Taxonomy of the ant genus Carebara Westwood (Formicidae, Myrmicinae) in the Malagasy Region

Abstract The genus Carebara is revised for the Malagasy region, and based on the examination of over 10,000 specimens, twenty-three species are recognized. Twenty one of these are described as new (C. bara sp. n., C. berivelo sp. n., C. betsi sp. n., C. creolei sp. n., C. demeter sp. n., C. dota sp. n., C. hainteny sp. n., C. hiragasy sp. n., C. jajoby sp. n., C. kabosy sp. n., C. lova sp. n., C. mahafaly sp. n., C. malagasy sp. n., C. omasi sp. n., C. placida sp. n., C. raberi sp. n., C. salegi sp. n., C. sampi sp. n., C. tana sp. n., C. tanana sp. n., C. vazimba sp. n.), and two are redescribed, C. grandidieri Forel (= C. voeltzkowi Forel n. syn.) and C. nosindambo Forel. A lectotype is designated for C. nosindambo. C. creolei sp. n. is known only from Mauritius and Seychelles, C. grandidieri Forel is distributed in Comoros, Madagascar and Mayotte, and the other twenty-one species are endemic to Madagascar. Most of the Carebara species recorded in this work are endemic to a specific habitat (ecoregion), but some of them (C. bara sp. n., C. grandidieri Forel, C. jajoby sp. n., C. kabosy sp. n., and C. nosindambo Forel) are widespread within Madagascar across all major habitats. The worker caste of Carebara can be differentiated from other genera in the Myrmicinae subfamily by the presence of the following combination of characters: antennae of eight to eleven segments, with a two-segmented club; anterior clypeal margin without central isolated seta (rarely present in some species or specimens), and usually with four distinct setae; mandibles with four to seven teeth (except in one species from Ghana - C. crigensis with three teeth); and palp formula 2,2 or 1,2. We report that almost all Carebara species found in the Malagasy region have intermediates (distinct forms) in the major worker subcaste, with the largest major workers showing remnants of queen flight sclerites and ocelli. The widespread presence of intermediates in the major worker subcaste expands the morphological boundaries of Carebara. We present an overview of the natural history of Carebara in the Malagasy region, an illustrated key for the identification of the known Malagasy species of Carebara, as well as high-resolution images and distribution maps. Unique identifiers are used for all specimens studied, including type material, and the raw data that forms the basis of this study are available on www.antweb.org (open access).


Introduction
The Malagasy region includes the island of Madagascar, as well as the smaller islands of the western Indian Ocean (Comoros, Mauritius, Mayotte, Reunion, Seychelles, and others). The greatest concentration of biodiversity and endemism in the region is found in Madagascar (Goodman and Benstead 2003). Ants in particular have been well studied and systematically collected in the Malagasy region since 1992. These collections were made across the Malagasy region using a variety of different standardized methods (see Fisher 2005), resulting in the identification of many new species and genera. As of September 2017, there are approximately 656 species of ants described from the Malagasy region, nearly half of which have been described since 2000 (Bolton 2017). The total ant fauna in the Malagasy region is estimated to be greater than 1200 species.
The genus Carebara is distributed worldwide, present mainly in tropical and subtropical regions, and contains approximately 253 described taxa (222 valid species, including the newly described species in this work, 23 valid subspecies, and 8 fossil species) (Bolton 2017;Fischer et al. 2014Fischer et al. , 2015Bharti and Kumar 2013). The taxonomy and limits of Carebara have not been well defined, although several genera were recently synonymized with Carebara based on morphological and molecular information, for example : Fernández (2004: Fernández ( , 2006: Fernández ( and 2010 placed Afroxyidris, Oligomyrmex, Paedalgus and Parvimyrma as junior synonyms of Carebara, and indicated similarities between C. villiersi and Pheidologeton, expanding the boundaries of the genus. Fischer et al. (2014) placed Pheidologeton as a junior synonym of Carebara, based on the morphological similarities between former Pheidologeton and the C. polita group, (C. brevipilosa, C. madibai, C. perpusilla, C. polita, C. nicotianae, C. silvestrii, C. urichi, and C. villiersi), and the prescence of intermediates (distinct forms) in the major worker subcaste of the C. polita group. In addition to the morphological similarities, molecular studies have revealed a close relationship between Carebara, Oligomyrmex and Pheidologeton (Moreau et al. 2006;Moreau and Bell 2013), and a recent molecular study provided additional support for the synonymization of Pheidologeton under Carebara, revealing that the former is nested within the latter (Ward et al. 2015). The Carebara taxa included in the Ward et al. (2015) study included: C. affinis (formerly Pheidologeton), C. urichi (C. polita group), C. alperti (morphologically similar to former Pheidologeton), C. nosindambo (formerly Oligomyrmex) and C. vidua (Carebara s. str.); no samples of for-mer Paedalgus were included in this work. Future studies including morphological and molecular data and sampling including former Paedalgus taxa will help to understand the evolutionary biology of this group, as well as the monophyly of Carebara. After all of the recent synonymizations were made, Carebara species (not including former Pheidologeton) were provisionally placed in five species groups: C. concinna (Oligomyrmex and Carebara s. str.), C. alperti (alperti group), C. crigensis (Afroxyidris), C. escherichi (Paedalgus), and C. polita groups (Fernández 2004, Bharti and Kumar 2013, Fischer et al. 2014, former Pheidologeton species were not included in any species groups yet, but in future revisions could be splitted in two species groups (Fischer et al. 2014). Fischer et al. (2014Fischer et al. ( , 2015 highlighted the need to revise all Carebara species to better delimit the boundaries of the species groups proposed by Fernández (2004) and Bharti and Kumar (2013). A preliminary morphological study suggests that all Carebara species can be placed in ten species groups (Azorsa et al. in preparation); future molecular, morphological and biogeographic studies will help to clarify and better understand the taxonomy of Carebara and their limits. Before this work only three species of Carebara were reported from Madagascar: C. grandidieri (Forel, 1891) (q, m), C. nosindambo (Forel, 1891) (w, m, q), and C. voeltzkowi (Forel, 1907) (q). We describe 21 new species and propose C. voeltzkowi as a junior synonym of C. grandidieri, increasing the diversity of Carebara to 23 species for the Malagasy region.

Samples
This project is based on the study of more than 10,000 specimens collected from 1992 to 2016. Collecting methods included more than 6,000 leaf litter samples, 4,000 pitfall traps, and 9,000 additional hand collecting events (for more information see Fisher 2005). All the material studied in this work is deposited in the Entomology Collection of the California Academy of Sciences, San Francisco CA, U.S.A. We also examined type material of the three described species of Carebara (C. grandidieri, C. nosindambo and C. voeltzkowi syn. n. of C. grandidieri), deposited in the Muséum d'Histoire Naturelle de la Ville de Genève, Geneva, Switzerland, and the Museum of Natural History, Humboldt University, Berlin. Additional specimens were revised from the P. S. Ward Collection, University of California, Davis CA, U.S.A., and the Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts, U.S.A.

Images
We present high-resolution images from all species and type material examined, holotype images from all the new species, lectotype images of C. nosindambo (queen), as well as images of the queen of C. voeltzkowi (syn. n. of C. grandidieri). We also present images of the intermediates of each species. All images were created using a JVC KY-F75 digital camera and Syncroscopy Auto-Montage (version 5.0) software. Images of all species were edited using Adobe Illustrator and Photoshop, and uploaded to Ant-Web, where anyone can access and download the images of all the species presented in this work (www.antweb.org). The illustrations showing the measurements and morphological characters used in this work were made using Adobe Illustrator. All imaged specimens (type and non-type material) are uniquely identified with specimen-level codes (e.g. CASENT0483010).

Distribution maps
We mapped the distribution of all species using ArcGIS v10.2.1 (ESRI, Redlands, CA) and R (R Core Team 2017).

Measurements and indices
We measured more than 500 specimens (at least 10 specimens per caste/species, and more in the species with intermediates in the major worker subcaste). Values are presented in mm, with measurements of holotype specimens in parentheses. All measurements were taken with a Leica MZ 12.5 equipped with an orthogonal pair of micrometers at a magnification of 100×.
The following terminology and abbreviations are used ( Figure 1).

HL
Head length: maximum length of head in full-face view between lines drawn across anterior margin of clypeus and lines drawn across the posterolateral corners of head.

HW
Head width: width of head directly behind the eyes (if present) measured in full-face view.

SL
Scape length: maximum scape length excluding basal condyle and neck.

ML
Mandible length: the straight-line length of the mandible at full closure from the mandibular apex to the clypeal margin.

EL
Eye length: maximum diameter of compound eye measured in oblique profile view.

EM
Eye to mandible: distance from base of compound eye to the mandibular insertion, measured in profile view. HD Head depth: maximum depth of head in profile view measured perpendicular to full-face view plane.

Petiole
The petiole varies greatly in shape and combined with pilosity and form of the posterodorsal corner of the propodeum, is one of the most useful characters for differentiating species in Carebara. In profile view, the main variations present among species are: a) ventral face: medially flat, convex or slightly concave; b) dorsum: convex, angulate, rounded, or almost flat; and c) combined outline of dorsal surface of peduncle and anterior face of node, and posterior face of petiolar node: concave or straight.

Mesosoma
In profile view, a) promesonotum: rounded, convex, slightly convex to nearly flat; b) metanotal groove: present, deeply or weakly impressed; c) dorsum of propodeum: flat, concave, slightly concave, convex or slightly convex; d) posterodorsal corner of propodeum: armed or unarmed, rounded, convex, angulate, or with a pair of triangular teeth; e) declivity of propodeum: flat, concave, or slightly concave; f ) propodeal lobe: rounded, convex or triangular; g) propodeal spiracle: rounded, oval, closer to midheight and mid-length of lateropropodeum in larger major workers, distance from posterior border of spiracle to declivity varies between species. In dorsal view, g) dorsum of propodeum: smooth and shiny or sculptured.

Intermediates
The presence of intermediates (major workers with distinct forms, larger major workers with flight sclerites or ocelli) in the major worker subcaste has been reported previously for C. bruchi (formerly Oligomyrmex), C. diversa (formerly Pheidologeton) (Kusnezov, 1951), C. corniger (Ettershank, 1966), C. coeca, C. tenua, and C. coqueta (Fernández 2004(Fernández , 2006. In this work, we report that most Carebara species from the Malagasy region present a complex variation in the major worker subcaste (some species with four distinct forms, with the largest major worker morphologically similar to queens). Larger major workers can be thus considered intercastes, because of their similarities to queens (Peeters 1991). The presence of intermediates is similar to that reported for the C. polita species group (Fischer et al. 2014), further supporting the synonymization of Pheidologeton under Carebara. The ant genera Carebara, Oligomyrmex, and Pheidologeton, where separated mainly because they were monomorphic, dimorphic and polymorphic, respectively, but recent discoveries show that Carebara present a complex morphological variation, so this character was not longer useful to split those genera.
In addition to the variation in the major worker caste, a recent study showed that some Carebara species from the Old World, including C. elmenteitae, C. butteli, C. lilith, C. nayana, and C. phragmotica, possess major workers with phragmotic heads (Fischer et al. 2015). However, despite all of the intensive collections carried out in the Malagasy region, none of the Malagasy Carebara species has been found to have major workers with phragmotic heads. The discoveries reported by Fischer et al. (2014Fischer et al. ( , 2015, and in this work, indicate that the use of standardized methods to collect ants (see Fisher 2005) may help to discover other Carebara species with intermediates or with phragmotic heads in the major worker caste. Future studies could help to better understand the evolution of caste intergradations (Baroni Urbani and Passera 1996, Ward 1997, Molet et al. 2012. Most Carebara species from the Malagasy Region show a remarkable range of morphological diversity, and this is especially noticeable in the major worker subcaste. In some cases, like C. jajoby sp. n., and C. nosindambo Forel, there are four recognizable "intermediates" in the major worker subcaste (from the smallest, intermediate 1, to the largest, intermediate 4) in the same colony (Figures 44,53). Morphologically these intermediates are mosaics between major workers and queens. Intermediates are reported for the following Malagasy species: C. bara sp. n., C. grandidieri Forel, C. jajoby sp. n., C. kabosy sp. n., C. lova sp. n., C. malagasy sp. n., C. nosindambo Forel, C. omasi sp. n., C. placida sp. n., C. raberi sp. n., C. sampi sp. n., and C. vazimba sp. n. The main variations present in the intermediates from the smallest to the largest are: a) posterolateral corners of head: moderately to strongly expanding posteriorly; b) posterior margin of head: weakly to strongly concave; c) size of the eyes: in some species from one to 75 ommatidia; d) number of ocelli: from one to three; e) form of the mesosoma: showing remnants of queen flight sclerites; f ) propodeal spiracle: distance of propodeal spiracle to declivity of propodeum closer to midlength of propodeal sclerite in larger intermediates; g) hair abundance; and h) sculpture: weakly to strongly sculptured. For the species with intermediates, we did not present a separate description for each intermediate form, but instead only a general discussion of all the forms present in the species. All the variations present in the intermediates were included in the identification key, and can be separated using the major worker key. In some cases, larger intermediates are similar in the form of the head, but they differ in the form of the propodeum, petiole, as well as in the pilosity, so the user should check all characters mentioned on each part of the key.

Biology
Carebara characteristically have both very small minor workers and extremely large major workers. The genus contains one of the smallest ants in the world (minor worker of Neotropical C. minuta has a head width of 0.21 mm, and total length near 1 mm, while in the Malagasy region the smallest Carebara species is the minor worker of C. creolei sp.n. with a head width of 0.26 mm and a total length near 1.2 mm). The largest major worker in the genus Carebara (major worker of C. diversus -formerly Pheidologeton) can reach a total length of 16 mm, while in the Malagasy region the largest Carebara is the major worker of C. jajoby sp.n. with a total length of 4.53 mm (Figures 2, 44). Workers may be monomorphic, dimorphic or polymorphic. Polymorphism is more noticeable in the major worker caste, with some species having four sizes of major workers (e.g. C. jajoby sp. n. and C. nosindambo). We did not report any major worker smaller than the minor worker, but this phenomenon may occur in other species of Carebara (Baroni Urbani 1998). The main differences in the morphology of these intermediates include: size differences in the head, posterolateral corners of head, and thorax; larger major workers with one to three ocelli (ocelli are reduced compared to the queen caste); reduced flight sclerites; and eye size differences. It is possible that the intermediates in the major worker caste are trophic specialists like the intermediates of the ant genus Crematogaster (see Peeters et al. 2013). Colonies can be large, e.g. colonies of C. overbecki and C. urichi contain up to 1000 individuals (minor and major workers), with the proportion of major workers approaching ten percent (Moffett 1986;Wilson 1962). Minor workers nurse the brood, and major workers defend the nest. The diet of Carebara includes mites, entomobryid collembolans and arthropod eggs (Wilson 1962(Wilson , 1986, and according to Fischer (2012), six Carebara species from Kenya (Kakamega forest) have specialized predatory diets.

