangular (Fig. 29C). Sculpture shiny and smooth. Pilosity moderately sparse, moderately long, and erect  Etymology. Latin for bright and small in reference to small body size and bright colouration.
Biology. The species was collected between 355-520 m in elevation, in rainforest. Nests were located in rotten logs, and under rootmats on the ground.
Comments. Pheidole flavominuta sp. nov. belongs to the group of species characterised by small body size (major workers: HL < 1.05 mm, WL < 0.9 mm and minor workers HL < 0.5 mm, WL < 0.6 mm), head in major workers elongate and not widening posteriorly, minor workers with predominantly smooth and relatively rectangular head, and yellow to brown body colouration. The group includes four species: P. flavominuta sp. nov., P. nitidobruna sp. nov., P. mikros sp. nov., and P. beanka sp. nov. Distribution of P. flavominuta sp. nov. covers area north from Toamasina up to Antenina and doesn't overlap with other members of this group. Pheidole flavominuta sp. nov. strongly differs from other members of the group by having distinctly yellow body colouration in major and minor workers. Additionally, major workers have head, in lateral view, sub-oval and elongate with slightly convex dorsal and ventral sides, and first gastral tergite is entirely smooth. Minor workers of this species can be also separated by a short antennal scape which doesn't exceed the posterior head margin.  (CASC).
Diagnosis. Moderately large species. Major workers. Head in full-face view suboval and not widening posteriorly, with anterior and posterior sides slightly convex, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with dense, short, decumbent to suberect pilosity; medial part of frons with moderately thick, longitudinal, interrupted, and moderately dense rugae, interspaces rugulate, rugae directed slightly outward on posteromedial part; occipital lobes predominantly smooth, only anterior part with indistinct, dense, thin, and longitudinal rugae; area posterolateral from eyes with indistinct, dense, thin, and longitudinal rugae, posteriormost part smooth; scape, when laid back, exceeding the midlength of head by approximately two-fifths of its length; inner hypostomal teeth distinct, low, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth dentate, wider and higher then inner teeth; inner and outer hypostomal teeth closely spaced and connected by indistinct concavity; mesosoma distinctly foveolate; promesonotum with additional sparse and moderately thick, irregular to transverse rugae on dorsum; katepisternum with smooth notch; body yellowish orange. Minor workers. Head foveolate; vertex with additional, short, and transverse rugulae; area posterolateral from eyes with weaker sculpture that appears smooth; scape, when laid back, exceeding the posterior head margin by two-fifths of its length; promesonotum low and moderately long; prome-sonotal groove present; propodeal spines moderately large with narrow base; mesosoma foveolate; katepisternum with smooth notch; body yellow to orange.
Etymology. Latin for slender in reference to body sculpture. Biology. The species was collected at 1300 m in elevation, in montane rainforest. Nests were located in dead branches above ground.
Comments. Pheidole gracilis sp. nov. is a member of a group of species characterised by distinctly reduced head sculpture in major workers with occipital lobes entirely or predominantly smooth, area posterolateral from eyes partially or entirely smooth and shiny or with reduced sculpture and smooth notches. The group consists of four species: P. litigiosa, P. masoandro sp. nov., P. gracilis sp. nov., and P. tampony sp. nov. Pheidole gracilis sp. nov. is known only from Parc National Montagne d'Ambre in Antsiranana and its distribution doesn't overlap with other members of this group. Morphologically the species is most similar to P. litigiosa, known from the vicinity of Antananarivo, and P. masoandro sp. nov., described from Anosyenne Mts. in Toliara. Its major workers can be easily separated from both of those taxa based on more developed head sculpture with occipital lobes anteriorly covered by indistinct, dense, thin, and longitudinal rugae and distinctly foveolate promesonotum; minor workers can be separated based on foveolate mesosoma and low and long promesonotum. Minor workers of P. gracilis sp. nov. are similar to minors of P. tampony sp. nov. and P. befotaka sp. nov. but can be separated based on more developed head sculpture with additional, short, and transverse rugulae on vertex and area posterolateral from eyes with weak but distinct sculpture and lacking smooth notches.  (CASC).
Diagnosis. Moderately large species. Major workers. Head in full-face view suboval, not widening posteriorly, with anterior and posterior sides relatively straight, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with dense, moderately long, suberect to erect pilosity; medial part of frons with thick, longitudinal, and dense rugae, interspaces predominantly smooth to indistinctly rugulate, rugae more irregular and directed slightly outward on posteromedial part; lateral sides with thick, dense, and longitudinal rugae with sparsely rugulate interspaces, rugae more irregular on posterolateral parts; occipital lobes without smooth notches; area posterolateral from eyes with sculpture weakening posteriorly and smooth notches; scape, when laid back, exceeding the midlength of head by two-fifths of its length; inner hypostomal teeth distinct, small, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, wider than inner teeth, and approximately the same height; inner and outer hypostomal teeth closely spaced and not connected by concavity; mesosoma foveolate; promesonotum with additional thin, moderately sparse, transverse to irregular rugae; katepisternum with smooth notch; gaster smooth; body orange. Minor workers. Head smooth; lateral sides of frons with longitudinal, short, and thick rugae; vertex with very short, sparse, and transverse to arcing rugae; scape, when laid back, exceeding the posterior head margin by two-fifths of its length; promesonotum moderately low and short, arched; promesonotal groove absent; propodeal spines very small, triangular; mesosoma smooth; dorsal promesonotum with very sparse and irregular rugae; propodeum with sparse, irregular, and indistinct rugulae; body yellow.
Description Head. In full-face view elongate, not widening posteriorly, with anterior and posterior sides relatively straight (Fig. 31B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with dense, moderately long, suberect to erect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with thick, longitudinal, and dense rugae, interspaces predominantly smooth to indistinctly rugulate, rugae more irregular and directed slightly outward on posteromedial part; lateral sides with thick, dense, and longitudinal rugae with sparsely rugulate interspaces, rugae more irregular on posterolateral parts. Occipital lobes with dense, irregular rugae and sparsely rugulate interspaces. Area posterolateral from eyes with weaker and more irregular sculpture, sculpture weakening posteriorly and smooth on the posteriormost part. Gena with relatively sparse and thick longitudinal rugae and distinctly rugulate interspaces. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina absent; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by two-fifths of its length; pilosity subdecumbent to erect (Fig. 31B, D). Inner hypostomal teeth distinct, small, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, wider than inner teeth and approximately the same height; inner and outer hypostomal teeth closely spaced and not connected by concavity (Fig. 63M). Mesosoma. In lateral view, promesonotum short, angular, and moderately low, posterior mesonotum moderately steep, mesonotal process indistinct, tubercle-like; promesonotal groove absent; metanotal groove indistinct; propodeal spines short, with wide base and acute apex; humeral area weakly produced (Fig. 31D). Surface shiny and foveolate; promesonotum with additional thin, moderately sparse, transverse to irregular rugae; katepisternum with smooth notch. Pilosity dense, long, and erect (Fig. 31D, F). Petiole. Shiny with sparse foveolae; node finely foveolate, triangular, with rounded and thick apex, in rear view node dorsoventrally convex; pilosity moderately sparse and erect (Fig. 31D, F). Postpetiole. Shiny and foveolate; dorsum smooth; in dorsal view oval, lateral margins medially with two dentate projections; pilosity long, moderately sparse, and erect (Fig. 31D, F). Gaster. Shiny and smooth; pilosity very dense, moderately long, and erect (Fig. 31D, F). Colour. Orange with yellow legs (Fig. 31D, F). Head. Cephalic margin slightly concave (Fig. 31A). Pilosity relatively dense, moderately long, decumbent to subdecumbent. Sculpture shiny and smooth; lateral sides of frons with longitudinal, short and thick rugae; vertex with very short, sparse, and transverse to arcing rugae; antennal sockets with few thick, curved outward rugae and smooth interspaces. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, exceeding the posterior head margin by two-fifths of its length; pilosity dense, suberect to erect (Fig. 31A, C). Mesosoma. In lateral view, promesonotum moderately low and short, arched; promesonotal groove absent; metanotal groove distinct; propodeal spines very small, triangular (Fig. 31C). Sculpture shiny and smooth; dorsal promesonotum with very sparse and irregular rugae; propodeum with sparse, irregular, and indistinct rugulae. Pilosity sparse, moderately long, and erect (Fig. 31C, E). Gaster. With moderately dense, erect pilosity (Fig.  31C, E). Colour. Yellow (Fig. 31C, E). Etymology. Malagasy for orange in reference to body colouration. Biology. The species was collected at 1550 m in elevation, in montane rainforest. Nests were located in rotten logs and under stones.
Comments. Pheidole haboka sp. nov., described from Forêt d'Atsirakambiaty in Fianarantsoa, is most similar to P. sparsa sp. nov. and P. dasos sp. nov., both known from the northern part of the island, and P. hazo sp. nov., recorded so far only from the vicinity of Andranoma in Antananarivo. Majors of P. haboka sp. nov. can be easily distinguished from all taxa mentioned above by area posterolateral from eyes with sculpture weakening posteriorly and smooth notches and very dense pilosity on gaster; minors can be separated based on body sculpture predominantly smooth and lacking foveolae.  (CASC).
Diagnosis. Minute species. Major workers. HL < 1.1 mm and WL < 0.9 mm; head, in full-face view, sub-oval, slightly widening posteriorly, with anterior and posterior sides convex, in lateral view sub-oval; ventral and dorsal faces convex; body dark orange; sides of head with moderately dense, moderately long, subdecumbent to suberect pilosity; entire head distinctly sculptured, medial part of frons with longitudinal rugae, rugae in posteromedial part more irregular, interspaces shiny with dense, distinct, and irregular rugulae; scape, when laid back, slightly exceeding the midlength of head; mesosoma predominantly rugofoveolate, pronotal dorsum and lateral sides of propodeum with reduced sculpture; inner hypostomal teeth distinct, moderately high, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, wider and higher than inner hypostomal teeth, apex directed outward; inner and outer hypostomal teeth closely spaced, connected by indistinct concavity; base of first gastral tergite smooth. Minor workers. HL < 0.5 mm and WL < 0.6 mm, scape, when laid back, surpassing the posterior head margin by one-fifth of its length; propodeal spines very small, triangular; head relatively rectangular; body yellow; head foveolate, frons with additional indistinct longitudinal and interrupted rugae in medial part, area posterolateral from eyes smooth; mesosoma smooth. Head. In full-face view sub-oval, slightly widening posteriorly, with anterior and posterior sides convex (Fig. 32B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with moderately dense, moderately long, subdecumbent to suberect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with moderately dense, thick, longitudinal rugae, rugae in posteromedial part more irregular and directed outward, interspaces shiny with dense and distinct irregular rugulae; lateral sides with longitudinal to irregular and thick rugae with distinctly rugofoveolate interspaces. Occipital lobes with sparse, thick, and irregular rugae; interspaces smooth to indistinctly rugulate. Gena with relatively dense and thick longitudinal rugae and distinctly rugofoveolate interspaces. Area posterolateral from eyes with dense and thick rugofoveolae. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina present; lateral longitudinal carinae absent. Scape, when laid back, slightly exceeding the midlength of head; pilosity decumbent to erect (Fig. 32B, D). Inner hypostomal teeth distinct, moderately high, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, wider and higher than inner hypostomal teeth, apex directed outward; inner and outer hypostomal teeth closely spaced, connected by indistinct concavity (Fig. 63N). Mesosoma. In lateral view, promesonotum short, angular, and moderately high, posterior mesonotum moderately steep, mesonotal process indistinct, tubercle-like; promesonotal groove absent; metanotal groove absent; propodeal spines moderately long, moderately wide, with acute apex; humeral area laterally weakly produced (Fig. 32D). Surface shiny and predominantly rugofoveolate, pronotal dorsum and lateral sides of propodeum with reduced sculpture. Pilosity relatively dense, long, and erect ( Fig. 32D, F). Petiole. Shiny with fine and dense rugofoveolae; node partially smooth, low, triangular, with rounded and thin apex, in rear view node dorsoventrally slightly concave; pilosity moderately sparse and erect (Fig. 32D, F). Postpetiole. Shiny and smooth; in dorsal view oval, lateral margins medially with two dentate projections; pilosity long, moderately sparse, and erect (Fig. 32D, F). Gaster. Shiny and smooth; pilosity moderately dense, long, and erect (Fig. 32D, F). Colour. Dark orange; legs yellow ( Fig. 32D, F). Head. Cephalic margin indistinctly concave or straight (Fig. 32A). Pilosity relatively sparse, long, decumbent to subdecumbent. Sculpture foveolate; frons with addi- tional indistinct longitudinal and interrupted rugae in medial part; area posterolateral from eyes smooth. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, surpassing the posterior head margin by one-fifth of its length; pilosity dense, subdecumbent to erect (Fig. 32A, C). Mesosoma. In lateral view, promesonotum moderately low and short, arched; promesonotal groove absent; metanotal groove present and distinct; propodeal spines very small and triangular (Fig. 32C). Sculpture smooth. Pilosity very sparse, moderately long, and erect ( Fig. 32C, E). Postpetiole. Short, low, and relatively flat; with few short, erect setae (Fig. 32C, E). Gaster. With sparse, erect pilosity (Fig. 32C, E). Colour. Yellow, vertex slightly darker (Fig. 32C, E).
Etymology. Malagasy for hill or mountain in reference to type locality. Biology. The species was collected at 1125 m in elevation, in rainforest. Nests were located in rotten logs under stone and in root mats.
Comments. Pheidole havoana sp. nov. belongs to the group of species characterised by small body size (major workers: HL < 1.05 mm, WL < 0.9 mm and minor workers HL < 0.5 mm, WL < 0.6 mm), head sub-oval, slightly widening posteriorly with anterior and posterior sides convex in major workers, and minor workers with yellow to brown body colouration and head foveolate or predominantly smooth and relatively oval. The group includes six species: P. havoana sp. nov., P. kely sp. nov., P. parvula sp. nov., P. parvulogibba sp. nov., P. volontany sp. nov., and P. midongy sp. nov. Within this group, P. havoana sp. nov., described form Anosyenne Mts. in Toliara, is most similar to P. kely sp. nov., distributed in the northern part of the island, P. parvula sp. nov., known from two localities in the vicinity of Antananarivo, and sympatric P. parvulogibba sp. nov. Minor workers of P. havoana sp. nov. distinctly differ from those of P. parvula sp. nov. and P. parvulogibba sp. nov. by predominantly foveolate head and presence of additional indistinct longitudinal and interrupted rugae in medial part of frons. Minor workers of P. havoana sp. nov. and P. kely sp. nov. are indistinguishable. Major workers of P. havoana sp. nov. differ from P. kely sp. nov. and P. parvulogibba sp. nov. by medial part of frons with longitudinal rugae, rugae in posteromedial part more irregular, with densely and distinctly irregular rugulae in interspaces; and from P. parvula sp. nov. in reduced sculpture on pronotal dorsum and lateral sides of propodeum.  (CASC). Paratypes. • 5w., 8s.; same data as for holotype; CASENT0427762, CASENT00872251, CASENT0413711, CASENT0413712, CASENT0427765 (CASC, MHNG, PBZT).