Distribution
The ant genus Carebara is distributed worldwide, present mainly in tropical and subtropical regions, with approximately 253 described taxa (230 species and 23 subspecies), and the Indomalaya region seems to have more species of Carebara than the other biogeographic regions: 71 species and 14 subspecies (Bolton, 2017). Before this work only three species were recorded for the Malagasy region; these records were reported in the provinces of Fianarantsoa (C. nosindambo), Antananarivo (C. grandidieri) and Toamasina (C. voeltzkowi). Since 1992 and using a variety of standardized methods for ant collections, ants were collected across all Malagasy region (see Fisher, 2005), and based on the revision of specimens collected since 1992, we report 23 species. Carebara was recorded in almost every habitat in the Malagasy region where an ant collection was made ( Figure 3). Most of the Carebara species recorded in this work are endemic to a specific habitat (ecoregion): for example, C. creolei sp. n. is known only from Mauritius and Seychelles, C. grandidieri Forel, which is widely distributed in Madagascar, is also present in Comoros and Mayotte. The other Carebara species are restricted to Madagascar. Five of them are confined to a specific province, ecoregion or habitat: C. berivelo sp. n., C. betsi sp. n., C. mahafaly sp. n., C. malagasy sp. n., and C. vazimba sp. n. Six species are known only from their type locality (C. demeter sp. n., C. placida sp. n., C. raberi sp. n., C. salegi sp. n., C. tana sp. n., C. tanana sp.n.). Six species were collected in more than one province or habitat: C. dota sp. n., C. hainteny sp. n., C. hiragasy sp. n., C. lova sp. n., C. omasi sp. n., C. sampi sp. n., while other five species are widespread and were collected across all major habitats of Madagascar: C. bara sp. n., C. grandidieri Forel, C. jajoby sp. n., C. kabosy sp. n., and C. nosindambo Forel (Figures 68,69). Three species were collected only above 1000 m (C. demeter sp. n., and C. omasi sp. n., and C. tanana sp.n.), seven species were recorded below 600 m (C. berivelo sp. n., C. creolei sp. n., C. lova sp. n., C. 3 Posterodorsal corner of propodeum angulate or convex, without a triangular tooth, or armed with at least a dentiform angle (Fig. 5A  In full-face view, mandible with six teeth; in profile, combined outline of dorsal surface of peduncle and anterior face of node medially concave; anterodorsal corner of node more broadly rounded, petiole node longer (PNL 0.12-0.15); petiole and postpetiole with all hairs suberect to subdecumbent (Fig. 7C); dorsum of propodeum with more than ten long erect to suberect hairs . In full-face view, dorsum of head with well defined longitudinal rugae laterally, and smooth and shiny middle area; in profile gaster with abundant long suberect hairs; distance from propodeal spiracle to declivity less or same as the diameter of the spiracle (Fig. 7A)  In full-face view, dorsum of head smooth and shiny or with fine longitudinal rugae laterally, smooth and shiny frons; in profile gaster with short decumbent to subdecumbent hairs and long subdecumbent to suberect hairs; distance from propodeal spiracle to declivity same or greater than the diameter of the spiracle (Fig. 7B)

15
In full-face view, posterolateral corners of head with a small triangular, toothlike horn; dorsum of head longitudinally rugose laterally, becoming rugoreticulate medially, with a strong median longitudinal ruga reaching almost to the posterior margin of the head (Fig. 13A)  Posterodorsal corner of propodeum with a laminate triangular tooth that is slightly longer than the maximum propodeal spiracle diameter (PSL 0.08-0.09); propodeal spiracle oval and separated by almost twice the diameter of the spiracle from the propodeal declivity (Fig. 15A) .................. C. mahafaly -Posterodorsal corner of propodeum with a triangular tooth that is shorter than the propodeal spiracle diameter (PSL 0.05); propodeal spiracle round and separated by less than half the diameter of the spiracle from the propodeal declivity (Fig. 15B)

18
In full face-view, dorsum of head smooth and shiny, or with fine longitudinal rugae laterally, extending from frontal lobes to midlenght of head, but never reaching to apices of frontal carinae and smooth and shiny frons (

19
In profile, propodeal dorsum flat and slopes at about 30 degrees compared to the ventral margin of the metapleura, gaster with abundant short decumbent hairs; in dorsal view, anterior margin of pronotum sculptured, weakly areolate (Fig. 16E)  In full face-view, posterolateral corners of head narrowed posteriorly ( Fig.  16 A); propodeal tooth triangular and barely longer than propodeal spiracle, distance from posterior border of propodeal spiracle to declivity less than two times the diameter of the spiracle; combined outline of dorsal surface of peduncle and anterior face of node weakly concave (Fig. 17A) ........C. sampi -In full-face view, posterolateral corners of head not as narrowed as above (Fig.  16C); propodeal tooth triangular and short, rarely longer than propodeal spiracle, distance from posterior border of propodeal spiracle to declivity same as or less than the diameter of the spiracle; combined outline of dorsal surface of peduncle and anterior face of node concave medially (Fig. 17B) ......... C. lova

21
In profile, propodeal tooh triangular, well defined, and longer than the diameter of the propodeal spiracle; narrow petiolar peduncle, anterodorsal face of petiolar node weakly convex or straight; in full-face view head usually heart shaped, posterolateral corners of head narrowed anteriorly, head weakly narrowed anteriorly (Fig. 18A, D)

22
In profile, petiolar peduncle tapering evenly from the node toward its anterior articulation, appearing slender anteriorly, dorsal margin of peduncle curving evenly into anterior margin of node, anterodorsal margin of petiole convex; propodeal lobes short and weakly convex, propodeal tooth shorter than propodeal spiracle diameter (Fig. 19A)  In profile, petiolar peduncle not tapering, remaining deep almost to the anterior articulation and here narrowing abruptly, junction of dorsal margin of peduncle and anterior margin of node distinctly inflected, anterodorsal margin of petiole rounded; propodeal lobes short and weakly triangular, propodeal tooth slightly longer than propodeal spiracle diameter (Fig. 19B) .... C. kabosy  3 Head and mesosoma with abundant erect and suberect, long and short hairs, more than 25 hairs on posterior margin of head, and more than 32 hairs on dorsal face of mesosoma; in profile, posterodorsal corner of propodeum convex and unarmed; petiolar node thick, petiole and postpetiole with abundant erect and suberect hairs (Fig. 21B Head and mesosoma with few decumbent to erect, long and short hairs, with fewer than 20 hairs on posterior margin of head, and fewer than 25 hairs on dorsal face of mesosoma; in profile, posterodorsal corner of propodeum armed with at least a dentiform angle or with a distinct triangular tooth, or if propodeum convex and unarmed then with less than 6 long erect hairs on mesosoma; petiole and postpetiole with few subdecumbent to apressed hairs (Fig. 21A)

5
In profile, posterodorsal corner of propodeum evenly convex and unarmed, without trace of a prominent dentiform angle or tooth (Fig. 23A)  In profile, posterodorsal corner of propodeum at least with a dentiform angle, more usually the corner with a pair of small, low, angulate teeth ( Fig. 23B

7
In profile, combined outline of dorsal surface of peduncle and anterior face of node weakly concave, and outline of dorsal surface of propodeum weakly concave (Fig. 24B)  In profile, combined outline of dorsal surface of peduncle and anterior face of node nearly straight; gaster with short appressed hairs, and without longer decumbent, suberect or erect hairs; propodeal teeth acutely triangular and slightly longer than propodeal spiracle diameter; petiolar node smooth and shiny (Fig. 26A)

13
Hairs of the scape, posterior margin and lateral margins of head, abundant and subdecumbent; dorsum of promesonotum with abundant short suberect hairs (20-30 hairs); distance from center of the propodeal spiracle to declivity same or slightly longer than the diameter of the spiracle (Fig. 27A) ........... C. salegi -Hairs of the scape, posterior margin and lateral margins of head, decumbent or appressed; dorsum of promesonotum with short subdecumbent to suberect hairs (fewer than 20 hairs); distance from center of the propodeal spiracle to declivity less than the diameter of the spiracle ( 14 Dorsum of propodeum weakly convex; posterodorsal corner with a pair of very short triangular teeth, length less than propodeal spiracle diameter (Fig.  28A)  Gaster with short decumbent to subdecumbent hairs and long subdecumbent to suberect hairs, lateropropodeum almost smooth and shiny (Fig. 28D) ..18 -Gaster with short appressed to decumbent hairs and long subdecumbent hairs, lateropropodeum sculptured (Fig. 28F)  Gaster with short subdecumbent to decumbent hairs, and more than ten longer subdecumbent or suberect hairs; distance from propodeal spiracle to declivity less than the diameter of the spiracle (Fig. 28H)  Ventral face of petiole medially convex, propodeal spiracle round and small; distance from propodeal spiracle to declivity same as the diameter of the spiracle (Fig. 30B) (Fisher, Griswold et al.) with collection code BLF04511, (CASC: CASENT0077891). Diagnosis. Antennae ten-segmented. Major: Head nearly rectangular, longer than wide, head longitudinally rugose laterally, weakly reticulate near posterior margin of head, frons smooth and shiny, posterior margin of head medially concave, posterolateral corners rounded; posterodorsal corner of propodeum angulate, never with a pair of triangular teeth; dorsum of propodeum nearly flat; combined outline of dorsal surface of peduncle and anterior face of node nearly straight, dorsum rounded; gaster with sparse, long subdecumbent hairs and abundant, short decumbent hairs. Minor: Head longer than wide; posterodorsal corners of propodeum each armed with a weakly developed angular tooth, dorsum of propodeum slightly convex and declining posteriorly; combined outline of dorsal surface of peduncle and anterior face of node nearly straight, posterior margin convex, dorsum rounded; gaster covered by abundant decumbent to subdecumbent hairs, and with sparse and slightly longer subdecumbent hairs.
Head longer than wide (CI 71-79), in full-face view nearly rectangular, about 1.5 times longer than wide. Posterior margin of head medially concave, posterolateral corners rounded, lateral margins straight to weakly convex. Mandibles with five teeth. Anterior margin of clypeus medially concave and laterally convex. Frons without median ocellus. Antennae with ten segments. Scapes short  not surpassing cephalic midlength. Eyes present, consisting of one to three ommatidia (EL 0.01-0.03). Supraclypeal area well defined and triangular.
In profile, posterolateral corner of head with (larger major workers) or without (smaller major workers) a small, obtuse tooth resembling a horn. Promesonotum high and convex, metanotal groove deep. Propodeum about 1.5 times higher than long, dorsal face of propodeum flat or weakly concave, declining posteriorly, propodeum unarmed, posterodorsal corners of propodeum convex or angulate, declivity of propodeum flat to slightly concave in direction of propodeal lobe. Propodeal lobes triangular with blunt apices. Propodeal spiracle rounded and situated above mid-height of sclerite and beyond mid-length of sclerite, by about the diameter of the spiracle; distance from propodeal spiracle to posterodorsal corner of propodeum almost twice the diameter of the spiracle, (PSL 0.04-0.07) and distance to declivity same as the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin and sides rounded; sides of propodeum convex.
Petiole approximately as high as long (PTH 0.14-0.20, PTL 0.15-0.24) and with a short peduncle, ventral face medially convex. Anterodorsal and posterodorsal faces of petiolar node sloping, combined outline of dorsal surface of peduncle and anterior face of node flat, posterior face of node vertical, straight to slightly convex, dorsum rounded. Subpetiolar process slightly shorter than the diameter of the propodeal spiracle. Postpetiolar node rounded and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PPW 0.16-0.23, PTW 0.12-0.17), petiolar node wider than long (PTW 0.12-0.17, PNL 0.08-0.11), anterior and posterior margins of petiole and postpetiole nearly straight, sides rounded in petiole and postpetiole.
Dorsal surface of mandibles, clypeus and frons smooth and shiny, with scattered piligerous punctae on head and mandibles. Dorsolateral faces of head longitudinally rugose, gena with well-developed longitudinal reticulations, weakly marked rugae on frontal lobes, reticulate-rugose sculpture near posterior margin of head. In profile, posterolateral portion of cephalic dorsum smooth and shiny. Mesosoma smooth and shiny, except for katepisternum and propodeal lobe (areolate-rugose), and metapleuron (areolate and with longitudinal rugae). Petiole and ventral face of postpetiole areolate-rugose. In dorsal view, mesosoma, petiole, postpetiole and gaster smooth and shiny.
Lateral margins, and posterolateral corners of head with short subdecumbent hairs, and longer suberect hairs. Scapes with appressed hairs. Outer margin of mandibles with short subdecumbent hairs. Mesosoma with short and long suberect hairs. Petiole, postpetiole and gaster with short decumbent hairs and sparse and slightly longer subdecumbent hairs. Tibia with short appressed hairs. Color yellowish ferruginous, antennae, legs and parts of gaster, slightly lighter.
In profile view, promesonotum weakly convex, metanotal groove slightly impressed. Propodeum about 1.5 times higher than long, dorsal face convex and declining posteriorly, posterodorsal corners of propodeum each armed with a small angulate tooth, declivity of propodeum slightly concave. Propodeal lobes triangular. Propodeal spiracle rounded and situated slightly above mid-height of sclerite by about half the diameter of the spiracle, and beyond mid-length of the sclerite by about the diameter of the spiracle; distance from propodeal spiracle to posterodorsal corner of propodeum same as the diameter of the spiracle (PSL 0.02-0.04), and distance to declivity less than the diameter of the spiracle. In dorsal view, promesonotum longer than wide, anterior margin rounded, sides convex; sides of propodeum weakly convex.
Petiole slightly longer than high (PTL 0.11-0.12, PTH 0.09-0.10) with a short peduncle, ventral face weakly convex in the middle. Combined outline of dorsal surface of peduncle and anterior face of node nearly straight, posterior margin slightly convex, dorsum rounded. Subpetiolar process small, almost the same as the diameter of the propodeal spiracle. Postpetiolar node convex and lower than petiolar node. In dorsal view, postpetiolar node slightly wider than petiolar node (PPW 0.09-0.12, PTW 0.08-0.0.9), petiolar node wider than long (PTW 0.09-0.12, PNL 0.06-0.07), anterior margin of petiole convex, posterior margin slightly concave, anterior and posterior margin of postpetiole nearly straight, sides moderately convex in petiole and postpetiole.
Dorsal surface of mandibles, clypeus and frons smooth and shiny, with abundant piligerous punctae on mandibles and head. Head with fine and short longitudinal ru-gae on malar space and frontal lobes. Mesosoma smooth and shiny, except for katepisternum, below mid-height of metapleuron, and propodeal lobe, which are areolaterugose. Sides of petiole, and ventral face of postpetiole areolate-rugose. In dorsal view, mesosoma, petiole, postpetiole and gaster smooth and shiny.
Lateral margins, scapes and posterior margin of head with subdecumbent hairs. Hairs in the posterior margin shorter than others. Outer margin of mandible with decumbent hairs. Mesosoma with suberect hairs. Petiole, postpetiole, tibia and gaster with short decumbent to subdecumbent hairs, and with sparse and slightly longer subdecumbent hairs. Tibia with abundant to sparse decumbent hairs. Color yellowish ferruginous.
Distribution and biology. Carebara bara is an endemic and widespread species, found across Madagascar (Figure 68), mainly in the tropical dry forest in western Madagascar and the desert spiny bush thicket in the southwest. In the center of Madagascar (montane forest) there is only one record. C. bara occurs in the dry forest, gallery forest, littoral rainforest, montane rainforest, spiny forest/dry forest transition, spiny forest/thicket, spiny thicket, spiny thicket gallery forest transition, and tropical dry forest, and has been collected at elevations ranging from 10-1410 m. Individuals and nest series were collected from rotten logs, in the leaf litter, in leaf mold, and rotten wood.
Comments. Carebara bara can be confused with C. berivelo but can be separated by the form of the propodeum. C. berivelo is armed with a pair of small triangular teeth while C. bara is unarmed in major workers and armed with a small angulate tooth in minor workers. This species can also be confused with C. tana, but in C. tana the combined outline of dorsal surface of peduncle and anterior face of node is medially concave. C. bara is widespread throughout most of Madagascar, with only one record in the center of the island and no records in the east, while C. berivelo and C. tana are restricted to the north of Madagascar. These three species occur in sympatry in the north of Madagascar, other four species were recorded at the same localities: C. grandidieri, C. kabosy, C. malagasy, and C. salegi, which can be separated from C. bara by the characters described above.
C. bara have three intermediates in the major worker subcaste ( Figure 32) with only minor variations between them. The shape of the posterolateral corner of the head and the posterior margin of the head do not vary much. Intermediate 3 has an increase in the size of the eyes, but only one ommatidium. Ocelli are absent in intermediates 1 and 2, and sometimes present in intermediate 3 (one ocellus). Intermediate 3 has reduced flight sclerites. In addition, the dorsum of the mesosoma of intermediate 3 is anteriorly convex and gradually slopes to a declivity. By comparison, in intermediates 1 and 2 the dorsum of the mesosoma is anteriorly convex, and the propodeum is below the promesonotum, which is flat and declining posteriorly to a declivity. Pilosity is nearly identical in all intermediates. The longitudinal rugae of the head are more finely marked in intermediate 1. The sculpture of the mesosoma, petiole and postpetiole is nearly identical in all the intermediates.
Diagnosis. Antennae ten-segmented. Major: Head subrectangular, posterior margin medially concave, and posterolateral corners rounded; promesonotum flat in profile view, quite similar to C. bara, but the propodeum of C. berivelo has a pair of acute teeth, dorsum of propodeum is flat; combined outline of dorsal surface of peduncle and anterior face of node slightly medially concave, anterodorsal corner convex, posterior face of node vertical and nearly straight, dorsum slightly convex. Minor: Head slightly longer than wide, posterior margin nearly straight; promesonotum weakly convex, similar to C. bara but easily differentiated by the presence of a pair of small acute teeth on the propodeum, anterodorsal corner moderately convex, dorsum flat and declining posteriorly; gaster with decumbent hairs. Head longer than wide (CI 73-77), in full-face view nearly subrectangular, about 1.3 times longer than wide. Posterior margin of head medially concave, posterolateral corners rounded, lateral margins nearly straight. Mandibles with five teeth. Anterior margin of clypeus slightly concave medially and laterally convex. Antennae with ten segments. Scapes short (HL 0.56-0.71, SL 0.24-0.27, SI 37-43) not surpassing cephalic midlength. Eyes present, consisting of three ommatidia (EL 0.02-0.04). Supraclypeal area as a triangular depression but poorly defined.
In profile, posterolateral corner of head with (larger major workers) or without (smaller major workers) a small, obtuse tooth resembling a horn. Promesonotum high and convex, metanotal groove present. Propodeum about 1.4 times higher than long, dorsal face of propodeum flat, declining posteriorly, posterodorsal corner of propodeum with a pair of short, triangular teeth, declivity of propodeum flat to slightly concave with thin lateral laminae connecting propodeal lobe. Propodeal lobes triangular with blunt apices. Propodeal spiracle rounded and situated slightly above mid-height of sclerite, and beyond mid-length of sclerite, by about half the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum more than twice but less than three times the diameter of the spiracle (PSL 0.06-0.09), and distance to declivity same as the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin and sides rounded; sides of propodeum nearly straight.
Petiole longer than high (PTH 0.13-0.17, PTL 0.16-0.25) with a relatively short peduncle, ventral face nearly flat but slightly convex in the middle. Combined outline of dorsal surface of peduncle and anterior face of node medially concave, posterior margin nearly vertical and slightly convex, anterodorsal corner convex, and posterodorsal corner rounded, dorsum rounded. Subpetiolar process small, acutely produced, and at about the same as the diameter of the propodeal spiracle. Postpetiolar node rounded and lower than petiolar node. In dorsal view, postpetiolar node slightly wider than petiolar node (PPW 0.16-0.23, PTW 0.12-0.17), petiolar node wider than long (PTW 0.12-0.17, PNL 0.07-0.11), anterior and posterior margins of petiole nearly straight, anterior margin of postpetiole concave and posterior margin straight, sides rounded in petiole and postpetiole.
Dorsal surface of mandibles, clypeus and frons smooth and shiny, with scattered piligerous punctae on head and mandibles. Dorsolateral faces of head with fine longitudinal rugae, reticulate-rugose sculpture near posterior margin of head, gena with longitudinal carinae, weakly marked rugae on frontal lobes. In profile, posterolateral portion of cephalic dorsum smooth and shiny. Sides of pronotum with fine longitudinal and parallel striations, smooth and shiny medially and dorsally, anepisternum smooth and shiny, katepisternum, metapleuron, propodeum, propodeal lobes, petiole and ventral face of postpetiole areolate-rugose. In dorsal view, promesonotum smooth and shiny except for anterior margin which is weakly areolate, propodeum, declivity and petiole areolate-rugose, postpetiole and gaster smooth and shiny.
Lateral margins and posterior margin of head with suberect hairs, and sparse short decumbent hairs. Scapes with appressed hairs. Outer margin of mandible with sparse decumbent hairs. Mesosoma with suberect hairs. Petiole, postpetiole and gaster with short decumbent hairs and sparse long suberect hairs. Tibia with sparse appressed hairs. Color yellowish ferruginous, antennae, legs and parts of gaster, slightly lighter. Head longer than wide (CI 84-92), in full-face view weakly subrectangular, about 1.2 times longer than wide, and slightly narrowed anteriorly. Posterior margin of head slightly concave in the middle, posterolateral corners convex, lateral margins convex. Mandibles with five teeth. Anterior margin of clypeus more or less straight, sides with small, angulate, forwardly directed teeth. Antennae with ten segments. Scape fails to reach the posterior margin of head . Eyes present, consisting of one ommatidium (EL 0.01-0.02). Supraclypeal area triangular but poorly defined and appears as a small oblong depression.
In profile view, promesonotum weakly convex, metanotal groove deeply impressed. Propodeum about 1.45 times higher than long, dorsal face nearly flat and declining posteriorly, anterodorsal corner convex, posterodorsal corners each armed with a triangular tooth, declivity of propodeum concave and with thin lateral laminae. Propodeal lobes triangular. Propodeal spiracle rounded and situated slightly above mid-height of sclerite by about half the diameter of the spiracle, and beyond mid-length of sclerite by about 1.5 times the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum barely larger than the diameter of the spiracle (PSL 0.04-0.05), and distance to declivity less than half the diameter of the spiracle. In dorsal view, promesonotum longer than wide, anterior margin weakly convex, sides convex and narrowed posteriorly; propodeum about as long as wide, sides convex.
Petiole approximately as high as long (PTH 0.09-0.10, PTL 0.11-0.13) with a short peduncle, ventral face convex in the middle. Combined outline of dorsal surface of peduncle and anterior face of node nearly straight, sometimes weakly concave, posterior margin slightly convex, dorsum weakly convex. Subpetiolar process reduced to a small convexity. Postpetiolar node strongly convex and slightly lower than petiolar node, postpetiolar ventral process present, small and convex. In dorsal view, postpetiolar node wider than petiolar node (PPW 0.09-0.11, PTW 0.08), petiolar node wider than long (PTW 0.08, PNL 0.06-0.07), anterior and posterior margins of petiole nearly straight, anterior margin of postpetiole concave and posterior margin nearly straight, sides of petiole slightly convex and sides of postpetiole strongly convex.
Lateral margins and posterior margin of head with subdecumbent hairs. Scapes with abundant decumbent hairs. Outer margin of mandible with decumbent and appressed hairs. Mesosoma with suberect hairs. Petiole, postpetiole, and gaster with subdecumbent to decumbent hairs, and some longer and subdecumbent hairs. Tibia with appressed hairs. Color yellowish ferruginous.
Distribution and biology. Carebara berivelo is known only from the north of Madagascar and was found in littoral rainforest and tropical dry forest ( Figure 68). The specimens were found at three elevations: 90 m, 180 m, and 325 m. C. berivelo was collected using maxi-Winkler and pitfall traps. Individuals and colonies were found in sifted litter, leaf mold, and rotten wood.
In profile view, promesonotum high and convex, metanotal groove deeply impressed. Propodeum about 1.6 times higher than long, dorsal face of propodeum flat, declining posteriorly, propodeum armed, posterodorsal corners each armed with a small triangular tooth, anterodorsal corners angulate, declivity of propodeum concave with thin lateral laminae. Propodeal lobes short and convex. Propodeal spiracle rounded and situated above mid-height of sclerite, and beyond mid-length of sclerite, by about the diameter of the spiracle; distance from propodeal spiracle to posterodorsal corner of propodeum almost three times the diameter of the spiracle (PSL 0.05-0.08), and distance to declivity almost the same as the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin and sides rounded; sides of propodeum weakly convex.
Petiole slightly longer than high (PTH 0.15-0.19, PTL 0.19-0.22) with short peduncle, ventral face medially convex. Combined outline of dorsal surface of peduncle and anterior face of node flat, posterior face of node vertical and slightly concave, dorsum weakly rounded, anterodorsal corner convex, and posterodorsal corner weakly rounded. Petiolar node slightly narrowed at its dorsum. Subpetiolar process small, weakly triangular, and shorter than the diameter of the propodeal spiracle, at about half the diameter of the spirale. Postpetiolar node rounded and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PPW 0.17-0.20, PTW 0.13-0.15), petiolar node wider than long (PTW 0.13-0.15, PNL 0.08-0.09), anterior and posterior margins of petiole and postpetiole straight, sides rounded in petiole and strongly convex in postpetiole.
Dorsal surface of mandibles, lower median portion of clypeus and supraclypeal area smooth and shiny, with scattered piligerous punctae on head and mandibles. Head with longitudinal, well-defined rugae, which extend from propodeal lobes and posterior margin of supraclypeal area to posterior margin of head, with a few, weak rugulae on upper median portion of clypeus. In profile, posterolateral portion of cephalic dorsum usually smooth and shiny, sometimes with short longitudinal rugulations. Sides of pronotum smooth and shiny, while mesopleuron, metapleuron, petiole and ventral face of postpetiole are areolate. In dorsal view, promesonotum smooth and shiny medially, as well as postpetiole and gaster, finely areolate on propodeum, petiole and near anterior and posterior margins of promesonotum.
Lateral margins and posterior margin of head with short suberect hairs, scapes with appressed hairs, and outer margin of mandible with decumbent hairs. Mesosoma with short and long suberect hairs. Petiole and postpetiole with subdecumbent hairs, and longer suberect hairs, gaster with abundant subdecumbent hairs. Tibia with abundant subdecumbent and decumbent hairs. Color yellowish ferruginous.
In profile view, promesonotum weakly convex, nearly flat, metanotal groove deeply impressed. Propodeum about 1.5 times higher than long, dorsal face of propodeum nearly flat and declining posteriorly, posterodorsal corners each armed with a small triangular, (sometines angulate), tooth, anterodorsal corner nearly convex and higher than posterodorsal corner of promesonotum, declivity medially concave and with thin lateral laminae. Propodeal lobes triangular. Propodeal spiracle rounded and situated slightly above mid-height of sclerite by about half the diameter of the spiracle, and beyond mid-length of sclerite by about 1.5 times the diameter of the spiracle; distance from propodeal spiracle to posterodorsal corner of propodeum almost twice the diameter of the spiracle (PSL 0.03-0.04), and distance to declivity less than half the diameter of the spiracle. In dorsal view, promesonotum about 1.27 times longer than wide, anterior margin rounded, sides convex; sides of propodeum same as promesonotum.
Petiole slightly longer than high (PTL 0.13-0.14, PTH 0.11-0.12) with a short peduncle, ventral face medially convex. Combined outline of dorsal surface of peduncle and anterior face of node straight to slightly concave medially, posterior face of node vertical and slightly convex, anterodorsal and posterodorsal corners of petiolar node sloping, dorsum narrowed and rounded. Subpetiolar process weakly triangular, and shorter than the diameter of the propodeal spiracle. Postpetiolar node rounded and lower than petiolar node. Postpetiolar ventral process produced as a small triangular denticle. In dorsal view, petiolar node not as wide as postpetiolar node (PTW 0.08-0.10, PPW 0.12-0.13), and petiolar node wider than long (PNL 0.06-0.07, PTW 0.08-0.10), anterior and posterior margin of petiole and postpetiole straight, sides rounded in petiole and convex in postpetiole.
Dorsal surface of mandibles, clypeus and head smooth and shiny, with scattered piligerous punctae on head and mandibles. Gena and frontal lobes with fine linear rugulae. Mesosoma smooth and shiny, except for katepisternum and metapleuron which are areolate. Petiole and ventral face of postpetiole areolate-rugose. In dorsal view, mesosoma, postpetiole and gaster smooth and shiny, declivity and petiole finely areolate.
Lateral margins and posterior margin of head with abundant short subdecumbent hairs. Scapes with abundant decumbent hairs. Outer margin of mandible with appressed hairs. Mesosoma with suberect hairs. Petiole and postpetiole with short decumbent hairs and longer subdecumbent hairs. Tibia with abundant decumbent hairs. Gaster with abundant subdecumbent hairs. Color yellowish ferruginous.
Distribution and biology. Carebara betsi is known only from the center of Madagascar ( Figure 68), in montane rainforest with an elevation of 1410 m, and was collected in sifted litter using Winkler traps on a 50 sample transect. The microhabitats of this species are leaf mold and rotten wood.
Comments. Carebara betsi is endemic to the montane rainforest on the high plateau of Madagascar and can be easily separated from the other species by the following combination of characters: combined outline of dorsal surface of peduncle and anterior face of node flat, and hairs on the gaster abundant and subdecumbent. Also major workers present well-marked longitudinal and parallel rugae. Other seven species are present in this area: C. grandidieri, C. hainteny, C. jajoby, C. kabosy, C. mahafaly, C. nosindambo, and C. omasi, which can be differentiated from C. betsi by the combination of characters mentioned above.