Diagnosis. Moderately large species. Major workers. Head in full-face view suboval, not widening posteriorly, with anterior and posterior sides relatively straight, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with dense, long, suberect to erect pilosity; medial part of frons with moderately dense, thin, longitudinal rugae, rugae in posteromedial portion directed slightly outward, interspaces shiny with sparse and distinct rugofoveolae; lateral sides with longitudinal, thicker, and relatively sparser rugae; interspaces shiny with relatively dense and distinct rugo-foveolae; occipital lobes, and area posterolateral from eyes without smooth notches; scape, when laid back, exceeding the midlength of head by two-fifths of its length; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed slightly outward; outer hypostomal teeth lobe-like, wider than inner hypostomal teeth and approximately the same height, apex directed outward; inner and outer hypostomal teeth closely spaced and connected by concavity; mesosoma with thick and sparse foveolae; pronotum with additional transverse to irregular, thin rugae; katepisternum with smooth notch; gaster smooth; body orange. Minor workers. Head foveolate with additional longitudinal to irregular, interrupted, and moderately thick rugae; area posterolateral from eyes with weaker foveolae and smooth notches; scape, when laid back, surpassing the posterior head margin by one-fifth of its length; promesonotum moderately low and moderately long, arched; promesonotal groove absent; propodeal spines minute and triangular; mesosoma with thick foveolae; lateral sides of propodeum, katepisternum, and anepisternum with smooth notches; body yellow.
Description Head. In full-face view sub-oval, not widening posteriorly, with anterior and posterior sides relatively straight (Fig. 33B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with dense, long, suberect to erect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with moderately dense, thin, longitudinal rugae, rugae in posteromedial directed slightly outward, interspaces shiny with sparse and distinct rugofoveolae; lateral sides with longitudinal, thicker, and relatively sparser rugae; interspaces shiny with relatively dense and distinct rugofoveolae. Occipital lobes with sparse, thick, and longitudinal to irregular rugae; interspaces rugofoveolate. Gena with relatively dense and thick, longitudinal rugae and rugofoveolate interspaces. Area posterolateral from eyes shiny, with dense, longitudinal rugofoveolae. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina absent; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by two-fifths of its length; pilosity subdecumbent to erect (Fig. 33B, D). Inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed slightly outward; outer hypostomal teeth lobe-like, wider than inner hypostomal teeth and approximately the same height, apex directed outward; inner and outer hypostomal teeth closely spaced and connected by concavity (Fig. 63O). Mesosoma. In lateral view, promesonotum short, angular, and moderately low, posterior mesonotum moderately steep, mesonotal process indistinct, tuberclelike; promesonotal groove absent; metanotal groove absent; propodeal spines moderately long, moderately narrow, with acute apex; humeral area laterally weakly produced (Fig. 33D). Surface shiny with thick and sparse foveolae; pronotum with additional transverse to irregular, thin rugae; katepisternum with smooth notch. Pilosity sparse, long, and erect (Fig. 33D, F). Petiole. Shiny with fine and sparse foveolae; node smooth to finely foveolate, low, triangular, with rounded and thin apex, in rear view node dorsoventrally straight to slightly convex; pilosity moderately sparse and erect (Fig. 33D, F). Postpetiole. Shiny and smooth; in dorsal view oval, lateral margins medially with two dentate projections; pilosity long, moderately sparse, and erect (Fig. 33D, F). Gaster.
Etymology. Malagasy for tree in reference to arboreal nesting preferences of the species.
Biology. The species was collected at 1300 m in elevation, in montane rainforest. Nest was located in dead branch above ground.
Comments. Pheidole hazo sp. nov., described from the vicinity of Andranoma in Antananarivo, is most similar to P. dasos sp. nov., known from Makirovana forest in Antsiranana, and P. sparsa sp. nov., recorded so far only from Bemanevika in Mahajanga. Majors of P. hazo sp. nov. can be distinguished from both taxa by medial part of frons with moderately dense rugae with interspaces with distinct rugofoveolae, and pronotum lacking smooth notches; minors of P. hazo sp. nov. can be distinguished from P. sparsa sp. nov. by yellow body colouration, and mesosoma predominantly with dense foveolae, and from P. dasos sp. nov. by yellow body colouration, shorter scape surpassing the posterior head margin by one-fifth of its length, and pronotum with distinct and dense foveolae.  (CASC).
Diagnosis. Moderately large species. Major workers. Head in full-face view suboval, widening posteriorly, with anterior and posterior sides convex, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with moderately dense, moderately long, suberect to erect pilosity; medial part of frons with thick, dense, longitudinal, and interrupted rugae and smooth interspaces, posteromedial frons with more irregular rugae directed slightly outward; lateral sides with thick and dense rugae, interspaces shiny and smooth or indistinctly rugulate; rugae longitudinal on anterolateral sides and more irregular on posterolateral sides; area posterolateral from eyes without smooth notches; scape, when laid back, exceeding the midlength of head by one-fifth of its length; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, wider than inner teeth and approximately the same height; inner and outer hypostomal teeth closely spaced and connected by indistinct concavity; mesosoma with fine rugofoveolae; pronotum with rugofoveolae sparser and additional thin and transverse rugae; gaster smooth; body brown. Minor workers. Head smooth; posterolateral sides of frons with sparse and indistinct foveolae; scape, when laid back, surpassing the posterior head margin by two-fifths of its length; promesonotum moderately high and short, arched; promesonotal groove absent; propodeal spines minute and triangular; mesosoma smooth and shiny; body yellowish brown. Head. In full-face view sub-oval, widening posteriorly, with anterior and posterior sides convex (Fig. 34B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with moderately dense, moderately long, suberect to erect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with thick, dense, longitudinal, and interrupted rugae and smooth interspaces, posteromedial frons with rugae more irregular and directed slightly outward; lateral sides with thick and dense rugae, interspaces shiny and smooth or indistinctly rugulate; rugae longitudinal on anterolateral sides and more irregular on posterolateral sides. Occipital lobes with thinner, irregular rugae and smooth to indistinctly rugoreticulate interspaces. Area posterolateral from eyes with irregular to longitudinal, relatively thick to thin rugulae and rugoreticulate interspaces. Gena with relatively dense, thick, longitudinal rugae and smooth to indistinctly rugoreticulate interspaces. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina present; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by one-fifth of its length; pilosity subdecumbent to erect (Fig. 34B, D). Inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, wider than inner teeth and approximately the same height; inner and outer hypostomal teeth closely spaced and connected by indistinct concavity (Fig. 63P). Mesosoma. In lateral view, promesonotum short, angular, and moderately low, posterior mesonotum moderately steep, mesonotal process very indistinct, tubercle-like; promesonotal groove absent; metanotal groove absent; propodeal spines moderately long, with moderately narrow base and acute apex; humeral area laterally weakly produced (Fig. 34D). Surface shiny with fine rugofoveolae; pronotum with rugofoveolae sparser and additional thin and transverse rugae. Pilosity moderately sparse, long, and erect (Fig. 34D, F). Petiole. Shiny with fine foveolae; node smooth to finely foveolate, triangular, with rounded and thick apex, in rear view node dorsoventrally straight to slightly convex; pilosity moderately sparse and erect (Fig. 34D, F). Postpetiole. Shiny and foveolate; dorsum with reduced sculpture and smooth notch; in dorsal view oval, lateral margins medially with two dentate projections; pilosity long, moderately sparse, and erect ( Head. Cephalic margin indistinctly convex (Fig. 34A). Pilosity relatively sparse, long, decumbent to suberect. Sculpture shiny and smooth; posterolateral sides of frons with sparse and indistinct foveolae; antennal sockets with few thick, curved outward rugae and smooth interspaces. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, surpassing the posterior head margin by two-fifths of its length; pilosity dense, subdecumbent to erect (Fig. 34A,  C). Mesosoma. In lateral view, promesonotum moderately high and short, arched; promesonotal groove absent; metanotal groove distinct; propodeal spines minute and  (Fig. 34C). Sculpture shiny and smooth. Pilosity moderately sparse, long, and erect (Fig. 34C, E). Gaster. With sparse, erect pilosity (Fig. 34C, E). Colour. Yellowish brown (Fig. 34C, E).
Etymology. From the type locality. Biology. The species was collected between 1410-1620 m in elevation, in montane forest and montane rainforest. Nests were located in rotten logs and root mats.
Etymology. From the type locality.
Biology. The species was collected at 925 m in elevation, in montane rainforest. Nest was located in rotten log.
Comments. Pheidole joffreville sp. nov., described from Parc National Montagne d'Ambre in Antsiranana, has major workers with dense and thick rugae, anteromedially longitudinal and posteromedially irregular, with distinctly rugofoveolate interspaces, and brown body colouration. Morphologically is most similar to allopatric P. mivory sp. nov., known from Parc National de Marojejy in Antsiranana. Majors of both taxa are extremely similar and species separation should be supported or based exclusively on minors. Majors of P. joffreville sp. nov. differ from P. mivory sp. nov. in distinctly rugofoveolate interspaces on frons and lack of longitudinal rugae on lateral sides of frons and lack of shagreened sculpture on first gastral tergite; minor workers differ in distinctly foveolate mesosoma with only katepisternum with smooth notch.  (CASC).
Diagnosis. Minute species. Major workers. HL < 1.0 mm and WL < 0.8 mm; head in full-face view sub-oval, widening slightly posteriorly, with anterior and posterior sides convex, in lateral view sub-oval; ventral and dorsal faces convex; body yellowish orange; sides of head with moderately dense, moderately long, suberect to erect pilosity; entire head distinctly sculptured, medial part of frons with thick, dense, longitudinal, and interrupted rugae and smooth to indistinctly rugulate interspaces; scape, when laid back, slightly exceeding the midlength of head; mesosoma with fine and sparse rugofoveolae, pronotum with rugofoveolae reduced and smooth notches on medial parts of dorsum and lateral sides; katepisternum with smooth notch; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, lower than inner teeth and approximately the same weight; inner and outer hypostomal teeth moderately closely spaced and not connected by concavity; base of first gastral tergite smooth. Minor workers. HL < 0.5 mm and WL < 0.6 mm, scape, when laid back, surpassing the posterior head margin by one-fifth of its length; propodeal spines small and triangular; head relatively rectangular; body dark yellow; head foveolate; medial side of frons with sparse, fine, and interrupted rugulae; area posterolateral from eyes smooth; mesosoma smooth. Head. In full-face view sub-oval, widening slightly posteriorly, with anterior and posterior sides convex (Fig. 36B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with moderately dense, moderately long, suberect to erect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with thick, dense, longitudinal, and interrupted rugae and smooth to indistinctly rugulate interspaces; lateral sides with thick, dense, and irregular rugae, interspaces shiny and distinctly rugofoveolate; rugae more longitudinal on anterolateral sides. Occipital lobes with thinner, irregular rugae and smooth to indistinctly rugofoveolate interspaces. Area posterolateral from eyes with sculpture weaker and rugoreticulate; sculpture weakening posteriorly. Gena with relatively sparse, thick, longitudinal rugae and smooth to indistinctly rugoreticulate interspaces. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina present; lateral longitudinal carinae absent. Scape, when laid back, slightly exceeding the midlength of head; pilosity subdecumbent to erect (Fig. 36B, D). Inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, lower than inner teeth and approximately the same weight; inner and outer hypostomal teeth moderately closely spaced and not connected by concavity (Fig. 63R). Mesosoma. In lateral view, promesonotum short, angular, and moderately low, posterior mesonotum moderately steep, mesonotal process very indistinct, tubercle-like or absent; promesonotal groove absent; metanotal groove absent; propodeal spines moderately long, with moderately wide base and acute apex; humeral area laterally weakly produced (Fig.  36D). Surface shiny with fine and sparse rugofoveolae; pronotum with rugofoveolae reduced and smooth notches on medial parts of dorsum and lateral sides; katepisternum with smooth notch. Pilosity moderately sparse, long, and erect (Fig. 36D, F). Petiole. Shiny with fine foveolae; node smooth to finely foveolate, triangular, with rounded and thick apex, in rear view node dorsoventrally straight to slightly convex; pilosity moderately sparse and erect (Fig. 36D, F). Postpetiole. Shiny and foveolate; dorsum with reduced sculpture and smooth notch; in dorsal view oval, lateral margins medially with two dentate projections; pilosity long, moderately sparse, and erect (Fig. 36D, F). Gaster. Shiny and smooth; pilosity dense, moderately long, and erect (Fig. 36D, F). Colour. Yellowish orange; mandibles and gaster brown (Fig. 36D, F). Head. Cephalic margin indistinctly concave to straight (Fig. 36A). Pilosity relatively dense, moderately long, decumbent to suberect. Sculpture shiny and foveolate; medial side of frons with sparse, fine, and interrupted rugulae; area posterolateral from eyes smooth; antennal sockets with few thick, curved outward rugae and indistinctly foveolate interspaces. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, surpassing the posterior head margin by one-fifth of its length; pilosity dense, subdecumbent to erect (Fig. 36A, C). Mesosoma. In lateral view, promesonotum moderately high and short, arched; promesonotal groove absent; metanotal groove distinct; propodeal spines small and triangular (Fig.  36C). Sculpture shiny and smooth. Pilosity moderately sparse, moderately long, and erect (Fig. 36C, E). Gaster. With sparse, erect pilosity (Fig. 36C, E). Colour. Dark yellow, gaster and vertex brown (Fig. 36C, E).
Etymology. Malagasy for small in reference to body size.
Biology. The species was collected between 325-990 m in elevation, in rainforest and Uapaca woodland. Nests were located in rotten logs, under rootmats, and under stones.
Comments. Pheidole kely sp. nov. belongs to the group of species characterised by small body size (major workers: HL < 1.05 mm, WL < 0.9 mm and minor workers HL < 0.5 mm, WL < 0.6 mm), sub-oval, slightly widening posteriorly head with anterior and posterior sides convex in major workers, and minor workers with yellow to brown body colouration and foveolate head or head predominantly smooth and relatively oval. The group includes six species: P. havoana sp. nov., P. kely sp. nov., P. parvula sp. nov., P. parvulogibba sp. nov., P. volontany sp. nov., and P. midongy sp. nov. Pheidole kely sp. nov. is distributed from Toamasina north to Sambava and has a single record from Parc National d'Isalo in Fianarantsoa. Morphologically it is most similar to P. havoana sp. nov. and P. parvulogibba sp. nov., described from the Anosyenne Mts. in Toliara, and parapatric P. parvula sp. nov., known from two localities in the vicinity of Antananarivo. Minor workers of P. kely sp. nov. distinctly differ from those of P. parvula sp. nov. and P. parvulogibba sp. nov. in having a predominantly foveolate head. Minor workers of P. havoana sp. nov. and P. kely sp. nov. are indistinguishable. Major workers of P. kely sp. nov. differ from P. havoana sp. nov. and P. parvula sp. nov. in medial part of frons with thick, dense, longitudinal, and interrupted rugae and smooth to indistinctly rugulate interspaces; from P. parvulogibba sp. nov. in mesosoma with fine and sparse rugofoveolae, pronotum with rugofoveolae reduced, and smooth notches on medial parts of dorsum and its lateral sides.  (CASC). Paratype. •1w.; same data as for holotype, CASENT0923282 (CASC).
Diagnosis. Minute species. Major workers. HL < 0.95 mm and WL < 0.8 mm; head in full-face view sub-oval; body dark brown; sides of head with very dense, short, suberect pilosity; entire head distinctly sculptured; scape, when laid back, exceeding the midlength of head by two-fifths of its length; inner hypostomal teeth distinct, large, with rounded apex; outer hypostomal teeth dentate with apex directed indistinctly outward; inner and outer hypostomal teeth not closely spaced and not connected by concavity. Minor workers. HL < 0.5 mm and WL < 0.6 mm, scape, when laid back, surpassing the posterior head margin by two-fifths of its length, propodeal spines reduced to small lobes, head elongate, and oval and body yellowish brown; head sculpture shiny and predominantly smooth, frons with sparse, short, and longitudinal rugulae; mesosoma shiny and smooth. Head. In full-face view sub-oval, slightly widening posteriorly, with anterior and posterior sides convex (Fig. 37B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with very dense, short, suberect to erect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with thick, dense, longitudinal and interrupted rugae and smooth interspaces, posteromedial frons with rugae more irregular and directed slightly outward; lateral sides with thick, dense, and irregular rugae, interspaces shiny and smooth or indistinctly rugulate. Occipital lobes with thick, irregular rugae and smooth to rugoreticulate interspaces. Area posterolateral from eyes rugoreticulate to rugofoveolate with additional longitudinal thick rugae. Gena with relatively dense, thick, and longitudinal rugae and smooth to indistinctly rugoreticulate interspaces. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina present; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by three-fifths of its length; pilosity subdecumbent to erect (Fig. 37B, D). Inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth dentate and lower than inner teeth with sharp apex directed slightly outward; inner and outer hypostomal teeth not closely spaced and not connected by concavity (Fig. 63S). Mesosoma. In lateral view, promesonotum short, angular, and moderately low, posterior mesonotum moderately steep, mesonotal process very indistinct, tubercle-like; promesonotal groove absent; metanotal groove absent; propodeal spines moderately short, with moderately wide base and acute apex; humeral area laterally weakly produced (Fig. 37D). Surface shiny with fine rugofoveolae; medial parts of lateral sides of pronotum with reduced sculpture. Pilosity moderately dense, long, and erect (Fig. 37D, F). Petiole. Shiny with fine foveolae; node smooth to finely foveolate, triangular, with rounded and thick apex, in rear view node dorsoventrally straight to slightly convex; pilosity moderately sparse and erect (Fig. 37D, F). Postpetiole. Shiny and foveolate; dorsum with reduced sculpture and smooth notch; in dorsal view oval, lateral margins medially with two dentate projections; pilosity long, moderately sparse, and erect (Fig.  37D, F). Gaster. Shiny and smooth; pilosity dense, long, and erect (Fig. 37D, F). Colour. Dark brown; legs, gaster and antennae yellowish brown (Fig. 37D, F). Head. Cephalic margin indistinctly convex (Fig. 37A). Pilosity relatively dense, long, decumbent to suberect. Sculpture shiny and smooth; frons with sparse, short, and longitudinal rugulae; antennal sockets with few thick, curved outward rugae and smooth interspaces. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, surpassing the posterior head margin by two-fifths of its length; pilosity dense, subdecumbent to erect (Fig. 37A, C). Mesosoma. In lateral view, promesonotum moderately high and short, arched; promesonotal groove absent; metanotal groove distinct; propodeal spines reduced to small lobes (Fig. 37C). Sculpture shiny and smooth. Pilosity moderately sparse, long, and erect (Fig. 37C, E). Gaster. With sparse, erect pilosity (Fig. 37C, E). Colour. Yellowish brown (Fig. 37C, E).
Etymology. From the type locality.
Biology. The species was collected at 450 m in elevation, in rainforest. Nest was located in a rotten log.
Comments. Pheidole lavasoa sp. nov., described from Grand Lavasoa, Toliara, resembles the parapatric species P. andohahela sp. nov. known to date from Col de Tanatana in Parc National Andohahela, Toliara. Major workers of both taxa are very similar and can be separated based on slight difference in setosity of lateral sides of head (which is denser and shorter in Pheidole lavasoa sp. nov.) and shape of hypostomal teeth (P. lavasoa sp. nov. has inner hypostomal teeth with rounded apex and outer hypostomal teeth are dentate and indistinctly directed outward). A better resource for species separation are minor workers. Minor workers of Pheidole lavasoa sp. nov. lack transverse rugulae on vertex and frons and their frons have sparse, short, and longitudinal rugulae, mesosoma is entirely smooth, and body is yellowish brown. Diagnosis. Moderately large species. Major workers. Head in full-face view suboval and not widening posteriorly, with anterior and posterior sides slightly convex, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with moderately dense, short, subdecumbent to suberect pilosity; medial part of frons with thick, longitudinal, interrupted, and moderately dense rugae, interspaces rugulate; occipital lobes smooth and shiny; area posterolateral from eyes smooth and shiny; scape, when laid back, exceeding the midlength of head by one-fifth of its length; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth dentate, wider than and approximately as high as inner teeth; inner and outer hypostomal teeth closely spaced and connected by indistinct concavity; promesonotum predominantly smooth with sparse and moderately thick, irregular to transverse rugae on lateral sides; anepisternum, katepisternum, and propodeum finely rugofoveolate; katepisternum with smooth notch; body yellowish orange. Minor workers. Head foveolate; vertex, area posterolateral from eyes smooth; scape, when laid back, exceeding the posterior head margin by one-fifth of its length; promesonotum moderately low and short; promesonotal groove present; propodeal spines small, triangular; mesosoma smooth; propodeum and sometimes katepisternum with sparse foveolae; body orange to yellow. Head. In full-face view sub-oval, not widening posteriorly, with anterior and posterior sides slightly convex (Fig. 38B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with moderately dense, short, subdecumbent to suberect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with thick, longitudinal, interrupted, and moderately dense rugae, interspaces rugulate, rugae directed slightly outward on posteromedial part; lateral sides with thick, dense, and longitudinal rugae with distinctly rugulate interspaces, rugae more irregular on the posterolateral parts. Occipital lobes smooth and shiny. Area posterolateral from eyes smooth and shiny. Gena with relatively sparse and thick longitudinal rugae and smooth to indistinctly rugulate interspaces. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina absent; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by one-fifth of its length; pilosity subdecumbent to erect (Fig. 38B, D). Inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth dentate, wider than and approximately as high as inner teeth; inner and outer hypostomal teeth closely spaced and connected by indistinct concavity (Fig. 63T). Mesosoma. In lateral view, promesonotum short, angular, and moderately low, posterior mesonotum moderately steep, mesonotal process indistinct, tuberclelike; promesonotal groove absent; metanotal groove absent; propodeal spines moderate, with moderately narrow base and acute apex; humeral area weakly produced (Fig.  38D). Surface shiny; promesonotum predominantly smooth with sparse and moderately thick, irregular to transverse rugae on lateral sides; anepisternum, katepisternum, and propodeum finely rugofoveolate; katepisternum with smooth notch. Pilosity moderately dense, long, and erect (Fig. 38D, F). Petiole. Shiny with sparse foveolae; node finely foveolate, triangular, with rounded and thick apex, in rear view node dorsoventrally slightly concave; pilosity moderately sparse and erect (Fig. 38D, F). Postpetiole. Shiny and foveolate; dorsum with reduced sculpture and smooth notch; in dorsal view oval, lateral margins medially with two moderately large dentate projections; pilosity long, moderately sparse, and erect (Fig. 38D, F). Gaster. Shiny and smooth; pilosity moderately dense, moderately long, and erect (Fig. 38D, F). Colour. Yellowish orange with yellow legs (Fig. 38D, F).  Head. Cephalic margin relatively straight (Fig. 38A). Pilosity relatively sparse, moderately long, decumbent to subdecumbent. Sculpture shiny and foveolate; vertex, and area posterolateral from eyes smooth; antennal sockets with few thick, curved outward rugae and foveolate interspaces. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, exceeding the posterior head margin by one-fifth of its length; pilosity dense, suberect to erect (Fig. 38A, C). Meso-soma. In lateral view, promesonotum moderately low and short, arched; promesonotal groove present; metanotal groove distinct; propodeal spines small, triangular (Fig.  38C). Sculpture shiny and smooth; propodeum and sometimes katepisternum with sparse foveolae. Pilosity very sparse, moderately long, and erect (Fig. 38C, E). Gaster. With sparse, erect pilosity (Fig. 38C, E). Colour. Orange to yellow (Fig. 38C, E).

Pheidole litigiosa
Biology. The species was collected between 1317-1409 m in elevation. Biology unknown.
Comments. Pheidole litigiosa Forel is a member of a group of species characterised by distinctly reduced head sculpture in major workers with occipital lobes entirely or predominantly smooth, area posterolateral from eyes partially or entirely smooth and shiny or with reduced sculpture and smooth notches. The group consists of four species: P. litigiosa, P. masoandro sp. nov., P. gracilis sp. nov., and P. tampony sp. nov. Pheidole litigiosa is the only member of this group known from the Antananarivo prefecture. Morphologically P. litigiosa is most similar to P. masoandro sp. nov. known from Anosyenne Mts. in Toliara. Its major workers can be separated based on medial part of frons with thick, longitudinal, interrupted, and moderately dense rugae with rugulate interspaces, moderately dense, short, subdecumbent to suberect pilosity on sides of the head, and having outer hypostomal teeth dentate, wider than and approximately as high as inner teeth; minor workers have indistinct promesonotal groove, propodeal spines small and triangular, and frons lacking additional, short rugae. Despite strong morphological differences in major workers, minor workers of P. litigiosa are extremely similar to those of P. sikorae and P. antranohofa sp. nov. and can be separated based on lack of additional, short rugae.  (CASC). Paratypes. • 6w., 1s.; same data as for holotype, CASENT0455920, CASENT0455921, CASENT0455922 (CASC, MHNG, PBZT).

Pheidole mahamavo
Diagnosis. Moderately large species. Major workers. Head in full-face view suboval, not widening posteriorly, with anterior and posterior sides slightly convex, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with very dense, long, suberect to erect pilosity; medial part of frons with thick, interrupted, dense, and longitudinal rugae with smooth interspaces; lateral sides of frons with thick and denser rugae with smooth to indistinctly rugulate interspaces, anterolateral sides with longitudinal rugae; posterolateral sides with rugae more irregular; occipital lobes and area posterolateral from eyes without smooth notches; scape, when laid back, exceeding the midlength of head by two-fifths of its length; inner hypostomal teeth distinct, large, and wide, closely spaced, triangular with apex directed upward; outer hypostomal teeth lobe-like, narrower, and approximately as high as inner teeth, apex directed upward; inner and outer hypostomal teeth closely spaced and not connected by concavity; mesosoma rugofoveolate; pronotum with reduced rugofoveolae and with additional sparse and thin transverse rugae; katepisternum with smooth notch; gaster smooth; body brown. Minor workers. Head foveolate; vertex with fading foveolae and additional transverse rugae; frons with distinct and sparse, longitudinal rugae; area posterolateral from eyes smooth; scape, when laid back, exceeding the posterior head margin by onethird of its length; promesonotum low and moderately long; promesonotal groove present; propodeal spines minute, triangular; mesosoma foveolate; promesonotal dorsum and katepisternum with smooth notches; body brown.
Etymology. From the type locality. Biology. The species was collected at 900 m in elevation, in montane rainforest. Nest was located in leaf litter.
Comments. Pheidole mahamavo sp. nov. is most similar to sympatric P. veteratrix, and to P. trichotos sp. nov., and P. anomala sp. nov., known from a remote locality in Antsiranana prefecture. Major workers of P. mahamavo sp. nov. can be easily separated from those three taxa based on presence of thick, interrupted, dense, and longitudinal rugae with smooth interspaces on medial frons and more longitudinal rugae on lateral sides of frons; minors can be separated from P. veteratrix and P. trichotos sp. nov. based on presence of distinct and arcing rugae on vertex and sparser sculpture on pronotal dorsum, and from P. anomala sp. nov. based on darker brown body colouration, sparser sculpture on propodeum, and presence of distinct and arcing rugae on vertex.  (CASC). Paratype. • 1w.; same data as for holotype, CASENT0809553 (CASC).