Carebara creolei
In profile view, promesonotum convex, metanotal groove deeply impressed. Propodeum about 1.5 times higher than long, dorsal face of propodeum nearly concave closer to posterodorsal corner, and convex closer anterodorsal corner, propodeum armed, posterodorsal corners each armed with a triangular tooth upwardly directed, declivity of propodeum concave with lamellate lateral margination on each side. Propodeal lobes short and triangular. Propodeal spiracle rounded and situated slightly above mid-height of sclerite, and beyond mid-length of sclerite, by about half the diameter of the spiracle; distance from propodeal spiracle to posterodorsal corner of propodeum almost four times the diameter of the spiracle (PSL 0.06-0.07), and distance to declivity about 1.5 times the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin and sides rounded; sides of propodeum weakly concave in the middle.
Petiole longer than high (PTL 0.15, PTH 0.10-0.11) with relatively long peduncle, ventral face nearly flat but weakly convex medially. Combined outline of dorsal surface of peduncle and anterior face of node deeply concave medially, posterior face of node convex, anterodorsal corner rounded and posterodorsal corner convex, dorsum flat and declining posteriorly. Subpetiolar process produced as a small triangular denticle, slightly larger than propodeal spiracle. Postpetiolar node slightly convex, nearly flat, and lower than petiolar node. In dorsal view, postpetiolar node almost as wide as petiolar node (PTW 0.09-0.11, PPW 0.09-0.11), petiolar node wider than long (PTW 0.09-0.11, PNL 0.07-0.08), anterior and posterior margins of petiole straight, anterior margin of postpetiole straight, posterior margin rounded, sides of petiole rounded, sides of postpetiole convex.
Dorsal surface of mandibles, clypeus and supraclypeal area smooth and shiny, with scattered piligerous punctae on head and mandibles. Clypeus with a few poorly defined transverse rugae. Head reticulate-rugose in full-face view, with irregular longitudinal rugulae which do not reach posterior margin of head. Cephalic dorsum between frontal carinae with two longitudinal rugulae, extending from posterior clypeal margin to posterior quarter of head. In profile, posterolateral portion of cephalic dorsum areolate-rugose, except for smooth and shiny ventral area. Mesosoma areolate-rugose, except for middle sides of pronotum which are smooth and shiny. Petiole and ventral face of postpetiole areolate. In dorsal view, mesosoma areolate, petiole and postpetiole smooth and shiny, with scattered foveolae.
Lateral margins and posterior margin of head with short, sparse decumbent and appressed hairs. Scapes with appressed hairs. Outer margin of mandible with few decumbent hairs. Mesosoma with short decumbent hairs, and sparse long and erect hairs. Petiole, postpetiole and gaster with short decumbent to appressed hairs, and sparse long subdecumbent hairs. Tibia with decumbent hairs. Color yellowish ferruginous. Head a little longer than wide (CI 79-88), in full-face view nearly subquadrate, about 1.1 times longer than wide, narrowed anteriorly. Posterior margin of head nearly straight, posterolateral corners rounded, lateral margins slightly convex. Mandible with five teeth. Anterior margin of clypeus with a concavity flanked by a pair of triangular teeth. Antennae with nine segments. Scapes barely exceeding midpoint of head (HL 0.31-0.33, SL 0.18-0.20, SI 58-63). Eyes present, consisting of one ommatidium (EL 0.01). Supraclypeal area triangular and extends posteriorly toward antennal insertions.
In profile, promesonotum weakly convex, nearly flat, metanotal groove deeply impressed. Propodeum about 1.25 times higher than long, dorsal face of propodeum convex towards anterodorsal corner and medially concave, posterodorsal corners each armed with a triangular tooth, declivity of propodeum concave with lamellate lateral margination on each side. Propodeal lobes short and convex. Propodeal spiracle rounded and situated above mid-height of sclerite, and beyond mid-length of sclerite by about the diameter of the spiracle; distance from propodeal spiracle to posterodorsal corner of propodeum about four times the diameter of the spiracle (PSL 0.05-0.06), and distance to declivity about half the diameter of the spiracle. In dorsal view, promesonotum about 1.08 times longer than wide, anterior margin and sides of promesonotum rounded, sides of propodeum weakly concave near posterodorsal corner.
Petiole longer than high (PTL 0.10-0.11, PTH 0.07-0.09) with a relatively long peduncle, ventral face nearly flat to weakly convex in the middle. Combined outline of dorsal surface of peduncle and anterior face of node deeply concave, posterior face of node slightly convex, anterodorsal corner rounded, posterodorsal corner convex, dorsum flat and declining posteriorly. Subpetiolar process produced as a small denticle, usually the same as the diameter of the propodeal spiracle. Postpetiolar node nearly flat and slightly lower than petiolar node. In dorsal view, petiolar node almost as broad as postpetiolar node (PTW 0.07-0.08, PPW 0.07), petiolar node slightly wider than long (PTW 0.0.7-0.0.8, PNL 0.06), anterior margin of petiole convex, posterior margin straight, anterior margin of postpetiole nearly straight and posterior margin slightly convex, sides of petiole and postpetiole convex to rounded.
Lateral margins and posterior margin of head with short decumbent to appressed hairs. Scapes with abundant decumbent hairs. Outer margin of mandible with a few decumbent hairs. Mesosoma with long suberect hairs, and short subdecumbent hairs. Petiole and postpetiole with short appressed hairs and longer subdecumbent hairs. Tibia with decumbent hairs and gaster with abundant short subdecumbent hairs and sparse longer subdecumbent hairs. Color yellowish ferruginous.
Distribution and biology. Carebara creolei is only known from Mauritius and Seychelles ( Figure 68). It occurs in the coastal scrub, mangrove, mixed forest, and rainforest. The species was collected at different elevations, ranging from 1 m to 200 m, using Winkler traps. The individuals and colonies were found in sifted litter, leaf mold, rotten wood, under coconut husks on the ground, and under rootmats/litter on rocks. The distribution of this species on two distant islands is interesting given the presence of invasive species on these islands. It is possible that C. creolei has been introduced to these islands, but a review of described species from outside the region, notability SE Asia, did not turn up any possible candidates. Until futher evidence is obtained, it is best to consider this species as a new species and native to the region.
Diagnosis. Antennae ten-segmented. Major: Head longer than wide, nearly subrectangular in full-face view, lateral margins straight and parallel, head with longitudinal and irregular rugae, reticulate-rugose close to posterior margin of head; petiole triangular in profile view, combined outline of dorsal surface of peduncle and anterior face of node almost straight, ventral face medially convex, subpetiolar process present. Minor: Head longer than wide, slightly narrowed anteriorly, lateral margins weakly convex; dorsum of promesonotum and anterodorsal corner of propodeum at the same height, posterodorsal corner of propodeum each armed with a small triangular, angulate tooth; combined outline of dorsal surface of peduncle and anterior face of node weakly concave in the middle, posterior face slightly convex; gaster with abundant subdecumbent hairs.
In profile, posterolateral corner of head with (medium and larger major workers) or without (smaller major workers) a small, obtuse tooth resembling a horn. Promesonotum high and strongly convex, metanotal groove deeply impressed. Propodeum about 1.6 times higher than long, dorsal face of propodeum slightly convex, nearly flat, declining posteriorly, posterodorsal corners of propodeum each armed with a small triangular tooth, declivity of propodeum concave, nearly flat, with thin lateral laminae. Propodeal lobes triangular. Propodeal spiracle rounded and situated above mid-height of sclerite by about half the diameter of the spiracle, and beyond mid-length of sclerite by about 1.5 times the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about twice the diameter of the spiracle (PSL 0.04-0.06), and distance to declivity same as the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin and sides rounded; sides of propodeum straight.
Petiole slightly longer than high (PTL 0.17-0.20, PTH 0.14-0.17) with short peduncle, ventral face medially convex. Combined outline of dorsal surface of peduncle and anterior face of node nearly straight, posterior face of node vertical and slightly concave, anterodorsal corner convex, posterodorsal corner rounded, dorsum convex. Subpetiolar process produced as denticle, slightly larger than the diameter of the propodeal spiracle. Postpetiolar node convex and lower than petiolar node. In dorsal view, petiolar node not as wide as postpetiolar node (PTW 0.12-0.14, PPW 0.16-0.18), petiolar node wider than long (PTW 0.12-0.14, PNL 0.08-0.10), anterior and posterior margins of petiole and postpetiole nearly straight, sides rounded in petiole and postpetiole.
Dorsal surface of mandibles, clypeus, supraclypeal area, and median area of head smooth and shiny; scattered piligerous punctae on mandibles and head. Head with longitudinal and irregular rugae and reticulate-rugose near the posterior margin. In profile, posterolateral portion of cephalic dorsum smooth and shiny. Mesosoma smooth and shiny, except for katepisternum (areolate), metapleuron (longitudinally and parallel areolate rugose), and propodeal lobes (areolate-rugose). Petiole and ventral face of postpetiole areolate-rugose. In dorsal view, mesosoma, petiole, postpetiole and gaster smooth and shiny, declivity of propodeum, anterior and posterior face of petiole finely areolate.
Lateral margins and posterior margin of head with short suberect hairs, short appressed hairs below eye level. Scapes with appressed hairs. Outer margin of mandible with decumbent to appressed hairs. Mesosoma with long and short suberect hairs. Petiole and postpetiole with short decumbent hairs and long subdecumbent hairs. Tibia with decumbent hairs. Gaster with abundant decumbent hairs, and longer suberect hairs. Color yellowish ferruginous.
Head longer than wide (CI 85-89), in full-face view nearly subrectangular, about 1.2 times longer than wide, and slightly narrowed anteriorly. Posterior margin of head nearly straight to slightly concave in the middle, posterolateral corners strongly convex, lateral margins slightly convex. Mandibles with five teeth. Anterior margin of clypeus nearly straight medially and laterally convex. Antennae with ten segments. Scape fails to reach the posterior margin of head (HL 0.34-0.37, SL 0.20-0.23, SI 59-64). Eye present, consisting of two ommatidia (EL 0.01). Supraclypeal area almost triangular and not well defined.
In profile view, promesonotum convex, metanotal groove deeply impressed. Propodeum about 1.3 times higher than long, dorsal face of propodeum nearly flat, de-clining posteriorly, anterodorsal corner convex, posterodorsal corners each armed with a small angulate tooth, declivity of propodeum slightly concave with thin lateral laminae which extend from posterodorsal corner of propodeum to propodeal lobe. Propodeal lobes triangular. Propodeal spiracle nearly oval and situated above mid-height of sclerite, and beyond mid-length of sclerite by about the diameter of the spiracle; distance from propodeal spiracle to posterodorsal corner of propodeum about 2.5 times the diameter of the spiracle (PSL 0.02-0.04), and distance to declivity about 1.4 times the diameter of the spiracle. In dorsal view, promesonotum slightly longer than wide (about 1.13 times longer than wide), anterior margin and sides weakly rounded; sides of propodeum weakly convex.
Petiole slightly longer than high (PTL 0.12-0.14, PTH 0.10-0.11) with short peduncle, ventral face medially convex. Combined outline of dorsal surface of peduncle and anterior face of node weakly concave in the middle, posterior face of node vertical and nearly straight, anterodorsal corner convex, posterodorsal corner rounded, dorsum rounded. Subpetiolar process produced as denticle, slightly larger than the diameter of the propodeal spiracle. Postpetiolar node rounded and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PPW 0.11-0.12, PTW 0.08-0.09), petiolar node wider than long (PNL 0.06-0.07, PTW 0.08-0.09), anterior and posterior margins of petiole slightly convex, anterior and posterior margin of postpetiole straight, sides of petiole and postpetiole rounded.
Dorsal surface of head, mandibles and clypeus smooth and shiny, with scattered piligerous punctae on head and mandibles, except in central longitudinal area, malar area with short longitudinal rugae. Mesosoma smooth and shiny, except for katepisternum (areolate), and metapleuron (finely areolate-rugose). Petiole and ventral face of postpetiole areolate. In dorsal view, mesosoma, petiole, postpetiole, and gaster smooth and shiny.
Lateral margins of head with decumbent hairs, posterior margin with short subdecumbent hairs, scapes with abundant subdecumbent hairs. Outer margin of mandibles with decumbent hairs. Mesosoma with short suberect hairs, and long subdecumbent hairs. Petiole and postpetiole with decumbent hairs and longer subdecumbent hairs. Tibia with abundant decumbent hairs. Gaster with abundant, short subdecumbent hairs, and sparse suberect hairs. Color yellowish ferruginous.
Distribution and biology. Carebara demeter is known only from northwestern Madagascar (Figure 68), in montane rainforest with an elevation of 1175 m. It was collected using Winkler traps, and individuals were found in leaf litter, leaf mold and rotten wood.
Comments. Carebara demeter is endemic to the northwest of Madagascar. It can be confused with C. tana due to the form of the head. However, C. demeter has irregular longitudinal rugae and is rugoreticulate near the posterior margin of the head, while the frontal area is smooth and shiny in C. tana. The petiolar node of C. tana is thicker than C. demeter. The anterior margin of the petiole is nearly straight in C. demeter, but slightly concave in C. tana. The anteroventral corner of the petiole has a well-developed triangular tooth in C. demeter, and a small angulate triangular tooth in C. tana. The anterodorsal corner of the petiole is convex in C. tana, but rounded in C. demeter.
The posterodorsal corner is convex in C. demeter, but slightly concave in C. tana. Only two additional species were recorded in this area: C. grandidieri, and C. jajoby.
C. demeter does not have intermediates in the major worker subcaste. Diagnosis. Antennae ten-segmented. Major: Head longer than wide, lateral margins straight, head with longitudinal and parallel rugae, reticulate rugose close to posterolateral corners of head; promesonotum strongly convex, dorsum of propodeum slightly convex, nearly flat, posterodorsal corners with small angulate tooth; combined outline of dorsal surface of peduncle and anterior face of node slightly concave, posterior margin vertical and nearly straight; gaster with subdecumbent hairs. Minor: Head longer than wide, lateral margins slightly convex; propodeum with small, triangular, angulate teeth; combined outline of dorsal surface of peduncle and anterior face of node nearly straight, posterior margin vertical and concave.
In profile, posterolateral corner of head with a small, triangular tooth resembling a horn. Promesonotum high and strongly convex, metanotal groove deeply impressed. Propodeum lower than promesonotum. Propodeum about 1.8 times higher than long, dorsal face of propodeum slightly convex, nearly flat, declining posteriorly, posterodorsal corners each armed with a very small angulate tooth, declivity of propodeum vertical and concave with thin lateral laminae. Propodeal lobes triangular. Propodeal spiracle nearly oval and situated above mid-height of sclerite by about half the diameter of the spiracle, and beyond mid-length of sclerite by about the diameter of the spiracle; distance from propodeal spiracle to posterodorsal corner of propodeum about two times the diameter of the spiracle (PSL 0.05-0.07), and distance to declivity same as the diameter of the spiracle. In dorsal view, promesonotum about as long as wide (1.1 times longer than wide), anterior margin and sides of promesonotum rounded; sides of propodeum weakly convex.
Petiole approximately as high as long (PTH 0.15-0.18, PTL 0.19-0.23) and with a relatively short peduncle, ventral face slightly convex in the middle. Combined outline of dorsal surface of peduncle and anterior face of node concave, posterior face of node vertical and nearly straight, anterodorsal corner convex, posterodorsal corner rounded, dorsum convex. Subpetiolar process produced as a small denticle, almost as large as the diameter of the propodeal spiracle. Postpetiolar node strongly convex and lower than petiolar node. In dorsal view, petiolar node not as broad as postpetiolar node (PTW 0.13-0.16, PPW 0.17-0.22) and petiolar node wider than long (PNL 0.09-0.10, PTW 0.13-0.16), ante-rior and posterior margins of petiole straight, anterior margin of postpetiole concave, posterior margin nearly straight, sides of petiole rounded and strongly convex in postpetiole.
Dorsal surface of mandibles, clypeus and supraclypeal area smooth and shiny, with scattered piligerous punctae on mandibles and head. Head with well defined longitudinal rugae, and reticulate rugose near the posterior margin, gena with longitudinal rugae extending to the posterolateral corners. In profile, posterolateral portion of cephalic dorsum smooth and shiny but with finely longitudinal reticulations. Mesosoma smooth and shiny, except for katepisternum (areolate), and metapleuron (finely areolate and with longitudinal rugae). Petiole and ventral face of postpetiole areolate. In dorsal view mesosoma, petiole, postpetiole and gaster, smooth and shiny except for declivity, anterior face of petiole and postpetiole which are finely areolate.
Lateral margins of head with short subdecumbent hairs, posterolateral corners with scattered suberect hairs. Scapes with appressed hairs. Outer margin of mandibles with short appressed hairs. Mesosoma with short and long suberect hairs, petiole and postpetiole with decumbent hairs and longer subdecumbent hairs. Tibia with decumbent hairs. Gaster with abundant subdecumbent hairs. Color yellowish.
Description Head longer than wide (CI 80-92), in full-face view nearly subquadrate, about 1.1 times longer than wide, weakly narrowed anteriorly. Posterior margin of head slightly concave in the middle, posterolateral corners rounded, lateral margins slightly convex. Mandibles with five teeth. Anterior margin of clypeus medially convex, and laterally angulate. Antennae with ten segments. Scape fails to reach the posterior margin of head (HL 0.38-0.41, SL 0.23-0.25, SI 58-63). Eyes present, consisting of one ommatidium (EL 0.01-0.02). Supraclypeal area triangular and well defined.
In profile view, promesonotum weakly convex, metanotal groove deeply impressed. Propodeum about 1.65 times higher than long, dorsal face of propodeum nearly flat and declining posteriorly, posterodorsal corners of propodeum each armed with a small triangular tooth, anterodorsal corner of propodeum convex, declivity vertical and concave with thin lateral laminae. Propodeal lobes triangular. Propodeal spiracle rounded and situated above mid-height of sclerite by about the diameter of the spiracle, and beyond mid-length of sclerite by about two times the diameter of the spiracle; distance from propodeal spiracle to posterodorsal corner of propodeum almost twice the diameter of the spiracle (PSL 0.03-0.04), and distance to declivity same as the diameter of the spiracle. In dorsal view, promesonotum about as long as wide (1.1 times longer than wide), anterior margin weakly convex, sides convex and narrowed posteriorly; sides of propodeum straight to weakly convex.
Petiole about as high as long (PTL 0.12-0.16, PTH 0.11-0.13) and with a short peduncle, ventral face medially convex. Combined outline of dorsal surface of peduncle and anterior face of node nearly straight, posterior face of node vertical and slightly concave, anterodorsal corner convex, posterodorsal corner rounded, dorsum slightly convex. Subpetiolar process produced as a small denticle, almost as large as the diameter of the propodeal spiracle. Postpetiolar node convex and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PPW 0.12-0.14, PTW 0.09-0.10), petiolar node wider than long (PNL 0.06-0.07, PTW 0.09-0.10), anterior and posterior margin of petiole nearly straight, anterior margin of postpetiole slightly concave, posterior margin convex, sides of petiole convex and rounded in postpetiole.
Dorsal surface of mandibles, median portion of clypeus and supraclypeal area smooth and shiny, with scattered piligerous punctae on head and mandibles, except for smooth and shiny frons; malar area and frontal lobes with longitudinal rugae. Mesosoma smooth and shiny, except for katepisternum (areolate), and metapleuron (weakly areolate and with longitudinal and parallel rugae). Petiole and ventral face of postpetiole areolate. In dorsal view, mesosoma, petiole, postpetiole and gaster smooth and shiny.
Lateral margins of head with subdecumbent hairs, posterior margin of head with suberect hairs. Scapes with abundant decumbent hairs. Outer margin of mandible with decumbent hairs. Mesosoma with short and long suberect hairs. Petiole and postpetiole with short decumbent hairs and longer subdecumbent hairs. Tibia with abundant decumbent hairs. Gaster with abundant subdecumbent hairs, and sparse suberect hairs. Color yellowish ferruginous.
Distribution and biology. Carebara dota is known only from southwestern and north-central Madagascar ( Figure 68). This species was found in habitats such as gallery forest, grassland, littoral rainforest, montane rainforest, montane rainforest edge, and rainforest. C. dota was collected at elevations ranging from 10 m to 1670 m using maxi-Winkler and pitfall traps. Individuals and colonies were found in leaf mold and rotten wood.