Pheidole mainty
Diagnosis. Moderately large species. Major workers. Head in full-face view sub-oval and slightly widening posteriorly, with anterior and posterior sides slightly convex, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with very dense, moderately long, suberect to erect pilosity; medial part of frons with thick, interrupted, dense, and longitudinal rugae with smooth to indistinctly rugulate interspaces; occipital lobes and area posterolateral from eyes without smooth notches; scape, when laid back, exceeding the midlength of head by one-fifth of its length; inner hypostomal teeth distinct, moderately large, and narrow, closely spaced, triangular with apex directed slightly inward; outer hypostomal teeth lobe-like, wider and higher than inner teeth, apex directed outward; inner and outer hypostomal teeth closely spaced and not connected by concavity; mesosoma rugofoveolate; katepisternum with smooth notch; dorsal side of promesonotum with reduced and sparser sculpture; gaster smooth; body black. Minor workers. Head foveolate; vertex with fading foveolae; frons with distinct and sparse, longitudinal rugae; area posterolateral from eyes smooth; scape, when laid back, exceeding the posterior head margin by one-third of its length; promesonotum low and moderately long; promesonotal groove present; propodeal spines small, triangular; mesosoma foveolate; promesonotal dorsum, katepisternum, and propodeum predominantly smooth; body black. Head. In full-face view sub-oval, slightly widening posteriorly, with anterior and posterior sides convex (Fig. 40B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth invisible. Sides of the head with very dense, moderately long, suberect to erect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with thick, interrupted, dense, and longitudinal rugae with smooth to indistinctly rugulate interspaces; lateral sides of frons with denser, thick, and longitudinal rugae, interspaces with dense, thick, and distinct rugulae. Occipital lobes with sparser and fading rugae and indistinctly rugulate to smooth interspaces. Area posterolateral from eyes with dense, thick, longitudinal rugae with distinctly rugulate interspaces, sculpture slightly fading posteriorly. Gena with relatively sparse, thick, longitudinal rugae and indistinctly rugulate interspaces. Centre of clypeus smooth with few longitudinal rugulae and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina present; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by one-fifth of its length; pilosity subdecumbent to erect (Fig. 40B, D). Inner hypostomal teeth distinct, moderately large, and narrow, closely spaced, triangular with apex directed slightly inward; outer hypostomal teeth lobe-like, wider and higher than inner teeth, apex directed outward; inner and outer hypostomal teeth closely spaced and not connected by concavity (Fig. 63V). Mesosoma. In lateral view, promesonotum short, angular, and moderately low, posterior mesonotum moderately steep, mesonotal process indistinct, tubercle-like; promesonotal groove absent; metanotal groove absent; propodeal spines moderately long, relatively wide, and with acute apex; humeral area weakly produced (Fig. 40D). Surface shiny and rugofoveolate; katepisternum with smooth notch; dorsal side of promesonotum with reduced and sparser sculpture. Pilosity moderately dense, long, and erect (Fig. 40D, F). Petiole. Shiny with sparse foveolae; node finely smooth, triangular, with rounded and thick apex, in rear view node dorsoventrally slightly convex; pilosity moderately sparse and erect (Fig. 40D, F). Postpetiole. Shiny and foveolate; dorsum smooth; in dorsal view oval, lateral margins medially with two very small and dentate projections; pilosity long, moderately sparse, and erect (Fig. 40D, F). Gaster. Shiny and smooth; pilosity moderately dense, long, and erect (Fig. 40D, F). Colour. Black, antenna and legs brownish (Fig. 40D, F). Head. Cephalic margin slightly convex (Fig. 40A). Pilosity relatively sparse, short, subdecumbent. Sculpture shiny and foveolate; vertex with fading foveolae; frons with distinct, sparse, and longitudinal rugae; area posterolateral from eyes smooth; antennal sockets with few indistinct, curved outward rugae and foveolate interspaces. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, exceeding the posterior head margin by one-third of its length; pilosity dense, subdecumbent to erect (Fig. 40A, C). Mesosoma. In lateral view, promesonotum low and moderately long, arched; promesonotal groove indistinct; metanotal groove distinct; propodeal spines small and triangular (Fig. 40C). Sculpture shiny and foveolate; promesonotal dorsum, katepisternum and propodeum predominantly smooth. Pilosity sparse, moderately long, and erect (Fig. 40C, E). Gaster. With sparse, erect pilosity (Fig.  40C, E). Colour. Black, with legs, gaster, and antenna yellowish brown (Fig. 40C, E).
Etymology. Malagasy for black in reference to black body colouration. Biology. The species was collected at 2100 m in elevation, in montane shrubland. Nest was located under rootmats on stones.
Comments. Pheidole mainty sp. nov. is a member of a group of taxa characterised by dark body colouration that in major workers ranges from brownish black to black and in minor workers ranges from black (head and mesosoma) to dark brown with body predominantly foveolate (only in dark brown specimens). The group consists of three species: P. alina sp. nov., P. trichotos sp. nov., and P. mainty sp. nov. All members of this group are sympatric and their distribution is limited to the northernmost parts of the island, predominantly in Antsiranana prefecture. Major workers of Pheidole mainty sp. nov. differ from P. trichotos sp. nov. in medial part of frons with thick, interrupted, dense, and longitudinal rugae with smooth to indistinctly rugulate interspaces, base of first gastral tergite smooth and indistinct, bulge-like inner hypostomal teeth; from P. alina sp. nov. in sides of the head with very dense, moderately long, suberect to erect pilosity, distinct, triangular inner hypostomal teeth, and wide and moderately long propodeal spines. Minor workers of P. mainty sp. nov. differ from P. trichotos sp. nov. and P. alina sp. nov. in entirely smooth area posterolateral from eyes and predominantly smooth promesonotal dorsum, katepisternum, and propodeum.

Diagnosis. Moderately large species. Major workers.
Head in full-face view suboval, not widening posteriorly, with anterior and posterior sides slightly convex, in lateral view sub-oval, ventral and dorsal faces convex; sides of the head with moderately dense, long, suberect to erect pilosity; medial frons with moderately sparse, thick rugae, anteriorly longitudinal and interrupted, posteromedially rugae irregular, interspaces shiny and predominantly smooth, with sparse and indistinct, irregular rugulae; lateral sides with rugae that are longitudinal anteriorly to irregular posteriorly, thick and relatively sparse rugae with distinctly rugoreticulate interspaces; occipital lobes and area posterolateral from eyes never smooth; scape, when laid back, exceeding the midlength of head by two-fifths of its length; inner hypostomal teeth distinct, small, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, wider and higher than inner hypostomal teeth, apex directed outward; inner and outer hypostomal teeth closely spaced, connected by indistinct concavity; pronotum and mesonotum predominantly smooth with indistinct rugofoveolae and transverse rugae; katepisternum, anepisternum, and propodeum with sparse rugofoveolae; body yellow. Minor workers. Head foveolate; medial part of frons and vertex with strongly reduced sculpture and predominantly smooth; area posterolateral from eyes smooth; scape, when laid back, surpassing the posterior head margin by two-fifths of its length; promesonotum moderately low and short; promesonotal groove absent; propodeal spines very small and triangular; mesosoma smooth; body yellow. Head. In full-face view sub-oval, not widening posteriorly, with anterior and posterior sides slightly convex (Fig. 41B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with moderately dense, long, suberect to erect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with moderately sparse, thick rugae, anteriorly longitudinal and interrupted, posteromedially rugae irregular, interspaces shiny and predominantly smooth, with sparse and indistinct irregular rugulae; lateral sides with rugae longitudinal anteriorly to irregular posteriorly, thick and relatively sparse rugae with distinctly rugoreticulate interspaces. Occipital lobes with sparse, thick, and irregular rugae; interspaces smooth. Gena with relatively dense, thick, and longitudinal rugae and smooth interspaces. Area posterolateral from eyes predominantly smooth, with sparse and indistinct rugoreticulae. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina present; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by two-fifths of its length; pilosity subdecumbent to erect (Fig. 41B, D). Inner hypostomal teeth distinct, small, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, wider and higher than inner hypostomal teeth, apex directed outward; inner and outer hypostomal teeth closely spaced, connected by indistinct concavity (Fig. 63W). Mesosoma. In lat-eral view, promesonotum short, angular, and moderately high, posterior mesonotum moderately steep, mesonotal process indistinct, tubercle-like; promesonotal groove absent; metanotal groove indistinct; propodeal spines moderately long, moderately wide, with acute apex; humeral area laterally weakly produced (Fig. 41D). Surface shiny; pronotum and mesonotum predominantly smooth with indistinct rugofoveolae and transverse rugae; katepisternum, anepisternum, and propodeum with sparse rugofoveolae. Pilosity relatively dense, long, and erect (Fig. 41D, F). Petiole. Shiny with fine and dense rugofoveolae; peduncle; node partially smooth, low, triangular, with rounded and thin apex, in rear view node dorsoventrally slightly convex; pilosity moderately sparse and erect (Fig. 41D, F). Postpetiole. Shiny and smooth; in dorsal view oval, lateral margins medially with two dentate projections; pilosity long, moderately sparse, and erect (Fig. 41D, F). Gaster. Shiny and smooth; pilosity moderately dense, long, and erect (Fig. 41D, F). Colour. Yellow; mandibles and gaster slightly darker (Fig. 41D, F). Head. Cephalic margin indistinctly concave or straight (Fig. 41A). Pilosity relatively sparse, long, decumbent to suberect. Sculpture foveolate; medial part of frons and vertex with strongly reduced sculpture and predominantly smooth; area posterolateral from eyes smooth. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, surpassing the posterior head margin by two-fifths of its length; pilosity dense, subdecumbent to erect (Fig. 41A, C). Mesosoma. In lateral view, promesonotum moderately low and short, arched; promesonotal groove absent; metanotal groove present and distinct; propodeal spines very small and triangular (Fig. 41C). Sculpture smooth. Pilosity very sparse, moderately long, and erect (Fig. 41C, E). Postpetiole. Short, low, and relatively flat; with few short, erect setae (Fig. 41C, E). Gaster. With sparse, erect pilosity (Fig. 41C, E). Colour. Yellow, vertex slightly darker (Fig. 41C, E).
Etymology. Malagasy for "to shine" or "to give light" in reference to bright body colouration.
Biology. The species was collected at 1460 m in elevation, in rainforest. Nests were in soil.
Comments. Pheidole mamiratra sp. nov. is a member of a group of species characterised by body colouration that is bright and yellow to orange in majors and yellow in minors, sub-oval, not widening posteriorly head with sides not convex or convex indistinctly, and medial part of frons with longitudinal and rugae interrupted anteriorly and distinctly irregular posteriorly. The group includes three taxa: P. vony sp. nov., P. befotaka sp. nov., and P. mamiratra sp. nov. Pheidole mamiratra sp. nov. is known from Station Forestière Angavokely in Antananarivo and its distribution does not overlap with two remaining members of the group. Morphologically P. mamiratra sp. nov. is most similar to P. vony sp. nov., known only from two localities in Toamasina: Montagne d'Anjanaharibe and Montagne d'Akirindro. Major workers of P. mamiratra sp. nov. differ from P. vony sp. nov. in medial part of frons with moderately sparse and thick rugae and inner hypostomal teeth small and triangular with rounded apex directed upward and outer hypostomal teeth lobe-like, wider and higher than inner hypostomal teeth; minors differ in less distinctly foveolate head sculpture with predomi-nantly smooth frons and entirely smooth area posterolateral from eyes. Additionally, minor and major workers of P. mamiratra sp. nov. can be also confused with P. sparsa sp. nov., known from Bemanevika in Mahajanga, and sympatric P. hazo sp. nov., described from the vicinity of Antananarivo. Majors of P. mamiratra sp. nov. differ from P. sparsa sp. nov. and P. hazo sp. nov. in median frons with distinctly irregular rugae and more irregular sculpture on later sides of frons and outer hypostomal teeth wider and higher than inner hypostomal teeth; additionally, majors of sympatric P. hazo sp. nov. differ in lack of smooth notches on katepisternum. Minor workers of P. mamiratra sp. nov. differ from P. sparsa sp. nov. and P. hazo sp. nov. in medial part of frons and vertex with strongly reduced sculpture, predominantly smooth vertex, and lack of additional, indistinct rugulae on head.  (CASC).

Pheidole manantenina
Diagnosis. Moderately large species. Major workers. Head in full-face view suboval, not widening posteriorly, with anterior and posterior sides convex, slightly narrowing posteriorly, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with dense, long, erect pilosity; medial part of frons with moderately sparse, thick, interrupted, and longitudinal rugae, on posteromedial part rugae directed outward, interspaces with sparse and indistinct rugofoveolae or smooth; lateral sides with irregular to longitudinally irregular and thick rugae with distinctly rugofoveolate interspaces; occipital lobes and area posterolateral from eyes without smooth notches; scape, when laid back, exceeding the midlength of head by two-fifths of its length; inner hypostomal teeth distinct, moderate, closely spaced, triangular, with rounded apex slightly directed inward; outer hypostomal teeth lobe-like, wider than inner hypostomal teeth and approximately the same height, apex directed outward; inner and outer hypostomal teeth closely spaced but not connected; mesosoma with fine rugofoveolae, pronotal dorsum with weaker sculpture and usually its medial part with smooth notch; gaster smooth; body dark orange to brown. Minor workers. Head smooth with sparse, irregular to longitudinal, thick rugae on anterior frons and gena, interspaces smooth to indistinctly foveolate; scape, when laid back, surpassing the posterior head margin by one-fifth of its length; promesonotum moderately high and short, arched; promesonotal groove present; propodeal spines small and triangular; pronotum and mesonotum smooth and sometimes with indistinct rugofoveolae on lateral sides, anepisternum, katepisternum, and propodeum with indistinct and moderately dense rugofoveolae, katepisternum sometimes with smooth notch; body brown to dark brown.
Etymology. From the type locality. Biology. The species was collected between 1575-2000 m in elevation, in montane shrublands and montane rainforest. Nests were located in rotten logs, under moss, in root mats.
Comments. Pheidole manantenina sp. nov. is known from Parc National de Marojejy in Antsiranana and morphologically is most similar to parapatric and widespread P. sofia sp. nov. Majors of P. manantenina sp. nov. differ from P. sofia sp. nov. in medial part of frons with smooth to indistinctly rugofoveolate interspaces, lateral sides of frons with more irregular rugae, body brownish to dark orange, and promesonotum with reduced sculpture; minor workers can be separated based on more reduced sculpture on head, and mesosoma predominantly smooth with indistinct rugofoveolae.  (CASC). Paratype. • 1w.; same data as for holotype; CASENT0923293 (CASC).
Diagnosis. Moderately large species. Major workers. Head in full-face view sub-oval and not widening posteriorly, with anterior and posterior sides slightly convex, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with very dense, long, erect pilosity; medial part of frons with moderately dense, thick, interrupted longitudinal rugae, interspaces smooth; occipital lobes smooth and shiny; area posterolateral from eyes with reduced sculpture and smooth notch; scape, when laid back, exceeding the midlength of head by approximately two-fifths of its length; inner hypostomal teeth distinct, moderately high, closely spaced, triangular, with rounded apex slightly directed outward; outer hypostomal teeth lobe-like, wider and higher than inner hypostomal teeth, apex directed outward; inner and outer hypostomal teeth closely spaced but not connected; mesosoma predominantly smooth, indistinct, thin, sparse, and irregular rugae occur on lateral sides; body yellow. Minor workers. Medial part of frons with sparse and fading foveolae and short, longitudinal rugae; lateral sides with thicker and denser foveolae and longitudinal, interrupted, and thick rugae; area posterolateral from eyes smooth; scape, when laid back, surpassing the posterior head margin by one-fifth of its length; promesonotum moderately low and short; promesonotal groove present; propodeal spines minute and triangular; mesosoma smooth with indistinct foveolae on posterior katepisternum; body yellow.