Comments. Carebara dota is endemic to Madagascar, and major workers are easily distinguished from other species by the longitudinal and parallel rugae on the dorsal surface of the head. Six species were recorded at the same places were this species was collected: C. bara, C. grandidieri, C. hainteny, C. jajoby, C. nosindambo, and C. sampi, which can be separated from C. dota by the characters mentioned above.
In profile view, promesonotum convex, mesonotum shallowly present and lower than dorsum of promesonotum, metanotal groove present. Propodeum lower than promesonotum, about 1.2 times higher than long, dorsal face of propodeum nearly flat and declining posteriorly, posterodorsal corner angulate to dentate, declivity of propodeum slightly concave with thin lateral laminae in direction of propodeal lobe. Propodeal lobes short and convex. Propodeal spiracle rounded and situated above midheight of sclerite, and beyond mid-length of sclerite by about half the diameter of the spiracle; distance from propodeal spiracle to posterodorsal corner of propodeum about 2.5 times the diameter of the spiracle (PSL 0.05-0.09), and distance to declivity almost twice the diameter of the spiracle. In dorsal view, promesonotum about 1.2 times longer than wide, anterior margin of promesonotum rounded, sides convex and narrowed posteriorly; sides of propodeum weakly convex or straight.
Petiole with relatively long peduncle, ventral face flat. Combined outline of dorsal surface of peduncle and anterior face of node deeply concave in the middle, posterior face of node slightly convex, anterodorsal and posterodorsal corner convex, dorsum rounded. Subpetiolar process produced as a small denticle, smaller than the diameter of the propodeal spiracle. Postpetiolar node rounded and lower than petiolar node. In dorsal view, petiolar node as broad as postpetiolar node (PTW 0.12-0.19, PPW 0.13-0.21) and petiolar node wider than long (PNL 0.09-0.14, PTW 0.12-0.19), anterior and posterior margins of petiole nearly straight, anterior margin of postpetiole concave and convex posterior margin, sides rounded in petiole and convex in postpetiole, narrowed posteriorly.
Dorsal surface of mandibles, upper median portion of clypeus and supraclypeal area smooth and shiny, with scattered piligerous punctae on head and mandibles. Head with longitudinal rugae along the gena, and frontal lobes. Lower median portion of clypeus with transverse rugae. In profile, posterolateral portion of cephalic dorsum smooth and shiny. Mesosoma smooth and shiny, except for propleuron and mesopleuron (areolate), and metapleuron (longitudinally rugulose). Ventral face of petiole and postpetiole longitudinally areolate. In dorsal view mesosoma, petiole, postpetiole and gaster smooth and shiny, except for declivity of propodeum, anterior and posterior face of petiole finely areolate.
Lateral margins and posterior margin of head with suberect to subdecumbent hairs. Scapes with subdecumbent to decumbent hairs. Outer margin of mandibles with short decumbent hairs. Mesosoma with short and long suberect hairs. Petiole and postpetiole with short subdecumbent hairs and long suberect hairs. Tibia with subdecumbent to decumbent hairs. Gaster with abundant suberect to decumbent hairs. Color yellowish ferruginous.
In profile view, promesonotum weakly convex, nearly flat, metanotal groove present. Propodeum about 1.3 times higher than long, dorsal face of propodeum convex, posterodorsal corners angulate, or with a small triangular tooth, anterodorsal corner convex, declivity concave with thin lateral laminae in direction of propodeal lobe. Propodeal lobes short and triangular. Propodeal spiracle rounded and situated above mid-height of sclerite by about two times the diameter of the spiracle, and beyond mid-length of sclerite by about 1.5 times the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum almost three times the diameter of the spiracle (PSL 0.03-0.05), and distance to declivity less than twice the diameter of the spiracle. In dorsal view, promesonotum about 1.25 times longer than wide, anterior margin rounded, sides convex; sides of propodeum straight.
Petiole with a relatively long peduncle, petiole longer than high (PTL 0.16-0.19, PTH 0.10-0.13), ventral face flat. Combined outline of dorsal surface of peduncle and anterior face of node deeply concave in the middle, posterior face of node slightly convex, anterodorsal and posterodorsal corner convex, dorsum rounded. Subpetiolar process produced as a small denticle, smaller than the diameter of the propodeal spiracle. Postpetiolar node strongly convex and lower than petiolar node. In dorsal view, petiolar node almost as broad as postpetiolar node (PTW 0.09-0.11, PPW 0.10-0.12), and petiolar node as broad as long (PNL 0.09-0.11, PTW 0.09-0.11), anterior and posterior margin of petiole convex, anterior margin of postpetiole concave and convex posteriorly, sides of petiole and postpetiole strongly convex.
Dorsal surface of mandibles, clypeus, supraclypeal area, and head smooth and shiny, with scattered piligerous punctae on head and mandibles. Head with transverse rugae near the posterior margin of head, gena and frontal lobes with longitudinal rugae. Mesosoma smooth and shiny, except for propleuron and mesopleuron (areolate), and metapleuron (finely areolate-rugose). Lateral margins of petiole finely areolaterugose, except for petiolar node and ventral face of postpetiole which are areolate. In dorsal view mesosoma, petiole, postpetiole and gaster smooth and shiny, except for declivity of propodeum, anterior and posterior face of petiole which are finely areolate.
Lateral margins of head and scape with subdecumbent to decumbent hairs. Posterior margin of head with short suberect hairs. Outer margin of mandibles with decum- bent hairs. Mesosoma with short and long suberect hairs. Petiole and postpetiole with short decumbent hairs and long subdecumbent hairs. Tibia with decumbent hairs. Gaster with longer suberect to decumbent hairs. Color yellowish ferruginous.
Distribution and biology. Carebara grandidieri is a widespread and common species in the Malagasy region, and has been recorded on Madagascar, Comoros and Mayotte ( Figure 68). This species was collected in the following environments: along the roadside, coastal scrub, dry forest, gallery forest, grassland, littoral forest, montane rainforest, open secondary vegetation, rainforest, spiny forest/thicket, tropical dry forest, Uapaca woodland, and urban/garden. C. grandidieri was sampled at elevations ranging from 10 m to 1550 m. Individuals and colonies were collected in rotten logs, rotting tree stumps, soil, termite mounds, leaf litter, under moss, litter on rocks, under rotten logs, under stones, and in leaf litter. Comments. Carebara grandidieri is widely distributed throughout Madagascar, Comoros and Mayotte, and co-occurs with almost all Carebara species recorded in the Malagasy region. The morphology of this species is highly variable (Figure 39, 40). There are different populations that initially appear to be distinct species. However, we could not find consistent characters to split C. grandidieri into additional species. The characters that vary across populations include: a) pilosity that varies from suberect to decumbent hairs, and is more noticeable on the gaster; b) posterior corner of propodeum, which varies from a pair of small triangular and angulate upwardly directed teeth, to nearly convex (in specimens from the same colony it is possible to see the gradual change from nearly convex to slightly dentate); c) petiole, where the node is thicker in profile and dorsal view, in some populations; and d) the diameter of the propodeal spiracle, which is smaller in populations from the north of Madagascar.
Upon examining all Carebara workers in the Malagasy region, we found only two species with nine antennal segments, C. grandidieri and C. creolei, and C. creolei is present only in Comoros and the Seychelles. All other Carebara species present in Madagascar have 10 or 11 antennal segments. The main character present in the queens of C. grandidieri and C. voeltzkowi described by Forel, is the presence of nine antennal segments, while the morphological differences between these specimens are not sufficient to merit placement in separate species. It is possible that C. grandidieri represents a species complex, with two or three different species, but much more detailed studies, including molecular studies, will likely be required to confirm this.
Diagnosis. Antennae ten-segmented. Major: Head subrectangular, posterior margin of head concave, lateral margins nearly straight and parallel; propodeum with a pair of small triangular teeth, dorsum of propodeum nearly flat; head with longitudinal and parallel rugose-reticulate and with longitudinal rugae laterally; posterolateral corners of head with a small, dentiform horn; gaster with abundant, suberect hairs. Minor: Head slightly longer than wide, nearly subquadrate; posterodorsal corner of propodeum with a pair of triangular teeth, dorsum nearly flat; combined outline of dorsal surface of peduncle and anterior face of node nearly straight, posterior margin vertical and slightly convex, anterodorsal corner convex; gaster with abundant suberect hairs. Head longer than wide (CI 75-82), in full-face view subrectangular, about 1.3 times longer than wide. Posterior margin of head concave, posterolateral corners rounded, lateral margins slightly convex. Mandibles with five teeth. Anterior margin of clypeus medially concave and laterally angulate. Antennae with ten segments. Scapes short (HL 0.56-0.68, SL 0.24-0.27, SI 38-44). Ocelli are absent. Eyes present, consisting of one ommatidium (EL 0.02-0.04). Supraclypeal area acutely triangular, extending forward beyond the antennal insertions.
In profile view, posterolateral corner of head with a short triangular tooth resembling a horn. Promesonotum high and convex, metanotal groove deep. Propodeum about 1.65 times higher than long, dorsal face of propodeum nearly flat and declining posteriorly, posterodorsal corners of propodeum each armed with a triangular tooth, declivity of propodeum vertical, flat with thin lateral laminae. Propodeal lobes triangular. Propodeal spiracle rounded and situated above mid-height of sclerite by about half the diameter of the spiracle, and beyond mid-length of sclerite by about the diameter of the spiracle; distance from propodeal spiracle to posterodorsal corner of propodeum about 2.5 times the diameter of the spiracle (PSL 0.06-0.07), and distance to declivity same as the diameter of the spiracle. In dorsal view, promesonotum almost as long as wide (about 1.02 times longer than wide), anterior margin and sides of promesonotum rounded, narrowed posteriorly; sides of propodeum weakly convex.
Petiole slightly longer than high (PTL 0.20-0.23, PTH 0.16-0.19) and with a short peduncle, ventral face weakly convex in the middle. Combined outline of dorsal surface of peduncle and anterior face of node slightly concave, nearly straight, posterior face of node vertical, nearly straight, anterodorsal corner convex, posterodorsal corner rounded, dorsum convex. Subpetiolar process produced as denticle, slightly larger than the diameter of the propodeal spiracle. Postpetiolar node rounded and lower than petiolar node. In dorsal view, petiolar node not as broad as postpetiolar node (PTW 0.12-0.16, PPW 0.18-0.21), petiolar node wider than long (PTW 0.12-0.16, PNL 0.08-0.10), anterior and posterior margin of petiole and postpetiole nearly straight, sides rounded in petiole and postpetiole.
Dorsal surface of mandibles, clypeus and supraclypeal area smooth and shiny, with piligerous punctae on head and mandibles. Head with longitudinal irregular and parallel rugose-reticulate, transverse irregular rugae near posterior margin of head, gena with longitudinal rugae extending to posterolateral lobes, reticulate close to posterolateral corners. In profile, posterolateral portion of cephalic dorsum smooth and shiny.
Mesosoma smooth and shiny, except for katepisternum (areolate) and metapleuron (areolate and with longitudinal and parallel rugae). Petiole and ventral face of postpetiole areolate. In dorsal view mesosoma, petiole, postpetiole and gaster, smooth and shiny, except for anterior and posterior faces of petiole which are areolate.
Lateral margins of head with short subdecumbent hairs, posterior margin of head with suberect hairs. Scapes with abundant appressed hairs. Outer margin of mandibles with decumbent hairs. Mesosoma with long and short erect and suberect hairs. Petiole and postpetiole with short decumbent hairs and longer subdecumbent hairs. Tibia with abundant decumbent hairs. Gaster with sparse, suberect hairs and abundant subdecumbent hairs. Color yellowish ferrugineus. Head slightly longer than wide (CI 87-92), in full-face view nearly subquadrate, about 1.1 times longer than wide. Posterior margin of head shallowly straight, posterolateral corners rounded, lateral margins weakly convex. Mandibles with five teeth. Anterior margin of clypeus almost straight and laterally angulate. Antennae with ten segments. Scape fails to reach the posterior margin of head (HL 0.35-0.39, SL 0.21-0.24, SI 60-64). Eyes present, consisting of one ommatidium (EL 0.01-0.02). Supraclypeal area triangular but poorly defined.
In profile view, promesonotum weakly convex, metanotal groove deeply impressed. Propodeum about 1.3 times higher than long, dorsal face of propodeum slightly concave and declining posteriorly, anterodorsal corner rounded, posterodorsal corners each armed with a triangular tooth, declivity slightly concave with thin lateral laminae. Propodeal lobes convex. Propodeal spiracle weakly oval and situated above mid-height of sclerite by about half the diameter of the spiracle, and beyond mid-length of sclerite by about the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about two times the diameter of the spiracle (PSL 0.02-0.05), and distance to declivity about 1.5 times the diameter of the spiracle. In dorsal view, promesonotum almost as long as wide (about 1.03 times longer than wide), anterior margin of promesonotum weakly convex, sides rounded and narrowed posteriorly; sides of propodeum convex.
Dorsal surface of head, mandibles, clypeus and supraclypeal area smooth and shiny, with scattered piligerous punctae on head and mandibles. Gena and frontal lobes with longitudinal rugae. Mesosoma smooth and shiny, except for katepisternum (areolate) and metapleuron (areolate and with longitudinal and parallel rugae). Petiole and ventral face of postpetiole areolate. In dorsal view, mesosoma, postpetiole and gaster smooth and shiny, except for petiole which is areolate.
Lateral margins and posterior margin of head with suberect hairs. Scapes with abundant subdecumbent hairs. Outer margin of mandibles with decumbent hairs. Mesosoma with short and long suberect hairs. Petiole, and postpetiole with short subdecumbent hairs and long suberect hairs. Tibia with appressed hairs. Gaster with abundant subdecumbent hairs. Color yellowish.
Distribution and biology. Carebara hainteny is known only from the center of Madagascar ( Figure 68) from grassland, montane rainforest and rainforest and was collected once in montane grassland. The species was sampled at different elevations from 785 m to 1300 m. C. hainteny was collected using Winkler traps, and found in rotten logs, leaf mold and rotten wood.
Comments. Carebara hainteny is endemic to Madagascar. This species can be easily distinguished from other species by the presence of well-defined, irregular and longitudinal rugoreticulate sculpture on the head; short, triangular, horn-like teeth on the posterolateral corners of the head; workers with a pair of triangular teeth on the propodeum, a thick petiolar node and the gaster with abundant suberect to subdecumbent hairs. Other five species, C. betsi, C. jajoby, C. kabosy, C. mahafaly, and C. nosindambo, were recorded at the same area, but can be separated from the others by the characters mentioned above.
In profile view, promesonotum high and strongly convex, metanotal groove deeply impressed, propodeum lower than promesonotum. Propodeum about as high as long, dorsal face of propodeum nearly flat and declining posteriorly, propodeum unarmed, posterodorsal corner bluntly angled, declivity of propodeum vertical and slightly con-cave. Propodeal lobes short and convex. Propodeal spiracle rounded and situated above mid-height of sclerite by about 1.5 times the diameter of the spiracle, and beyond midlength of sclerite by about two times the diameter of the spiracle, distance from propodeal spiracle to posterodrosal corner of propodeum about 1.8 times the diameter of the spiracle (PSL 0.04-0.07), and distance to declivity same as the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin and sides of promesonotum rounded, deeply narrowed posteriorly; sides of propodeum straight.
Petiole longer than high (PTL 0.22-0.30, PTH 0.16-0.21) and with relatively short peduncle, ventral face slightly convex. Petiolar node thick. Combined outline of dorsal surface of peduncle and anterior face of node slightly concave in the middle, posterior face of node vertical and weakly convex, anterodorsal corner convex, posterodorsal corner rounded, dorsum convex. Subpetiolar process produced as denticle, about as long as the diameter of the propodeal spiracle. Postpetiolar node rounded and lower than petiolar node. In dorsal view, petiolar node not as wide as postpetiolar node (PTW 0.16-0.21, PPW 0.18-0.24), petiolar node wider than long (PTW 0.16-0.21, PNL 0.12-0.15), anterior and posterior margins of petiole slightly convex, and nearly straight in postpetiole, sides rounded in petiole and postpetiole.
Dorsal surface of mandibles and head with scattered piligerous punctae. Frontoclypeal area, frons, and posterolateral portion of cephalic dorsum smooth and shiny. Head with longitudinal and parallel carinulae, extending from gena and frontal lobes to posterolateral corners, clypeus with transverse rugae. Mandibles with longitudinal striations, weakly imbricate close to posterior margin of head. In profile, posterolateral Head slightly longer than wide (CI 90-100), in full-face view nearly subquadrate, about 1.03 times longer than wide. Posterior margin of head nearly straight, posterolateral corners convex, lateral margins convex. Mandibles with five teeth. Anterior margin of clypeus weakly concave medially and laterally angulate. Antennae with ten segments. Scape fails to reach the posterior margin of head (HL 0.43-0.50, SL 0.29-0.32, SI 64-68). Eyes present, consisting of two ommatidia (EL 0.01-0.02). Supraclypeal area triangular but poorly defined.
In profile view, promesonotum weakly convex, nearly flat, metanotal groove deeply impressed. Propodeum about as high as long, dorsal face of propodeum flat and declining posteriorly, posterodorsal corner bluntly angled, anterodorsal corner rounded, declivity vertical and slightly concave. Propodeal lobes short and convex. Propodeal spiracle rounded and situated slightly above mid-height of sclerite by about half the diameter of the spiracle, and beyond mid-length of sclerite by about the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum and to declivity same as the diameter of the spiracle (PSL 0.03-0.04). In dorsal view, promesonotum almost as long as wide (about 1.06 times longer than wide), anterior margin of promesonotum rounded, sides convex; sides of propodeum weakly convex.
Petiole slightly longer than high (PTL 0.15-0.18, PTH 0.13-0.14) and with a short peduncle, ventral face medially convex. Combined outline of dorsal surface of peduncle and anterior face of node slightly concave, nearly straight, posterior face of node vertical and nearly straight, anterodorsal corner convex, posterodorsal corner rounded, dorsum convex. Subpetiolar process produced as a small denticle, smaller than the diameter of the propodeal spiracle. Petiolar node thick. Postpetiolar node rounded and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PPW 0.14-0.17, PTW 0.11-0.13), petiolar node wider than long (PTW 0.11-0.13, PNL 0.09-0.10), anterior and posterior margin of petiole slightly convex, and nearly straight in postpetiole, sides of petiole rounded and convex in postpetiole.
Dorsal surface of head, mandibles, clypeus and supraclypeal area smooth and shiny, with scattered piligerous punctae on head and mandibles, gena and frontal lobes longitudinally carinulate. Mesosoma smooth and shiny, except for katepisternum (areolate), and metapleuron (finely and longitudinally areolate). Petiole and ventral face of postpetiole areolate. In dorsal view, mesosoma, petiole, postpetiole and gaster smooth and shiny, except for declivity of propodeum which is weakly sculptured.
Lateral margins and posterior margin of head with suberect hairs. Scapes with subdecumbent hairs. Outer margin of mandible with short decumbent hairs. Mesosoma with long and short erect hairs. Petiole, postpetiole and gaster with abundant subdecumbent hairs, and sparse and long suberect hairs. Tibia with decumbent hairs. Color yellowish ferruginous.
Distribution and biology. Carebara hiragasy is known only from the southwestern and southeastern sections of Madagascar ( Figure 68). This species was found in montane rainforest and rainforest (transition to montane forest). C. hiragasy was collected at 600 m and 1100 m, in soil and under stones.
Comments. Carebara hiragasy is endemic to two localities in the southwest and southeast of Madagascar. The major workers are easily recognized by the following characters: head longer than wide, with the posterolateral corners rounded; the propodeum unarmed; and the anterodorsal corner of the petiole convex. In minor workers: the head nearly subquadrate; the propodeum unarmed; and long erect to suberect hairs on the head and body, except for those on the scape and tibia which are decumbent. Other nine species were recorded at the same localities: C. bara, C. dota, C. grandidieri, C. hainteny, C. jajoby, C. nosindambo, C. omasi, C. placida and C. sampi, but C. hiragasy can be separated from the others by the combination of characters mentioned above.