Etymology. Malagasy for sun, in reference to bright yellow body colouration. Biology. The species was collected at 1125 m in elevation, in rainforest. Nest was located in root mat.
Comments. Pheidole masoandro sp. nov. is a member of a group of species characterised by distinctly reduced head sculpture in major workers with occipital lobes entirely or predominantly smooth, area posterolateral from eyes partially or entirely smooth and shiny or with reduced sculpture and smooth notches. The group consists of four species: P. litigiosa, P. masoandro sp. nov., P. gracilis sp. nov., and P. tampony sp. nov. Pheidole masoandro sp. nov. is the only member of this group known from the Anosyenne Mts. in Toliara. Morphologically P. masoandro sp. nov. is most similar to P. litigiosa distributed in the Antananarivo prefecture. Its major workers can be separated based on medial part of frons with moderately dense, thick, interrupted, and longitudinal rugae and smooth interspaces, sides of the head with very dense, long, erect pilosity, and outer hypostomal teeth lobe-like, wider and higher than inner hypostomal teeth with apex directed outward; minor workers have distinct promesonotal groove, their propodeal spines are minute and triangular, and frons have additional short rugae. Despite strong morphological differences in major workers, minor workers of P. masoandro sp. nov., P. sikorae and P. antranohofa sp. nov. are indistinguishable.  (CASC).

Pheidole mavohavoana
Diagnosis. Moderately large species. Major workers. Head in full-face view suboval, widening posteriorly, with anterior and posterior sides convex, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head very dense, short, suberect to erect pilosity; medial part of frons with thick, longitudinal, and dense rugae, interspaces predominantly smooth to indistinctly rugulate, rugae more irregular and directed slightly outward on posteromedial part; lateral sides with thick, dense, and irregular rugae with sparsely rugulate interspaces; area posterolateral from eyes without smooth notches; scape, when laid back, exceeding the midlength of head by three-fifths of its length; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, distinctly lower and narrower than inner teeth; inner and outer hypostomal teeth closely spaced and not connected by concavity; mesosoma rugofoveolate; dorsal promesonotum and katepisternum with sparser rugofoveolae; gaster smooth with very dense pilosity; body orange. Minor workers. Head smooth; lateral sides of frons with longitudinal, short, and thick rugae; vertex with very short, sparse, and transverse rugae; scape, when laid back, exceeding the posterior head margin by two-fifths of its length; promesonotum moderately low and moderately long; promesonotal groove present; propodeal spines very small and triangular; mesosoma smooth; dorsal promesonotum with very sparse and transverse rugae; propodeum with sparse, irregular, and indistinct rugulae; body yellow. Head. In full-face view sub-oval, distinctly widening posteriorly, with anterior and posterior sides convex (Fig. 44B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with very dense, short, suberect to erect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with thick, longitudinal and dense rugae, interspaces predominantly smooth to indistinctly rugulate, rugae more irregular and directed slightly outward on posteromedial part; lateral sides with thick, dense, and irregular rugae with sparsely rugulate interspaces. Occipital lobes with dense, irregular rugae and sparsely rugulate interspaces. Area posterolateral from eyes with weaker sculpture. Gena with relatively sparse, thick, and longitudinal rugae and distinctly rugulate interspaces. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina absent; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by three-fifths of its length; pilosity subdecumbent to erect (Fig. 44B, D). Inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, distinctly lower and narrower than inner teeth; inner and outer hypostomal teeth closely spaced and not connected by concavity (Fig. 64B). Mesosoma. In lateral view, promesonotum short, angular, and moderately high, posterior mesonotum steep, mesonotal process indistinct, tubercle-like; promesonotal groove absent; metanotal groove indistinct; propodeal spines moderately long, with moderately wide base and acute apex; humeral area poorly produced (Fig. 44D). Surface shiny and rugofoveolate; dorsal promesonotum and katepisternum with sparser rugofoveolae. Pilosity sparse, long, and erect (Fig. 44D, F). Petiole. Shiny with sparse foveolae; node finely foveolate, triangular, with rounded and thick apex, in rear view node dorsoventrally convex; pilosity moderately sparse and erect (Fig. 44D, F). Postpetiole. Shiny and foveolate; dorsum with reduced sculpture and smooth notch; in dorsal view oval, lateral margins medially with two dentate projections; pilosity long, moderately sparse, and erect (Fig.  44D, F). Gaster. Shiny and smooth; pilosity very dense, moderately short, and erect ( Fig. 44D, F). Colour. Yellowish orange with yellow legs and gaster (Fig. 44D, F). Head. Cephalic margin slightly convex (Fig. 44A). Pilosity relatively dense, moderately long, decumbent to subdecumbent. Sculpture shiny and smooth; lateral sides of frons with longitudinal, short, and thick rugae; vertex with very short, sparse, and transverse rugae; antennal sockets with few thick, curved outward rugae and smooth interspaces. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, exceeding the posterior head margin by twofifths of its length; pilosity dense, suberect to erect (Fig. 44A, C). Mesosoma. In lateral view, promesonotum moderately low and moderately long, arched; promesonotal groove present; metanotal groove distinct; propodeal spines very small and triangular (Fig. 44C). Sculpture shiny and smooth; dorsal promesonotum with very sparse and transverse rugae; propodeum with sparse, irregular, and indistinct rugulae. Pilosity sparse, moderately long, and erect (Fig. 44C, E). Gaster. With dense, erect pilosity (Fig. 44C, E). Colour. Yellow (Fig. 44C, E).
Etymology. Malagasy for yellow and hill in reference to body colouration and a habitat occupied by the species.
Biology. The species was collected between 900-1075 m in elevation, in montane rainforest. Nests were located in rotten logs and under stones.
Comments. Pheidole mavohavoana sp. nov. has very distinct major and minor workers. The species is known from two localities: Andrambovato in Fianarantsoa and Parc National d'Andohahela in Toliara. Morphologically P. mavohavoana sp. nov. is most similar to P. antranohofa sp. nov., a species known from a remote locality in Antsiranana. Major workers of P. mavohavoana sp. nov. differ from those of P. antranohofa sp. nov. in very dense, short, suberect to erect pilosity on sides of the head with, thick, dense, and irregular rugae with sparsely rugulate interspaces on lateral sides of frons, very dense pilosity on gaster, and reduced outer hypostomal teeth; minor workers can be separated based on predominantly smooth head lacking foveolae, moderately low and moderately long promesonotum, and dense pilosity on gaster.  -23.83517, 46.96367;alt. 940 m;14 Nov 2006; rainforest, ex rotten log; BLF14842; CASENT0119419 (CASC). Paratype. • 1w.; same data as for holotype, CASENT0923275 (CASC).
Diagnosis. Minute species. Major workers. HL < 0.9 mm and WL < 0.7 mm; head in full-face view sub-oval, slightly widening posteriorly, with anterior and posterior sides convex, in lateral view sub-oval; ventral and dorsal faces convex; body blackish brown; sides of head with moderately dense, moderately short, suberect pilosity; entire head distinctly sculptured, medial part of frons with thick, longitudinal, and dense rugae and distinctly rugulate interspaces, rugae more irregular and directed slightly outward on posteromedial part; scape, when laid back, exceeding the midlength of head by one-fifth of its length; mesosoma distinctly foveolate, promesonotum with additional sparse, thin, and irregular rugae on dorsum; katepisternum and propodeum with sparser foveolae; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, wider than inner teeth and approximately the same height; inner and outer hypostomal teeth closely spaced and not connected by concavity; base of first gastral tergite smooth. Minor workers. HL < 0.5 mm and WL < 0.6 mm, scape, when laid back, exceeding the posterior head margin by less than one-fifth of its length; propodeal spines reduced to small tubercles; head relatively oval; frons with sparse and moderately thick, short, and predominantly longitudinal rugulae fading medially; vertex with transverse, sparse, moderately thick, and short rugulae; area posterolateral from eyes smooth; body dark yellow; mesosoma smooth.
Etymology. From the type locality. Biology. The species was collected at 940 m in elevation, in rainforest. Nest was located in a rotten log.
Comments. Pheidole midongy sp. nov. belongs to the group of species characterised by small body size (major workers: HL < 1.05 mm, WL < 0.9 mm and minor workers HL < 0.5 mm, WL < 0.6 mm), sub-oval, slightly widening posteriorly head with anterior and posterior sides convex in major workers, and minor workers with yellow to brown body colouration and head foveolate or predominantly smooth and relatively oval. The group includes six species: P. havoana sp. nov., P. kely sp. nov., P. parvula sp. nov., P. parvulogibba sp. nov., P. volontany sp. nov., and P. midongy sp. nov. Because of dark body colouration P. midongy sp. nov., described form Parc National Befotaka-Midongy in Fianarantsoa, is most similar to P. volontany sp. nov., known from Forêt Classée d'Analavelona in Toliara. Major workers of P. midongy sp. nov. differ from P. volontany sp. nov. in frons with thick, longitudinal, and dense rugae and distinctly rugulate interspaces, and sides of the head with moderately dense, moderately short, and suberect pilosity; minor workers differ in frons with sparse and moderately thick, short, and predominantly longitudinal rugulae, vertex with transverse, sparse, and moderately thick short rugulae, oval head shape, and brighter body colouration.  (CASC).

Etymology.
Greek for small in reference to the body size. Biology. The species was collected between 80-450 m in elevation, in rainforest and tropical dry forest. Nests were located in rotten logs and under tree bark.
Comments. Pheidole mikros sp. nov. belongs to the group of species characterised by small body size (major workers: HL < 1.05 mm, WL < 0.9 mm and minor workers HL < 0.5 mm, WL < 0.6 mm), head elongate and not widening posteriorly in major workers, and minor workers with head predominantly smooth and relatively rectangular, and body colouration yellow to brown. The group includes four species: P. flavominuta sp. nov., P. nitidobruna sp. nov., P. mikros sp. nov., and P. beanka sp. nov. Pheidole mikros sp. nov. is known from the area between Andapa and Antisiranana and is parapatric with Pheidole nitidobruna sp. nov. described from Makirovana forest in Antsiranana. Major workers of P. mikros sp. nov. can be separated from P. nitidobruna sp. nov. by predominantly indistinctly rugulate interspaces on frons, occipital lobes with distinctly foveolate or rugoreticulae interspaces, and absence of smooth notches on lateral sides of promesonotum. Minor workers of P. mikros sp. nov. can be separated from P. nitidobruna sp. nov. based on presence of sculpture on vertex and frons and presence of small, triangular propodeal spines. However, the morphology of P. mikros sp. nov. is most similar to P. beanka sp. nov., which is known from Réserve forestière Beanka in Mahajanga. Pheidole mikros sp. nov. differs from P. beanka sp. nov. by the combination of the following characters: major workers have medial part of frons with indistinctly rugulate interspaces and their propodeal spines are moderately long; minor workers have lateral sides of frons with fine, sparse, and irregular rugulae, mesosoma covered by a sparse and moderately thick network of irregular rugulae, and body is yellowish brown.  (CASC). Paratypes. • 2w., 1m.; same data as for holotype, CASENT0825255, CASENT0923288 (CASC, MHNG).
Diagnosis. Moderately large species. Major workers. Head in full-face view suboval and slightly widening posteriorly, with anterior and posterior sides slightly convex, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with moderately sparse, long, suberect to erect pilosity; with thick, interrupted, dense, and longitudinal rugae, posteromedial frons with rugae irregular, interspaces with sparse rugofoveolate; lateral sides of frons with dense, thick, predominantly irregular rugae with few distinct, longitudinal rugae, interspaces with sparse rugulae; occipital lobes, area posterolateral from eyes without smooth notches; scape, when laid back, exceeding the midlength of head by two-fifths of its length; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, wider than and approximately as high as inner teeth, apex directed upward; inner and outer hypostomal teeth closely spaced and not connected by concavity; mesosoma rugofoveolate; pronotum with additional thin, moderately dense, and transverse rugae; gaster smooth with slightly shagreened base of first tergite; body brown. Minor workers. Head foveolate; median frons with short and indistinct longitudinal rugulae; area posterolateral from eyes with weaker sculpture; scape, when laid back, exceeding the posterior head margin by one-third of its length; promesonotum low and moder-ately long, arched; promesonotal groove absent; propodeal spines small and triangular; mesosoma with sparse foveolae; dorsal promesonotum and medial parts of lateral sides of pronotum, propodeum, and katepisternum with smooth notches; body brown.
Etymology. Malagasy for watercourse in reference to the river located close to the sampling site of the species.
Biology. The species was collected at 450 m in elevation, in rainforest. Nest was located in a rotten log.
Comments. Pheidole mivory sp. nov., described from Parc National de Marojejy in Antsiranana, has major workers with dense and thick rugae that are anteromedially longitudinal and posteromedially irregular, with distinctly rugofoveolate interspaces, and brown body colouration. Morphologically it is most similar to the parapatric P. joffreville sp. nov., known from Parc National Montagne d'Ambre in Antsiranana. Majors of both taxa are extremely similar and species separation should be supported by or based exclusively on minors. Majors of P. mivory sp. nov. differ from P. joffreville sp. nov. in indistinctly rugofoveolate interspaces on frons, and presence of longitudinal rugae on lateral sides of frons, and indistinctly shagreened sculpture of first gastral tergite; minor workers differ in mesosoma with sparse foveolae with dorsal promesonotum and medial parts of lateral sides of pronotum, propodeum, and katepisternum with smooth notches.  (CASC). Paratype. • 1w.; same data as for holotype, CASENT0245024 (CASC).
Diagnosis. Minute species. Major workers. HL < 0.9 mm and WL < 0.8 mm; head in full-face view elongate, not widening posteriorly with posterior sides slightly convex, in lateral view sub-oval and short with convex dorsal and ventral sides; body brown; sides of head with moderately sparse, moderately long, suberect to erect pilosity; entire head distinctly sculptured, medial part of frons with thick and longitudinal rugae and smooth to indistinctly rugulate interspaces, occipital lobes with dense and irregular rugae with indistinctly rugoreticulate interspaces; scape, when laid back, exceeding the midlength of head by one-fifth of its length; lateral sides of promesonotum with smooth notches; inner hypostomal teeth distinct, moderate, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, lower and wider than inner teeth; inner and outer hypostomal teeth closely spaced and not connected by concavity; base of first gastral tergite shagreened. Minor workers. HL < 0.45 mm and WL < 0.5 mm, scape, when laid back, exceeding the posterior head margin by one-fifth of its length; propodeal spines reduced to small tubercles; head relatively rectangular; body yellowish brown; head with frons and vertex smooth; mesosoma smooth.
Etymology. Latin for smooth and brown in reference to smooth sculpture and dark body colouration.
Biology. The species was collected at 550 m in elevation, in rainforest. Nest was located in a rotten log.
Comments. Pheidole nitidobruna sp. nov. belongs to the group of species characterised by small body size (major workers: HL < 1.05 mm, WL < 0.9 mm and minor workers HL < 0.5 mm, WL < 0.6 mm), major workers with head elongate and not widening posteriorly, and minor workers with predominantly smooth and relatively rectangular head and yellow to brown body colouration. The group includes four species: P. flavominuta sp. nov., P. nitidobruna sp. nov., P. mikros sp. nov., and P. beanka sp. nov. Pheidole nitidobruna sp. nov. is known only from Makirovana forest in Antsiranana and is parapatric with P. mikros sp. nov., which is recorded from the area between Andapa and Antisiranana. Major workers of P. nitidobruna sp. nov. can be separated from P. mikros sp. nov. by smooth to indistinctly rugulate interspaces on frons and occipital lobes and presence of smooth notches on lateral sides of promesonotum. Minor workers of P. nitidobruna sp. nov. can be separated from P. mikros sp. nov. based on entirely smooth vertex and frons and presence of propodeal spines reduced to small tubercles. Diagnosis. Minute species. Major workers. HL < 0.9 mm and WL < 0.8 mm; head in full-face view sub-oval, slightly widening posteriorly, with anterior and posterior sides convex, in lateral view sub-oval; ventral and dorsal faces convex; body dark orange; sides of head with moderately dense, moderately long, suberect pilosity; entire head distinctly sculptured, medial part of frons with thick and dense rugae and distinctly rugulate interspaces, rugae predominantly irregular and only centre and basal parts with few longitudinal rugulae; scape, when laid back, exceeding the midlength of head by one-fifth of its length; pronotum distinctly foveolate with additional irregular rugae on dorsum; anepisternum, katepisternum, and propodeum with fine rugulae and smooth interspaces; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, slightly lower and wider than inner teeth; inner and outer hypostomal teeth moderately closely spaced and not connected by concavity; base of first gastral tergite smooth. Minor workers. HL < 0.5 mm and WL < 0.6 mm, scape, when laid back, surpassing the posterior head margin by one-fifth of its length; propodeal spines small and triangular; head relatively oval; body dark yellow; medial frons smooth; lateral sides of frons and vertex with fine, sparse, and irregular rugulae with smooth interspaces; area posterolateral from eyes smooth; mesosoma predominantly smooth with very sparse, fine, and irregular rugulae.
Etymology. Latin for small in reference to the body size. Biology. The species was collected between 750-1490 m in elevation, in montane forest and rainforest. Nests were located in rotten logs and litter.
Comments. Pheidole parvula sp. nov. belongs to the group of species characterised by small body size (major workers: HL < 1.05 mm, WL < 0.9 mm and minor workers HL < 0.5 mm, WL < 0.6 mm), head sub-oval and slightly widening posteriorly with anterior and posterior sides convex in major workers, and minor workers with yellow to brown body colouration and head foveolate or predominantly smooth and relatively oval. The group includes six species: P. havoana sp. nov., P. kely sp. nov., P. parvula sp. nov., P. parvulogibba sp. nov., P. volontany sp. nov., and P. midongy sp. nov. Within this group, P. parvula sp. nov., described form two localities, Réserve Speciale d'Ambohitantely in Antananarivo and Ankerana in Toamasina, is most similar to parapatric P. kely sp. nov. P. parvula sp. nov. may also be confused with two taxa known only from the Anosyenne Mts. in Toliara, P. parvulogibba sp. nov. and P. havoana sp. nov. Minor workers of P. parvula sp. nov. distinctly differ from P. kely sp. nov. and P. havoana sp. nov. in never foveolate head; and from P. parvulogibba sp. nov. in lateral sides of frons and vertex with fine, sparse and irregular rugulae with smooth interspaces. Major workers of P. parvula sp. nov. differ from P. kely sp. nov. and P. parvulogibba sp. nov. by medial part of frons with thick and dense rugae and distinctly rugulate interspaces; and differ from P. havoana sp. nov. in promesonotum foveolate with sparse, thick to moderately thick, transverse to irregular rugae on dorsum and lack of smooth notches. BLF36257; CASENT0704453 (CASC). Paratype. • 1w.; same data as for holotype, CASENT0923274 (CASC).
Diagnosis. Minute species. Major workers. HL < 1.1 mm and WL < 0.9 mm; head in full-face view sub-oval, slightly widening posteriorly, with anterior and posterior sides convex, in lateral view sub-oval; ventral and dorsal faces convex; body yellowish orange; sides of head with moderately dense, moderately long, decumbent to subdecumbent pilosity; entire head distinctly sculptured, medial part of frons with thick, longitudinal, and dense rugae and smooth to indistinctly rugulate interspaces, rugae more irregular and directed slightly outward on posteromedial part; scape, when laid back, reaching the midlength of head; promesonotum foveolate with sparse, thick to moderately thick, transverse to irregular rugae on dorsum; anepisternum, katepisternum, and propodeum with sparser foveolae; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, wider than inner teeth and approximately the same height; inner and outer hypostomal teeth closely spaced and not connected by concavity; base of first gastral tergite smooth. Minor workers. HL < 0.5 mm and WL < 0.6 mm, scape, when laid back, exceeding the posterior head margin by one-fifth of its length; propodeal spines reduced to small tubercles; head relatively oval and entirely smooth; body yellow; mesosoma smooth.
Etymology. Latin for both small and gibbus, in reference to small body size and shape of promesonotum of major workers.
Biology. The species was collected at 750 m in elevation, in montane rainforest. Nest was located under rootmats, on rock.
Diagnosis. Moderately large species. Major workers. Head in full-face view suboval, not widening posteriorly, with anterior and posterior sides slightly convex, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with moderately dense, moderately long, suberect pilosity; medial part of frons with thick, longitudinal, interrupted and dense rugae, interspaces smooth to indistinctly rugulate; lateral sides with thicker, dense and longitudinal to posteriorly slightly irregular rugae with predominantly smooth but sometimes indistinctly rugulate interspaces; occipital lobes and area posterolateral from eyes without smooth notches; scape, when laid back, exceeding the midlength of head by two-fifths of its length; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, wider than and approximately as high as inner teeth; inner and outer hypostomal teeth closely spaced and not connected by concavity; mesosoma with sparse foveolae; promesonotum with additional sparse, thin, and transverse rugulae and smooth to indistinctly foveolate interspaces on dorsum; gaster smooth with base indistinctly shagreened; body yellow. Minor workers. Head foveolate, foveolae sparse; scape, when laid back, exceeding the posterior head margin by one-third of its length; promesonotum low and moderately long; promesonotal groove absent; propodeal spines minute, triangular; mesosoma foveolate; katepisternum with large, smooth notch; dorsal side of promesonotum and lateral sides of pronotum with reduced sculpture and smooth notches on medial parts; body yellowish brown.
Etymology. Malagasy for river in reference to the Sandrangato River located in the type locality.
Biology. The species was collected between 125-725 m in elevation, in rainforest. Nests were located in rotten logs and sticks on the ground.
Comments. Pheidole renirano sp. nov. is known from several localities in the Toamasina prefecture. Its range covers the area from Réserve Spéciale Ambatovaky north to Antanambe. Morphologically it is most similar to parapatric P. tsaravoniana sp. nov., known from the vicinity of Tsaravoniana in Toamasina. Major workers of P. renirano sp. nov. can be distinguished from majors of P. tsaravoniana sp. nov. based on bright yellow body colouration and promesonotal dorsum with short, transverse rugae with smooth to indistinctly foveolae interspaces; minors can be separated based on yellowish brown body, and reduced sculpture and smooth notches on medial parts of dorsal side of promesonotum and lateral sides of pronotum.  -14.43686, 49.74291;alt. 1350 m;12 Feb 2018;.; montane rainforest, ex rotten log; BLF41097 (CASC).
Diagnosis. Moderately large species. Major workers. Head in full-face view sub-oval, widening posteriorly, with anterior and posterior sides convex, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with dense, short, suberect pilosity; anterior and medial parts of frons with moderately dense, thick, and longitudinal rugae sometimes interrupted in the posteromedial part, interspaces with sparse and distinct rugulae; posterolateral sides with longitudinal to irregular and thick rugae with distinctly rugulate interspaces; area posterolateral from eyes without smooth notches; scape, when laid back, exceeding the midlength of head by approximately one-fifth of its length; inner hypostomal teeth distinct, moderate, closely spaced, triangular, with rounded apex and wide base; outer hypostomal teeth lobe-like, wider than inner hypostomal teeth and approximately the same height, apex directed outward; inner and outer hypostomal teeth closely spaced and connected by indistinct concavity; mesosoma with fine rugofoveolae, dorsal and lateral sides of pronotum with additional transverse and thin rugae and smooth notches; gaster smooth; body brownish orange. Minor workers. Head foveolate with additional indistinct longitudinal rugulae on medial frons, area posterolateral from eyes smooth; scape, when laid back, surpassing the posterior head margin by one-fifth of its length; promesonotum moderately high and long, arched; promesonotal groove present; propodeal spines indistinct, triangular; mesosoma smooth and shiny, only promesonotal dorsum with arched rugae and indistinct foveolae, mesonotum and lateral sides of propodeum with indistinct and sparse foveolae; body yellowish brown.
Etymology. From the type locality. Biology. The species was collected at 1350 m in elevation, in montane rainforest. Nests were located in rotten logs and root mat.

Pheidole sikorae
Diagnosis. Moderately large species. Major workers. Head in full-face view sub-oval, widening posteriorly, with anterior and posterior sides convex, in lateral view sub-oval; ventral and dorsal faces convex; impressed and smooth concavity placed lateral to antennal socket and tentorial pit present; sides of the head with dense, long, suberect to erect pilosity; anterior and medial parts of frons with sparse, thick, longitudinal, and sometimes interrupted rugae and smooth to indistinctly rugulae interspaces; posterolateral sides with more irregular rugae and smooth to indistinctly rugulate interspaces, area posterolateral from eyes without smooth notches; scape, when laid back, exceeding the midlength of head by approximately one-third of its length; inner hypostomal teeth distinct, moderately high, closely spaced, triangular, with rounded apex and wide base; outer hypostomal teeth lobe-like, wider and higher than inner hypostomal teeth, apex directed outward; inner and outer hypostomal teeth closely spaced and connected by concavity; promesonotum predominantly smooth, with sparse, thin to thick, transverse rugae on pronotum and sometimes with fine, irregular rugulae on anepisternum and katepisternum; propodeum with fine, sparse, and indistinct rugulae; gaster smooth; body yellow to orange. Minor workers. Head sculpture variable, from smooth with foveolae restricted to anterior or medial frons to foveolate with smooth patches on vertex and area posterolateral from eyes; foveolae always sparse, frons sometimes with additional, sparse, and irregular rugae; scape, when laid back, surpassing the posterior head margin by one-fifth of its length; promesonotum moderately high and short; promesonotal groove present; propodeal spines very small and triangular; mesosoma smooth and shiny, only dorsum with few transverse, thick rugulae and propodeum with indistinct and sparse foveolae; body yellow to orange.  Head. In full-face view sub-oval, widening posteriorly, with anterior and posterior sides convex (Fig. 53B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth invisible. Sides of the head with dense, long, suberect to erect pilosity; whole head with relatively dense, long, decumbent to erect pilosity. Anterior and medial parts of frons with sparse and thick, longitudinal, and sometimes interrupted rugae and smooth to indistinctly rugulate interspaces; posterolateral sides with more irregular rugae and smooth to indistinctly rugulate interspaces. Impressed and smooth concavity placed lateral to antennal socket and tentorial pit present. Occipital lobes with thick, sparse, irregular rugae, sometimes fading medially, interspaces smooth or with fine, indistinct rugulae. Gena with sparse, thick, and longitudinal rugae and smooth interspaces. Area posterolateral from eyes with weaker and sparser rugoreticulae. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, wide, and shallow; median longitudinal carina absent; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by approximately one-third of its length; pilosity decumbent to suberect (Fig. 53B, D). Inner hypostomal teeth distinct, moderately high, closely spaced, triangular, with rounded apex and wide base; outer hypostomal teeth lobe-like, wider and higher than inner hypostomal teeth, apex directed outward; inner and outer hypostomal teeth closely spaced and connected by concavity (Fig. 64K). Mesosoma. In lateral view, promesonotum short, angular, and moderately high, posterior mesonotum moderately steep, mesonotal process indistinct, tubercle-like; promesonotal groove absent; metanotal groove present; propodeal spines moderate, triangular, thin, with acute apex; humeral area laterally weakly produced (Fig. 53D). Surface shiny, promesonotum predominantly smooth, with sparse, thin to thick, transverse rugae on pronotum and sometimes with fine, irregular rugulae on anepisternum and katepisternum; propodeum with fine, sparse, and indistinct rugulae. Pilosity sparse, long, and erect (Fig. 53D, F). Petiole. Shiny with fine and sparse rugulae; peduncle; node smooth to indistinctly rugulose, low, triangular, with rounded apex, in rear view node dorsoventrally convex; pilosity moderately sparse and erect (Fig. 53D, F). Postpetiole. Shiny, with fine and sparse rugulae; in dorsal view postpetiole oval, lateral margins medially with two dentate projections; pilosity long, moderately sparse, and erect (Fig. 53D, F). Gaster. Shiny and smooth; pilosity sparse, long, and erect (Fig. 53D, F). Colour. Yellow to orange; gaster usually slightly darker (Fig. 53D, F). Head. Cephalic margin straight or indistinctly convex (Fig. 53A). Pilosity moderately dense, long, and erect. Head sculpture variable, from smooth with foveolae restricted to anterior or medial frons to foveolate with smooth patches on vertex and area posterolateral from eyes; foveolae always sparse, frons sometimes with additional, sparse, and irregular rugae; antennal sockets with few thick, curved outward rugae and smooth to foveolae interspaces. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, surpassing the posterior head margin by one-fifth of its length; pilosity dense, suberect to erect (Fig. 53A, C). Mesosoma. In lateral view, promesonotum moderately high, short, arched; promesonotal groove present, sometimes indistinct; metanotal groove present and distinct; propodeal spines very small and triangular, apex acute (Fig. 53C). Sculpture smooth and shiny, only dorsum with few transverse, thick rugulae and propodeum with indistinct and sparse foveolae. Pilosity sparse, moderately long, and erect (Fig. 53C, E). Petiole. Peduncle short and thin with ventral face slightly convex (Fig. 53C, E). Postpetiole. Short, low, and convex; with few short, erect setae (Fig. 53C, E). Gaster. With sparse, erect pilosity (Fig. 53C, E). Colour. Orange to yellow (Fig. 53C, E).