Carebara jajoby
In profile view, posterolateral corner of head with a small, obtuse tooth resembling a horn. Promesonotum high and nearly rounded, metanotal groove deeply impressed. Propodeum lower than promesonotum. Propodeum about 1.75 times higher than long, dorsal face of propodeum nearly flat, to weakly concave, declining posteriorly; posterodorsal corners of propodeum each armed with a triangular tooth; anterodorsal corner convex, declivity vertical and concave with narrow lateral laminae. Propodeal lobes short and convex. Propodeal spiracle rounded and situated above mid-height of sclerite, and beyond mid-length of sclerite by about half the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about four times the diameter of the spiracle (PSL 0.06-0.18), and distance to declivity almost twice the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin and sides of promesonotum rounded; sides of propodeum straight.
Petiole longer than high (PTL 0.21-0.43, PTH 0.16-0.27) and with relatively long peduncle, ventral face weakly convex in the middle. Combined outline of dorsal surface of peduncle and anterior face of node concave or nearly straight, posterior face of node vertical, anterodorsal corner convex, posterodorsal corner rounded, dorsum convex. Subpetiolar process produced as a very small denticle, same as or slightly shorter than the diameter of the propodeal spiracle. Postpetiolar node rounded and lower than petiolar node. In dorsal view, petiolar node not as broad as postpetiolar node (PPW 0.18-0.33, PTW 0.14-0.27) and petiolar node wider than long (PTW 0.14-0.27, PNL 0.08-0.15), anterior margins of petiole and postpetiole nearly straight, sides of petiole rounded, convex in postpetiole, narrowed posteriorly.
Dorsal surface of mandibles, clypeus, supraclypeal area and frons smooth and shiny, with scattered piligerous punctae on head and mandibles. Head with longitudinal rugae directed to posterior margin, gena with well-developed longitudinal rugae directed to posterolateral corners of head. In profile, posterolateral portion of cephalic dorsum smooth and shiny, larger specimens with weakly marked longitudinal rugae. Sides of pronotum with transverse and longitudinal fine rugae, median area unsculptured on smaller major workers; katepisternum areolate, metapleuron finely areolate. Petiole and ventral face of postpetiole areolate. In dorsal view, mesosoma, petiole, postpetiole and gaster smooth and shiny; propodeum weakly sculptured.
Lateral margins with long suberect hairs and short appressed hairs. Scapes with appressed hairs. Outer margin of mandible with short and sparse appressed hairs. Mesosoma with short decumbent to appressed hairs, and long suberect or subdecumbent hairs. Petiole and postpetiole with short decumbent or appressed hairs and long subdecumbent hairs. Tibia with appressed hairs. Gaster with short decumbent hairs and long subdecumbent hairs. Color yellowish ferruginous.
In profile view, promesonotum weakly convex, nearly flat, metanotal groove deeply impressed. Propodeum about 1.58 times higher than long, dorsal face of propodeum flat, declining posteriorly, anterodorsal corner rounded, posterodorsal corners each armed with a triangular tooth, declivity vertical and nearly flat, with thin lateral laminae. Propodeal lobes short and convex. Propodeal spiracle nearly oval and situated above mid-height of sclerite by about half the diameter of the spiracle, and beyond mid-length of sclerite by about 1.5 times the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about 2.5 times the diameter of the spiracle (PSL 0.03-0.07), and distance to declivity same as the diameter of the spiracle. In dorsal view, promesonotum about 1.16 times longer than wide, anterior margin rounded, sides convex and narrowed posteriorly; sides of propodeum weakly convex.
Lateral margins and posterior margin of head with short decumbent hairs, and long suberect hairs. Scapes with abundant decumbent hairs. Outer margin of mandible with decumbent hairs. Mesosoma with short decumbent hairs and long suberect or subdecumbent hairs. Petiole and postpetiole with short decumbent hairs and longer subdecumbent hairs. Tibia with appressed hairs. Gaster with abundant decumbent hairs and long subdecumbent hairs. Color yellowish ferruginous.
Distribution and biology. Carebara jajoby is known from the east and northwest of Madagascar (Figure 68). This species was mainly found in littoral rainforest, montane rainforest, montane shrubland, rainforest, and rainforest (transition to montane forest). C. jajoby is distributed in elevations ranging from 10 m to 2000 m. Specimens were collected using maxi-Winkler traps. Individuals and colonies were found in the following microhabitats: dead twigs above ground, rotten logs, rotten logs in root mat, ground nests, sifted litter, leaf mold, rotten wood, under rootmat, litter on rocks, and under stones.
Comments. Carebara jajoby can be confused with the following species: C. sampi, C. vazimba, and C. kabosy, but can be separated from them by the following combination of characters. In major workers, dorsum of head of C. sampi is smooth and shiny or with fine longitudinal rugae laterally. In case the dorsum of head presents well-defined longitudinal rugae like C. vazimba, C. kabosy, and C. jajoby then the propodeal tooth of C. jajoby is longer than the diameter of the propodeal spiracle. In minor workers, C. jajoby can be separated from the others species by the prescence of abundant subdecumbent hairs in the gaster, and with fewer than ten longer suberect hairs. C. jajoby is distributed from the east and northwest of Madagascar, while C. sampi is distributed from south and southwestern, C. vazimba is distributed in the north, northeastern and northwestern. Other nine species were recorded at the same localities: C. bara, C. betsi, C. grandidieri, C. hainteny, C. hiragasy, C. kabosy, C. mahafaly, C. nosindambo, and C. placida. Head longer than wide (CI 75-84), in full-face view nearly subrectangular, about 1.2 times longer than wide. Posterior margin of head deeply concave in the middle, posterolateral corners well developed, rounded and narrowed posteriorly, lateral margins convex to nearly straight. Mandibles with six teeth. Anterior margin of clypeus concave, and laterally convex. Ocelli absent or present. Antennae with ten segments. Scapes short (HL 0.63-1.16, SL 0.25-0.41, SI 29-43). Eyes present, consisting of one or more ommatidia (EL 0.01-0.09). Supraclypeal area short, triangular and well defined.
In profile view, posterolateral corner of head with a small angulate tooth. Promesonotum high and nearly rounded, metanotal groove deeply impressed. Propodeum lower than promesonotum, and about 15 times higher than long, dorsal face of propodeum flat and declining posteriorly, posterodorsal corners each armed with a triangular tooth, declivity of propodeum concave with thin lateral laminae. Propodeal lobes short and convex. Propodeal spiracle rounded and situated above mid-height of sclerite by about half the diameter of the spiracle, and beyond mid-length of sclerite by about the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about four times the diameter of the spiracle (PSL 0.06-0.14), and distance to declivity about 1.5 times the diameter of the spiracle. In dorsal view, anterior margin and sides of promesonotum rounded, and about as long as wide; sides of propodeum straight.
Petiole longer than high (PTL 0.19-0.36, PTH 0.15-0.28) and with relatively short peduncle, ventral face medially convex. Combined outline of dorsal surface of peduncle and anterior face of node medially concave, posterior face of node vertical and nearly straight, anterodorsal and posterodorsal corners rounded, dorsum nearly rounded. Subpetiolar process produced as small denticle, almost as large as the diameter of the propodeal spiracle. Postpetiolar node rounded and slightly lower than petiolar node. In dorsal view, postpetiolar node slightly wider than petiolar node (PTW 0.13-0.25, PPW 0.17-0.32) and petiolar node wider than long (PNL 0.09-0.15, PTW 0.13-0.25), anterior and posterior margins of petiole straight, anterior margin of postpetiole straight, and posterior margin convex, sides rounded in petiole, and postpetiole.
Dorsal surface of mandibles, clypeus, supraclypeal area and frons smooth and shiny, with scattered piligerous punctae on head and mandibles. Head with longitudinal and parallel rugae directed to posterior margin of head, gena with longitudinal rugae extending to posterolateral corners. Posterolateral portion of cephalic dorsum smooth and shiny. Sides of pronotum finely areolate, median area smooth and shiny on small and median major workers, areolate katepisternum, metapleuron with longitudinal rugae and finely areolate. Anterior margin of pronotum finely areolate. Petiole, ventral and lateral margins of postpetiole areolate. In dorsal view, promesonotum, and postpetiole smooth and shiny medially, propodeum and petiole finely areolate.
Lateral margins of head with short decumbent hairs and long suberect hairs. Posterior margin of head with short and long suberect hairs. Scapes with appressed hairs. Outer margin of mandibles with short appressed hairs. Mesosoma with short and long suberect hairs. Petiole with long subdecumbent hairs, postpetiole with short appressed hairs and long decumbent hairs. Tibia with appressed hairs. Gaster with short decumbent or appressed hairs and long suberect or sudecumbent hairs. Color yellowish ferruginous. Head longer than wide (CI 84-95), in full-face view nearly subrectangular, about 1.2 times longer than wide. Posterior margin of head slightly concave in the middle, posterolateral corners rounded, lateral margins slightly convex. Mandibles with five teeth. Anterior margin of clypeus almost straight, and laterally angulate. Antennae with ten segments. Scape fails to reach the posterior margin of head (HL 0.35-0.44, SL 0.22-0.28, SI 61-68). Eyes present, consisting of one ommatidium (EL 0.01-0.02). Supraclypeal area triangular but not well defined.
In profile view, promesonotum weakly convex, nearly flat, metanotal groove deeply impressed. Propodeum about 1.4 times higher than long, dorsal face of propodeum flat and declining posteriorly, anterodorsal corner of propodeum weakly convex, posterodorsal corners each armed with a small triangular tooth, declivity weakly concave with thin lateral laminae. Propodeal lobes short and convex. Propodeal spiracle nearly oval and situated weakly above mid-height of sclerite by about half the diameter of the spiracle, and beyond mid-length of sclerite by about 1.5 times the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about 2.5 times the diameter of the spiracle (PSL 0.04-0.06), and distance to declivity almost the same as the diameter of the spiracle. In dorsal view, anterior margin of promesonotum convex, sides convex and narrowed posteriorly, slightly longer than wide; sides of propodeum straight.
Petiole longer than high (PTL 0.12-0.20, PTH 0.10-0.13) and with a short peduncle, ventral face medially convex. Combined outline of dorsal surface of peduncle and anterior face of node medially concave, posterior face weakly convex, anterodorsal and posterodorsal corner rounded, dorsum nearly rounded. Subpetiolar process is reduced to a small convexity, shorter than the diameter of the propodeal spiracle. Postpetiolar node convex and lower than petiolar node. In dorsal view, petiolar node not as broad as postpetiolar node (PTW 0.08-0.11, PPW 0.11-0.15), petiolar node wider than long (PNL 0.07-0.08, PTW 0.08-0.11), anterior and posterior margins of petiole weakly convex, and nearly straight in postpetiole.
Dorsal surface of mandibles, clypeus, supraclypeal area and frons smooth and shiny, with scattered piligerous punctae on head and mandibles. Gena and frontal lobes with longitudinal rugae, and transversely rugose close to posterior margin of head. Mesosoma smooth and shiny, except for katepisternum (areolate) and metapleuron (areolate and with longitudinal rugosities). Petiole and ventral face of postpetiole areolate. In dorsal view, dorsal face of promesonotum, postpetiole and gaster smooth and shiny; anterior margin of promesonotum, dorsum of propodeum and petiole finely areolate.
Lateral margins and posterior margin of head and scape with decumbent hairs. Outer margin of mandibles with appressed hairs. Mesosoma with short subdecumbent hairs and long suberect or subdecumbent hairs. Petiole and postpetiole with short appressed hairs and long subdecumbent hairs. Tibia with appressed hairs. Gaster with short decumbent or appressed hairs and long subdecumbent hairs. Color yellowish ferruginous.
Distribution and biology. Carebara kabosy was found in the north, northeastern and northwestern areas of Madagascar ( Figure 68). The main habitats were montane forest, montane rainforest, rainforest, and tropical forest. C. kabosy is distributed at elevations ranging from 25 m to 1325 m. The specimens were collected using maxi-Winkler and pitfall traps. The microhabitats where it occurs include rotten logs, rotten tree stumps, sifted litter, leaf mold, rotten wood, under moss on rotten logs, and under stones. Comments. Carebara kabosy can be confused with C. vazimba but can be separated by the length of the propodeal tooth, which is shorter than propodeal spiracle diameter in C. vazimba while in C. kabosy is slightly longer. C. kabosy is distributed in the north, northeastern and northwestern areas of Madagascar, while C. vazimba is present in the north of Madagascar. Other twelve species were recorded at the same localities: C. bara, C. berivelo, C. betsi, C. demeter, C. grandidieri, C. hainteny, C. jajoby, C. mahafaly, C. malagasy, C. nosindambo, C. raberi, and C. salegi.