Biology. The species was collected between 20-1580 m in elevation, in montane and littoral rainforest. Nests were located in rotten logs, dead twigs above ground, under moss, and rot pockets above ground.
Comments. Major workers of Pheidole sikorae can be easily separated from all other Malagasy Pheidole based on strongly reduced sculpture of mesosoma and presence of impressed and smooth concavity placed lateral to antennal socket and tentorial pit. However, minor workers of P. sikorae have highly variable head sculpture. In most cases the head is predominantly smooth with sparse foveolae restricted to anterior and medial frons, but sometimes sparse foveolae extend to the whole frons and smooth patches are present only on vertex and area posterolateral from eyes. Minors of P. sikorae with strongly developed head sculpture are indistinguishable from minor workers of P. antranohofa sp. nov., a species known from Parc National de Marojejy in Antsiranana. Distribution ranges of these taxa do not overlap.  (CASC).
Diagnosis. Moderately large species. Major workers. Head in full-face view suboval, not widening posteriorly, with anterior and posterior sides convex, slightly narrowing posteriorly, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with dense, moderately long, suberect to erect pilosity; medial part of frons with thick, moderately sparse, longitudinal and interrupted rugae, posteromedial part with rugae more irregular and slightly directed outward, interspaces smooth to finely foveolate; anterolateral sides with thick, moderately dense, and longitudinally irregular rugae, posterolateral sides with rugae more irregular, interspaces with dense and distinct foveolae; occipital lobes and area posterolateral from eyes without smooth notches; scape, when laid back, exceeding the midlength of head by two-fifths of its length; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed slightly inward; outer hypostomal teeth lobe-like, slightly wider than and approximately the same height as inner hypostomal teeth, apex directed slightly outward; inner and outer hypostomal teeth closely spaced and not connected by concavity; mesosoma with fine rugofoveolae; pronotal dorsum with reduced sculpture and additional thin, interrupted, and transverse rugae; lateral sides of pronotum and katepisternum with smooth notches; gaster smooth; body ferruginous. Minor workers. Head sculpture variable; predominantly smooth or foveolae sparse and fading on medial frons and area posterolateral from eyes; vertex with sparse and short rugulae; frons with very sparse, short, and irregular rugae; area posterolateral from eyes with reduced sculpture or predominantly smooth; scape, when laid back, surpassing the posterior head margin by one-fifth of its length; promesonotum moderately high and short, arched; promesonotal groove present; propodeal spines small and triangular; mesosoma with sparse rugofoveolae; promesonotal dorsum and katepisternum with smooth notches or smooth; pronotum with additional sparse, short, and transverse rugulae; body brown.
Description  Head. In full-face view sub-oval, not widening posteriorly, with anterior and posterior sides convex, slightly narrowing posteriorly (Fig. 54B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with dense, moderately long, suberect to erect pilosity; whole head with dense, long, decum-bent to erect pilosity. Medial part of frons with thick, moderately sparse, longitudinal, and interrupted rugae, posteromedial part with rugae more irregular and slightly directed outward, interspaces smooth to finely foveolate; anterolateral sides with thick moderately dense and longitudinally irregular rugae, posterolateral sides with rugae more irregular, interspaces with dense and distinct foveolae. Occipital lobes with thick, irregular rugae and rugofoveolate interspaces. Area posterolateral from eyes rugoreticulate to rugofoveolate, sometimes with additional longitudinal to irregular, thick rugae. Gena with relatively dense and thick, longitudinal rugae and rugoreticulate interspaces. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina absent; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by two-fifths of its length; pilosity subdecumbent to erect (Fig. 54B, D). Inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed slightly inward; outer hypostomal teeth lobe-like, slightly wider than and approximately the same height as inner hypostomal teeth, apex directed slightly outward; inner and outer hypostomal teeth closely spaced and not connected by concavity (Fig. 64L). Mesosoma. In lateral view, promesonotum short, angular, and moderately low, posterior mesonotum moderately steep, mesonotal process indistinct, tubercle-like; promesonotal groove absent; metanotal groove absent; propodeal spines moderately short, with moderately wide base and acute apex; humeral area laterally weakly produced (Fig.  54D). Surface shiny with fine rugofoveolae; pronotal dorsum with reduced sculpture and additional thin, interrupted, and transverse rugae; lateral sides of pronotum and katepisternum with smooth notches. Pilosity moderately dense, long, and erect (Fig.  54D, F). Petiole. Shiny with fine foveolae; node smooth to finely foveolate, low, triangular, with rounded and thin apex, in rear view node dorsoventrally straight to slightly convex; pilosity moderately sparse and erect (Fig. 54D, F). Postpetiole. Shiny and foveolate; dorsum with reduced sculpture and smooth notch; in dorsal view oval, lateral margins medially with two dentate projections; pilosity long, moderately sparse and erect (Fig. 54D, F). Gaster. Shiny and smooth; pilosity dense, long, and erect ( Fig.  54D, F). Colour. Ferruginous; legs, gaster, and antennae bright brown (Fig. 54D, F). Head. Cephalic margin indistinctly concave or straight (Fig. 54A). Pilosity relatively dense, long, decumbent to suberect. Sculpture shiny and variable; predominantly smooth or foveolate with foveolae sparse and fading on medial frons and area posterolateral from eyes; vertex with sparse and short rugulae; frons with very sparse, short, and irregular rugae; area posterolateral from eyes with reduced sculpture or predominantly smooth; antennal sockets with few thick, curved outward rugae and smooth to indistinctly foveolate interspaces. Clypeus with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, surpassing the posterior head margin by one-fifth of its length; pilosity dense, subdecumbent to erect (Fig. 54A,  C). Mesosoma. In lateral view, promesonotum moderately high and short, arched; promesonotal groove indistinct; metanotal groove distinct; propodeal spines small and triangular (Fig. 54C). Sculpture shiny with sparse rugofoveolae; promesonotal dorsum and katepisternum with smooth notches or smooth; pronotum with additional sparse, short, and transverse rugulae. Pilosity moderately sparse, long, and erect (Fig. 54C,  E). Gaster. With sparse, erect pilosity (Fig. 54C, E). Colour. Brown, legs and antenna yellowish brown (Fig. 54C, E).
Etymology. From the type locality. Biology. The species was collected between 390-1657 m in elevation, in rainforest, montane rainforest, montane ravine forest, and in urban areas. Nests were located in rotten logs, rotten sticks on the ground, and in soil.
Comments. Pheidole sofia sp. nov. is a widespread species known from Ambositra in Fianarantsoa north to Joffreville in Antsiranana. The species is most similar to parapatric P. manantenina sp. nov., known from Parc National de Marojejy in Antsiranana. Major workers of P. sofia sp. nov. differ from P. manantenina sp. nov. in medial part of frons with interspaces finely foveolate, lateral sides of frons with more longitudinally irregular rugae, body ferruginous, and promesonotum never with reduced sculpture; minor workers can be separated based on more distinct sculpture on head, and mesosoma with sparse rugofoveolae, promesonotal dorsum and katepisternum with smooth notches or smooth, and presence of additional sparse, short, and transverse rugulae on pronotum.  (CASC).
Diagnosis. Moderately large species. Major workers. Head in full-face view suboval, not widening posteriorly, with anterior and posterior sides relatively straight, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with dense, moderately long, suberect to erect pilosity; medial part of frons with moderately sparse, thick, longitudinal, and interrupted rugae, rugae in posteromedial slightly directed outward, interspaces shiny with sparse and indistinct rugofoveolae; anterolateral sides with longitudinal, thick, and relatively sparse rugae; posterolateral sides with irregular, thick, and relatively sparse rugae; interspaces shiny with sparse and indistinct rugofoveolae; occipital lobes and area posterolateral from eyes without smooth notches; scape, when laid back, exceeding the midlength of head by two-fifths of its length; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, approximately the same height and width as inner hypostomal teeth, apex directed outward; inner and outer hypostomal teeth closely spaced and not connected by concavity; promesonotum predominantly smooth, with indistinct rugofoveolae on lateral sides; katepisternum rugofoveolate with smooth notch; propodeum rugofoveolate; gaster smooth; body dark orange. Minor workers. Head foveolate; medial part of frons with smooth notch and indistinct, short rugulae; area posterolateral from eyes predominantly smooth; scape, when laid back, surpassing the posterior head margin by one-fifth of its length; promesonotum moderately low and moderately long, arched; promesonotal groove absent; propodeal spines small and triangular; pronotum with very indistinct and sparse foveolae; mesonotum, anepisternum, katepisternum, and propodeum smooth; body dark yellow.
Description Head. In full-face view sub-oval, not widening posteriorly, with anterior and posterior sides relatively straight (Fig. 55B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with dense, moderately long, erect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with moderately sparse, thick, longitudinal, and interrupted rugae, posteromedial rugae slightly directed outward, interspaces shiny with sparse and indistinct rugofoveolae; anterolateral sides with longitudinal, thick, and relatively sparse rugae; posterolateral sides with irregular, thick, and relatively sparse rugae; interspaces shiny with sparse and indistinct rugofoveolae. Occipital lobes with sparse, thick, and irregular rugae; interspaces smooth. Gena with relatively sparse, thick, and longitudinal rugae and smooth interspaces. Area posterolateral from eyes with thin and dense rugofoveolae and smooth interspaces. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina absent; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by two-fifths of its length; pilosity subdecumbent to erect (Fig. 55B,  D). Inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, approximately the same height and width as inner hypostomal teeth, apex directed outward; inner and outer hypostomal teeth closely spaced and not connected by concavity (Fig. 64M). Mesosoma. In lateral view, promesonotum short, angular, and moderately low, posterior mesonotum moderately steep, mesonotal process indistinct, tubercle-like; promesonotal groove absent; metanotal groove indistinct; propodeal spines moderately long, moderately nar- row, with acute apex; humeral area laterally weakly produced (Fig. 55D). Surface shiny; promesonotum predominantly smooth, with indistinct rugofoveolae on lateral sides; katepisternum rugofoveolae with smooth notch; propodeum rugofoveolate. Pilosity relatively dense, long, and erect (Fig. 55D, F). Petiole. Shiny with fine and sparse rugofoveolae; node smooth, low, triangular, with rounded and thin apex, in rear view node dorsoventrally slightly convex; pilosity moderately sparse and erect (Fig. 55D, F).
Etymology. Latin for sparse in reference to sparse rugae on the frons. Biology. The species was collected at 1606 m in elevation, in montane rainforest. Nests were located in rotten logs.
Comments. Pheidole sparsa sp. nov., described from Bemanevika in Mahajanga, is most similar to P. dasos sp. nov., known from Makirovana forest in Antsiranana, and P. hazo sp. nov., recorded so far only from the vicinity of Andranoma in Antananarivo. Majors of P. sparsa sp. nov. can be distinguished from both taxa mentioned above by medial part of frons with moderately sparse rugae, interspaces with sparse and indistinct rugofoveolae, and predominantly smooth promesonotum with indistinct rugofoveolae on lateral sides; minors of P. sparsa sp. nov. can be distinguished from P. hazo sp. nov. by dark yellow body colouration and propodeum with indistinct and sparse foveolae, and from P. dasos sp. nov. by dark yellow body colouration, shorter scape surpassing the posterior head margin by one-fifth of its length, and pronotum with very indistinct and sparse foveolae.  (CASC). Paratype. • 1w.; same data as for holotype, CASENT0923285 (CASC).
Diagnosis. Moderately large species. Major workers. Head in full-face view suboval and not widening posteriorly, with anterior and posterior sides slightly convex, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with thick, interrupted, dense, and longitudinal rugae with smooth to indistinctly rugulate interspaces; occipital lobes predominantly smooth, only anterior part with indistinct longitudinal rugae; denser and thinner longitudinal rugae with rugulate interspaces; area posterolateral from eyes with reduced sculpture and predominantly smooth; scape, when laid back, exceeding the midlength of head by approximately two-fifths of its length; inner hypostomal teeth distinct, distinct, moderately large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, narrower than and approximately as high as inner teeth, apex directed outward; inner and outer hypostomal teeth closely spaced and not connected by concavity; mesosoma rugofoveolate; pronotum with sparse foveolae, its dorsum with smooth notch; katepisternum with large, smooth notch; body brown. Minor workers. Head foveolate; median frons with short and indistinct longitudinal rugulae; vertex with fading sculpture; area posterolateral from eyes smooth; scape, when laid back, exceeding the posterior head margin by one-third of its length; promesonotum low and moderately long; promesonotal groove present; propodeal spines small and triangular; mesosoma foveolate; body bright brown.
Etymology. Malagasy for summit in reference to the type locality located close to the mountain peak.
Biology. The species was collected at 2100 m in elevation, in montane shrubland. Nest was located under rootmat on stone.
Comments. Pheidole tampony sp. nov. is a member of a group of species characterised by distinctly reduced head sculpture in major workers with occipital lobes entirely or predominantly smooth, area posterolateral from eyes partially or entirely smooth and shiny or with reduced sculpture and smooth notches. The group consists of four species: P. litigiosa, P. masoandro sp. nov., P. gracilis sp. nov., and P. tampony sp. nov. Pheidole tampony sp. nov. is known only from Parc National de Marojejy in Antsiranana and its distribution does not overlap with other members of this group. Both minor and major workers of this species can be easily separated from other members of this group based on darker, bright brown to brown body colouration. However, major workers of P. tampony sp. nov. can be confused with majors of sympatric P. manantenina sp. nov. Pheidole tampony sp. nov. can be separated based on presence of distinct smooth notch on posteriormost part of area posterolateral from eyes and partially smooth occipital lobes (P. manantenina sp. nov. has posteriormost part of area posterolateral from eyes and occipital lobes with sparse and reduced sculpture that are never smooth), lower promesonotum with more distinctly developed mesonotal process (P. manantenina sp. nov. has promesonotum higher and lacking mesonotal process), and smooth notch on katepisternum (P. manantenina sp. nov. has katepisternum entirely sculptured). Both taxa distinctly differ in minor workers: P. tampony sp. nov. has mi- Head. In full-face view sub-oval, slightly widening posteriorly, with anterior and posterior sides convex (Fig. 57B). In lateral view sub-oval; ventral and dorsal faces convex; inner hypostomal teeth visible. Sides of the head with very dense, long, suberect to erect pilosity; whole head with dense, long, decumbent to erect pilosity. Medial part of frons with thick, interrupted, dense, and longitudinally irregular rugae with indistinctly to distinctly rugulate interspaces; lateral sides of frons with denser, thick, and irregular rugae, interspaces with dense and distinct rugulae. Occipital lobes with irregular and sparser rugae and indistinctly rugulate to smooth interspaces. Area posterolateral from eyes with dense, thick, longitudinal rugae with distinctly rugulate interspaces, sculpture fading posteriorly. Gena with relatively sparse, thick, and longitudinal rugae and indistinctly rugulate interspaces. Centre of clypeus smooth and shiny, lateral sides with indistinct rugulae; median notch present, moderately wide, and shallow; median longitudinal carina present; lateral longitudinal carinae absent. Scape, when laid back, exceeding the midlength of head by one-fifth of its length; pilosity subdecumbent to erect (Fig. 57B, D). Inner hypostomal teeth distinct, large, and wide, closely spaced, triangular with apex directed slightly inward; outer hypostomal teeth lobe-like, narrower than and approximately as high as inner teeth, apex directed upward; inner and outer hypostomal teeth closely spaced and not connected by concavity (Fig. 64O). Mesosoma. In lateral view, promesonotum short, angular, and moderately low, posterior mesonotum moderately steep, mesonotal process indistinct, tubercle-like; promesonotal groove absent; metanotal groove present; propodeal spines moderately long, relatively wide, and with acute apex; humeral area weakly produced (Fig. 57D). Surface shiny and rugofoveolate; katepisternum with reduced sculpture and sometimes with smooth notch. Pilosity moderately dense, long, and erect (Fig. 57D, F). Petiole. Shiny with sparse foveolae; node finely foveolate to smooth, triangular, with rounded and thick apex, in rear view node dorsoventrally slightly convex; pilosity moderately sparse and erect (Fig. 57D, F). Postpetiole. Shiny and foveolate; dorsum with reduced sculpture; in dorsal view oval, lateral margins medially with two small and dentate projections; pilosity long, moderately sparse, and erect (Fig. 57D, F). Gaster. Shiny with slightly shagreened base; pilosity moderately dense, long, and erect (Fig. 57D, F). Colour. Yellow to blackish brown, antenna and legs yellowish (Fig. 57D, F). Head. Cephalic margin slightly convex (Fig. 57A). Pilosity relatively sparse, short, subdecumbent. Sculpture shiny and foveolate; median frons with short, indistinct and irregular rugulae; antennal sockets with few indistinct, curved outward rugae and foveolate interspaces. Clypeus foveolate; with median longitudinal carina absent; two lateral longitudinal carinae absent. Scape, when laid back, exceeding the posterior head margin by two-fifths of its length; pilosity dense, subdecumbent to erect (Fig. 57A, C). Mesosoma. In lateral view, promesonotum low and moderately long, arched; prome-sonotal groove indistinct; metanotal groove distinct; propodeal spines minute and triangular (Fig. 57C). Sculpture shiny and foveolate; katepisternum with sparser foveolae. Pilosity sparse, moderately long, and erect (Fig. 57C, E). Gaster. With sparse, erect pilosity (Fig. 57C, E). Colour. Yellow to black, legs and antenna yellowish (Fig. 57C, E). Etymology.
Greek for hairy in reference to dense setosity on lateral sides of head in major workers.
Biology. The species was collected between 74-1657 m in elevation, in montane rainforest and in gardens. Nests were located in rotten logs, rotten tree stumps, and dead twigs above ground.
Comments. Pheidole trichotos sp. nov. can be grouped with species characterised by dark body colouration, ranging in major workers from brownish black to black and in minor workers from black to dark brown, with body entirely foveolate. The group consists of three sympatric species: P. alina sp. nov., P. trichotos sp. nov., and P. mainty sp. nov. Pheidole alina sp. nov. and P. mainty sp. nov. are known from the northernmost part of the island. Major workers of P. trichotos sp. nov. differ from P. alina sp. nov. and P. mainty sp. nov. in medial part of frons with thick, interrupted, dense, and longitudinally irregular rugae with indistinctly to distinctly rugulate interspaces and shagreened base of first gastral tergite. Minor workers of P. trichotos sp. nov. differ from P. alina sp. nov. in smaller body size and brighter body colouration; from P. mainty sp. nov. in entirely foveolate head and mesosoma. Majors of P. trichotos sp. nov. can be also confused with major workers of parapatric P. veteratrix and sympatric P. anomala sp. nov. P. trichotos sp. nov. can be separated from both of those taxa based on shagreened base of first gastral tergite and darker body colouration.  (CASC). Paratype. • 1w.; same data as for holotype, CASENT0923286 (CASC).
Diagnosis. Moderately large species. Major workers. Head in full-face view suboval, not widening posteriorly, with anterior and posterior sides slightly convex, in lateral view sub-oval; ventral and dorsal faces convex; sides of the head with moderately dense, moderately long, suberect pilosity; medial part of frons with thick, interrupted, dense, and longitudinal rugae with distinctly rugulate interspaces; lateral sides of frons with dense, thick, and longitudinally irregular rugae, interspaces with dense rugulae; occipital lobes and area posterolateral from eyes without smooth notches; scape, when laid back, exceeding the midlength of head by two-fifths of its length; inner hypostomal teeth distinct, moderately large, closely spaced, triangular, with rounded apex directed inward; outer hypostomal teeth lobe-like, wider than and approximately as high as inner teeth, apex directed upward; inner and outer hypostomal teeth closely spaced and connected by indistinct concavity; mesosoma rugofoveolate; pronotum with additional thin, moderately dense, and transverse rugae; gaster smooth with base indistinctly shagreened; body ferruginous. Minor workers. Head foveolate, foveolae sparse; scape, when laid back, exceeding the posterior head margin by one-third of its length; promesonotum low and moderately long; promesonotal groove absent; propodeal spines minute and triangular; mesosoma foveolate; katepisternum with large smooth notch; dorsal side of promesonotum and lateral sides of pronotum with reduced sculpture and smooth notches on medial parts; body yellowish brown.
Etymology. From the type locality. Biology. The species was collected at 1036 m in elevation, in rainforest. Nest was located in rotten log.
Comments. Pheidole tsaravoniana sp. nov. is described from the vicinity of Tsaravoniana in Toamasina and is parapatric with P. renirano sp. nov. from several localities distributed in the Toamasina prefecture (from Réserve Spéciale Ambatovaky north to Antanambe). Both taxa have very similar morphology. Major workers of P. tsaravoniana can be distinguished from majors of P. renirano sp. nov. based on ferruginous body colouration and promesonotal dorsum with transverse and more irregular rugae with distinctly rugofoveolae interspaces; minors can be separated based on brown body, never reduced sculpture, and lack of smooth notches on medial parts of dorsal side of promesonotum and lateral sides of pronotum.
Diagnosis. Moderately large species. Major workers. Head in full-face view oval, not widening posteriorly, with anterior and posterior sides convex, in lateral view suboval, ventral and dorsal faces convex, occipital cleft very shallow; sides of the head with dense, moderately long, suberect pilosity; medial frons with moderately dense, thin, longitudinal to irregular and interrupted rugae, rugae in posteromedial part slightly directed outward, interspaces shiny with sparse and distinct rugofoveolae; occipital lobes and area posterolateral from eyes never smooth; scape, when laid back, exceeding the midlength of head by two-fifths of its length; inner hypostomal teeth distinct, large, closely spaced, triangular, with rounded apex directed upward; outer hypostomal teeth lobe-like, wider than inner hypostomal teeth and approximately the same height, apex directed outward; inner and outer hypostomal teeth closely spaced and not connected by concavity; mesosoma with thick and sparse foveolae; lateral sides of pronotum and propodeum with smooth notches; body yellowish brown. Minor workers. Head foveolate; anteromedial part of frons with smooth notch; area posterolateral from eyes predominantly smooth; scape, when laid back, surpassing the posterior head margin by one-fifth of its length; promesonotum moderately high and short; promesonotal groove absent; propodeal spines minute and triangular; mesosoma with thick foveolae; body yellowish brown.
Etymology. Latin for shallow in reference to very shallow occipital cleft. Biology. The species was collected at 1300 m in elevation, in montane rainforest. Nest was located in a dead twig above ground.
Comments. Pheidole vadum sp. nov. is a member of the group of species characterised by major workers with head in full-face view oval and not widening posteriorly and medial part of frons with thick, moderately sparse, irregular rugae or medial frons with moderately dense, thin, longitudinal anteriorly to irregular posteriorly, interrupted rugae and very shallow occipital cleft. Minor workers of this group have a short and moderately high promesonotum and dark body colouration ranging from orange to brown. The group consists of three species: P. vadum sp. nov., P. analavelona sp. nov., and P. ambohimanga sp. nov. Pheidole vadum sp. nov. is known from the vicinity of Antananarivo and is sympatric with P. ambohimanga sp. nov. Its majors can be easily separated from P. ambohimanga sp. nov. based on presence of moderately dense, thin, longitudinal anteriorly to irregular posteriorly, interrupted rugae on medial frons and very shallow occipital cleft; minor workers can be separated based on predominantly foveolate head sculpture lacking additional rugae. Additionally, minors of P. vadum sp. nov. can be confused with workers of other members of the sikorae group, especially with workers of P. sava sp. nov. and P. sparsa sp. nov., both known from the northern part of the island. However, minor workers of P. vadum sp. nov. can be separated based on the combination of the following characters: body yellowish brown, head and mesosoma predominantly foveolate with no additional sculpture, scape, when laid back, surpassing the posterior head margin by one-fifth of its length, promesonotum short and moderately high, and promesonotal groove absent.
Biology. The species was collected between 500-1700 m in elevation, in rainforest, montane rainforest and montane forest. Nests were located in rotten logs, under stones and under moss.
Comments. Pheidole veteratrix express high variability in body colouration and head sculpture in minor workers. Body colouration varies from brown to dark brown with intermediate forms but the type of body colouration is stable within colony. Head sculpture of minor workers is predominantly foveolate, most often with vertex and area posterolateral from eyes partially or entirely smooth, additionally foveolae can be covered by a network of rugae that are longitudinal on frons to transverse of vertex, rugae can be thin to thick, and most of the time interrupted. Dark brown populations can be confused with parapatric P. mainty sp. nov. but its major workers can be easily separated based on lack of shagreened first gastral tergite and body never brownish black; minor workers differ in sparser foveolae on mesosoma and at least partially smooth katepisternum. Populations of P. veteratrix with brighter body colouration are similar to P. anomala sp. nov., a species known from Parc National Montagne d'Ambre in Antsiranana. Major workers of P. veteratrix can be separated based on brown to dark brown body and frons with smooth to indistinctly rugulate interspaces; minor workers based on body colouration which is never yellow and presence of smooth notches on katepisternum. Minors of P. veteratrix also can be confused with minor workers of P. joffreville sp. nov., known from the northernmost part of the Antsiranana prefecture, but they differ in low and long promesonotum, absence of smooth notch on anteromedial frons, and minute propodeal spines.
Pheidole veteratrix angustinoda was distinguished from P. veteratrix based on smaller body size and shape of postpetiole, which according to the description is as wide as long. After study of the type specimens of both taxa and additional investigation of new material, we concluded that those two differences mentioned by Forel (1892) overlap with the intraspecific variability of P. veteratrix. Additionally, we were unable to find any additional characters allowing us to separate those two taxa. Thus, we consider Pheidole veteratrix angustinoda a junior synonym of Pheidole veteratrix.  (CASC). Paratypes. • 9w., 3s.; same data as for holotype; CASENT0491860, CASENT0491863, CASENT0491862, CASENT0491864, CASENT0872247 (CASC, MHNG, PBZT). foveolae can occur on propodeal dorsum and lateral sides of pronotum. Pilosity very sparse, moderately long, and erect (Fig. 61C, E). Postpetiole. Short, low, and relatively flat; with few short, erect setae (Fig. 61C, E). Gaster. With sparse, erect pilosity (Fig.  61C, E). Colour. Brown, legs and antenna yellow (Fig. 61C, E).
Etymology. Malagasy for brown in reference to body colouration. Biology. The species was collected at 1300 m in elevation, in montane rainforest. Nests were located in rotten logs. nantly smooth with transverse rugae on dorsum and indistinct rugofoveolae on lateral sides; katepisternum and anepisternum predominantly smooth; propodeum rugofoveolate. Pilosity relatively dense, long, and erect (Fig. 62D, F). Petiole. Shiny with fine and dense rugofoveolae; node smooth, low, triangular, with rounded and thin apex, in rear view node dorsoventrally slightly convex; pilosity moderately sparse and erect (Fig.  62D, F). Postpetiole. Shiny and smooth; in dorsal view oval, lateral margins medially with two dentate projections; pilosity long, moderately sparse and erect (Fig. 62D, F).
Etymology. Malagasy for yellow in reference to the body colouration. Biology. The species was collected between 600-1100 m in elevation, in rainforest and montane rainforest. Nests were located in rotten logs, root mats, rotten tree stumps, and rotten sticks on the ground.
Comments. Pheidole vony sp. nov. is a member of a group of species characterised by body colouration bright yellow to orange in majors and yellow in minors, head sub-oval, not widening posteriorly with sides not convex or convex indistinctly, and medial part of frons with longitudinal and interrupted rugae on the anterior part and distinctly irregular rugae on the posterior one. The group includes three taxa: P. vony sp. nov., P. befotaka sp. nov., and P. mamiratra sp. nov. Pheidole vony sp. nov. is known from two localities in  Toamasina: Montagne d'Anjanaharibe and Montagne d'Akirindro, and its distribution doesn't overlap with two remaining members of the group. Morphologically P. vony sp. nov. is most similar to P. mamiratra sp. nov., known only from Station Forestière Angavokely in Antananarivo. Major workers of P. vony sp. nov. differ from P. mamiratra sp. nov. in medial part of frons with moderately dense and thin rugae and inner hypostomal teeth large and triangular, with rounded apex directed outward and outer hypostomal teeth lobe-like, lower, and more narrow than inner hypostomal teeth; minors differ in more distinctly foveolate head sculpture. However, minor and major workers of P. vony sp. nov. can be also confused with P. sparsa sp. nov., known from Bemanevika in Ma-hajanga, and P. hazo sp. nov., described from the vicinity of Antananarivo. Majors of P. vony sp. nov. differ from P. sparsa sp. nov. and P. hazo sp. nov. in median frons with thinner and irregular rugae and more irregular sculpture on lateral sides of frons; minor workers differ in smaller propodeal spines, lack of promesonotal groove, strongly reduced sculpture of mesosoma, and head lacking additional, indistinct rugulae.