Carebara lova
In profile view, posterolateral corner of head with a small angulate triangular tooth resembling a horn. Promesonotum high and nearly rounded, metanotal groove deeply impressed. Propodeum lower than promesonotum, and about 1.5 times higher than long, dorsal face of propodeum nearly flat, and declining posteriorly, propodeum armed, posterodorsal corners each armed with a small laminate triangular tooth, declivity concave with thin lateral laminae. Propodeal lobes short and convex. Propodeal spiracle nearly oval and situated slightly above mid-height of sclerite, and barely beyond mid-length of sclerite by about half the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about 2.5 times the diameter of the spiracle (PSL 0.05-0.12), and distance to declivity about 1.8 times the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin and sides rounded, slightly narrowed anteriorly and posteriorly; sides of propodeum straight.
Dorsal surface of mandibles, clypeus, supraclypeal area and frons smooth and shiny, with scattered piligerous punctae on head and mandibles. Dorsolateral faces of head with longitudinal rugae, gena and frontal lobes with longitudinal rugae extending to posterior border of posterolateral corners. In profile, posterolateral portion of cephalic dorsum smooth and shiny. Mesosoma smooth and shiny, except for katepisternum and metapleuron, which are longitudinally areolate-rugose. Petiole, ventral face, and lateral margins of postpetiole areolate. In dorsal view, promesonotum, petiole, postpetiole and gaster smooth and shiny, except for propodeum which is finely areolate.
Lateral margins of head with short appressed hairs and long suberect hairs. Posterior margin of head with short and long suberect hairs. Scapes with appressed hairs. Outer margin of mandibles with sparse and short appressed hairs. Mesosoma with short and long suberect hairs. Petiole and postpetiole with short decumbent to appressed hairs and long subdecumbent hairs. Tibia with appressed hairs. Gaster with short decumbent to appressed hairs and dispersed, long suberect hairs. Color yellowish ferruginous.
Description of minor workers. Measurements (   Head longer than wide (CI 83-95), in full-face view nearly subquadrate, about 1.1 times longer than wide, narrowed anteriorly and posteriorly. Posterior margin of head nearly straight to weakly concave medially, posterolateral corners rounded, lateral margins convex. Mandibles with five teeth. Anterior margin of clypeus nearly straight, and laterally convex. Antennae with ten segments. Scape fails to reach the posterior margin of head . Eyes present, consisting of one ommatidium (EL 0.01-0.02). Supraclypeal area triangular but not well defined.
In profile, promesonotum slightly convex, nearly flat, metanotal groove present. Propodeum about 1.4 times higher than long, dorsal face of propodeum nearly flat to weakly convex, and declining posteriorly, propodeum armed, posterodorsal corners each armed with a small triangular tooth, declivity concave with thin lateral laminae. Propodeal lobes short and convex. Propodeal spiracle rounded and situated above midheight of sclerite by about half the diameter of the spiracle, and beyond mid-length of sclerite by about the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum almost the same as the diameter of the spiracle (PSL 0.03-0.05), and distance to declivity less than half the diameter of the spiracle. In dorsal view, anterior margin of promesonotum convex, sides rounded and narrowed posteriorly, slightly longer than wide; sides of propodeum straight.
Petiole longer than high (PTL 0.11-0.14, PTH 0.09-0.11) and with relatively short peduncle, ventral face medially convex. Combined outline of dorsal surface of peduncle and anterior face of node medially concave, posterior face of node weakly convex, anterodorsal corner convex and posterodorsal corner rounded, dorsum nearly rounded. Subpetiolar process produced as a small denticle, weakly shorter than the diameter of the propodeal spiracle. Postpetiolar node nearly rounded and lower than petiolar node. In dorsal view, postpetiolar node slightly wider than petiolar node (PTW 0.08-0.09, PPW 0.10-0.13), and petiolar node wider than long (PNL 0.05-0.07, PTW 0.08-0.09), anterior margin of petiole convex, posterior margin nearly straight, anterior and posterior margin of postpetiole nearly straight, sides of petiole and postpetiole rounded.
Dorsal surface of mandibles, clypeus, supraclypeal area and frons smooth and shiny, with scattered piligerous punctae on head and mandibles. Gena and frontal lobes with longitudinal rugae. Mesosoma smooth and shiny, except for katepisternum, metapleuron and propodeum which are areolate. Petiole and ventral face of postpetiole areolate. In dorsal view, promesonotum, postpetiole and gaster smooth and shiny; propodeum and petiole areolate.
Posterior and lateral margins of head with short decumbent hairs. Scapes with appressed hairs. Outer margin of mandibles with short appressed hairs. Mesosoma with short suberect hairs and long erect hairs. Petiole and postpetiole with short decumbent hairs and long subdecumbent hairs. Tibia with appressed hairs. Gaster with short decumbent hairs and long suberect hairs. Color yellowish ferruginous.
Distribution and biology. Carebara lova is known only from Madagascar, distributed in the northwestern part of the island (Figure 68). This species occurs in the following ecosystems: gallery forest, gallery forest on sandy soil, rainforest and tropical dry forest. It was collected at elevations ranging from 30 m to 500 m. Individuals and colonies were found in sifted litter, rotten logs, leaf mold, and rotten wood. All specimens were collected using maxi-Winkler and pitfall traps. Comments. Carebara lova can be confused with C. sampi but can be separated by the distance from posterior border of propodeal spiracle to declivity, which is less than two times the diameter of the spiracle in C. sampi and is same as or less than the diameter of the spiracle in C. lova. C. lova is distributed in the northwestern area of Madagascar while C. sampi is distributed in the south and southwestern of Madagascar. Other two species were recorded at the same localities: C. bara, and C. grandidieri.
C. lova have three intermediates in the major worker subcaste (Figure 48). The posterolateral corner of the head of intermediates 2 and 3 is nearly rounded, and slightly narrowed posteriorly in intermediate 1; the posterior margin of the head is deeply concave in all intermediates. The lateral margins of the head are nearly straight in bigger major workers, and slightly convex in smaller and medium major workers. The eyes are small and reduced to one ommatidium in the smaller and medium intermediates,but may consist of up to four ommatidia in the bigger ones. Ocelli are absent in the smaller and medium major workers, but present and well developed in the big major workers (one ocellus). Reduced flight sclerites are present in the largest intermediate. The dorsum of the mesosoma is convex anteriorly and gradually slopes to the declivity in intermediate 3. The dorsum of the promesonotum is high and strongly convex in intermediates 1 and 2. The shape of the petiole and postpetiole vary little in all intermediates, although the anterior margin of the petiole is nearly straight in intermediate 3 and the petiolar node is thinner than that of intermediates 1 and 2. The propodeum is armed with a pair of triangular teeth in all intermediates. Frons smooth and shiny, dorsolateral faces with finely longitudinal and parallel rugae in full-face view in all intermediates. The pilosity on the head and body follows the same pattern in all intermediates, with intermediate 3 with more abundant, short decumbent hairs on the gaster.

Carebara mahafaly
Diagnosis. Antennae ten-segmented. Major: Head slightly longer than wide, nearly subquadrate, lateral margins strongly convex; posterior margin of head deeply concave; dorsum of propodeum weakly convex, nearly flat; posterodorsal corner of propodeum with a pair of laminate triangular teeth; petiolar node thick, combined outline of dorsal surface of peduncle and anterior face of node concave and posterior face vertical and weakly convex; gaster with short appressed hairs. Minor: Head slightly longer than wide, narrowed anteriorly; lateral margins of head slightly convex; posterior margin of head straight; dorsum of propodeum medially concave, posterodorsal corner with a pair of laminate triangular teeth; petiolar node thick, combined outline of dorsal surface of peduncle and anterior face of node slightly concave in the middle, dorsum slightly convex; gaster with short appressed hairs. Head slightly longer than wide (CI 87-88), in full-face view nearly subquadrate, about 1.1 times longer than wide. Posterior margin of head deeply concave in the middle, posterolateral corners well developed and rounded, lateral margins strongly convex. Mandibles with six teeth. Anterior margin of clypeus nearly straight, and laterally convex. Ocelli present or absent. Antennae with ten segments. Scapes short . Eyes present, consisting of one ommatidium (EL 0.02-0.03). Supraclypeal area acutely triangular and well defined.
In profile view, promesonotum high and strongly convex, metanotal groove deeply impressed, propodeum about 1.8 times higher than long, and lower than promesonotum, dorsal face of propodeum nearly flat and declining posteriorly, propodeum armed, posterodorsal corners each armed with a triangular laminate tooth, anterodorsal corner slightly convex, declivity weakly concave, nearly flat, with thin lateral laminae. Propodeal lobes convex. Propodeal spiracle rounded and situated above mid-height of sclerite by about the diameter of the spiracle, and beyond mid-length of sclerite by about half the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about 3.5 times the diameter of the spiracle (PSL 0.08-0.09), and distance to declivity about 2.2 times the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin and sides of promesonotum rounded and narrowed posteriorly; sides of propodeum straight.
Petiole longer than high (PTL 0.22-0.25, PTH 0.17-0.18) and with relatively long peduncle, ventral face medially convex. Combined outline of dorsal surface of peduncle and anterior face of node medially concave, posterior face of node vertical and nearly straight, anterodorsal corner strongly convex, posterodorsal corner rounded, dorsum convex. Subpetiolar process absent, when present, reduced to a small convexity. Postpetiolar node nearly rounded and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PTW 0.12-0.15, PPW 0.17-0.20) and petiolar node wider than long (PNL 0.09-0.11, PTW 0.12-0.15), anterior margin of petiole straight, posterior margin convex, anterior margin of postpetiole concave and posterior margin convex, sides rounded in petiole and postpetiole.
Dorsal surface of mandibles, clypeus, supraclypeal area and the median portion of the frons smooth and shiny, with scattered piligerous punctae on head and mandibles. Head with finely longitudinal and parallel rugae, except for median area and near posterior margin, gena with longitudinal rugae, extending to eye level, frontal lobes with longitudinal rugae, extending to antennae level. In profile, posterolateral portion of cephalic dorsum smooth and shiny. Mesosoma smooth and shiny, except katepisternum and metapleuron (areolate-rugose), and propodeum (areolate). Petiole and ventral face of postpetiole areolate. In dorsal view, promesonotum, petiole, postpetiole and gaster smooth and shiny except for propodeum which is areolate.
Lateral margins of head with short appressed hairs, posterior margin with short and long subdecumbent hairs. Scapes with appressed hairs. Outer margin of mandibles with short and sparse appressed hairs. Mesosoma with short and long suberect hairs.
Petiole and postpetiole with short appressed hairs and long subdecumbent hairs. Tibia with short appressed hairs. Gaster with short appressed hairs and sparse and long decumbent hairs. Color yellowish ferruginous.
Description of minor workers. Measurements (   Head longer than wide (CI 86-93), in full-face view nearly subquadrate, about 1.1 times longer than wide and slightly narrowed anteriorly. Posterior margin of head nearly straight, posterolateral corners rounded, lateral margins convex. Mandibles with five teeth. Anterior margin of clypeus slightly concave, and laterally convex. Antennae with ten segments. Scape fails to reach the posterior margin of head . Eyes present, consisting of one ommatidium (EL 0.01-0.02). Supraclypeal area triangular but poorly defined.
In profile view, promesonotum weakly convex, metanotal groove deeply impressed. Propodeum about 1.1 times higher than long, dorsal face of propodeum weakly convex and declining posteriorly, propodeum armed, posterodorsal corners each armed with a laminate triangular tooth, anterodorsal corner rounded and at same height as posterodorsal corner of promesonotum, declivity flat to slightly convex with thin lateral laminae. Propodeal lobes convex. Propodeal spiracle rounded and situated slightly above mid-height of sclerite by about half the diameter of the spiracle, and beyond mid-length of sclerite by about 1.5 times the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about three times the diameter of the spiracle (PSL 0.04-0.06), and distance to declivity same as the diameter of the spiracle. In dorsal view, anterior margin and sides of promesonotum rounded, narrowed posteriorly, slightly longer than wide; sides of propodeum straight.
Petiole longer than high (PTL 0.13-0.18, PTH 0.10-0.13) and with relatively long peduncle, ventral face medially convex. Combined outline of dorsal surface of peduncle and anterior face of node medially concave, posterior face of node slightly convex, anterodorsal corner convex, posterodorsal corner rounded, dorsum nearly rounded. Subpetiolar process is reduced to a small convexity, not longer than the diameter of the propodeal spiracle. Postpetiolar node rounded and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PTW 0.08-0.10, PPW 0.11-0.15), and petiolar node as wide as long, anterior margin of petiole strongly convex, posterior margin rounded, anterior margin of postpetiole nearly straight, posterior margin rounded, sides convex in petiole and postpetiole, narrowed posteriorly in postpetiole.
Lateral margins of head with short appressed hairs, posterior margin with short subdecumbent hairs. Scapes with appressed hairs. Outer margin of mandibles with decumbent hairs. Mesosoma with short and long suberect to subdecumbent hairs. Petiole, postpetiole, tibia and gaster with short appressed hairs. Color yellowish ferruginous.
Distribution and biology. Carebara mahafaly is known from two localities in the center of Madagascar (Figure 69). This species occurs in the rainforest and montane rainforest and was found at elevations of 780 m and 1300 m. Individuals and colonies were collected in sifted litter, leaf mold and rotten wood. Specimens were collected using maxi-Winkler and pitfall traps.
Comments. Carebara mahafaly is endemic to the center of Madagascar. Other six species were recorded at the same localities: C. betsi, C. grandidieri, C. hainteny, C. jajoby, C. kabosy, and C. nosindambo. This species can be confused with C. salegi, especially in the shape of the head. C. mahafaly can be differentiated from C. salegi and other species by the following combination of characters: head slightly longer than wide, nearly subquadrate in full-face view, posterolateral corners rounded, lateral margins of head convex; propodeum with a pair of upwardly directed triangular teeth, and anterodorsal corner of petiole convex, additional to this C. salegi was recorded only in the north of Madagascar. C. mahafaly does not have intermediates in the major worker subcaste.

Carebara malagasy
Diagnosis. Antennae ten-segmented. Major: Head subrectangular, longer than wide, lateral margins weakly convex and narrowed at the top, posterolateral corners well developed, posterior margin of head deeply concave; dorsum of propodeum Head longer than wide (CI 73-83), in full-face view nearly subrectangular, about 1.2 times longer than wide, narrowed at the top. Posterior margin of head deeply concave, posterolateral corners well developed and rounded, lateral margins weakly convex. Mandibles with six teeth. Anterior margin of clypeus slightly concave, and laterally convex. Ocelli present or absent. Antennae with ten segments. Scapes short . Eyes present, consisting of one ommatidium (EL 0.01-0.05). Supraclypeal area short and triangular, but shallowly impressed.
In profile, promesonotum high and nearly rounded, metanotal groove deeply impressed. Propodeum lower than promesonotum, and about 1.6 times higher than long, dorsal face of propodeum weakly convex and declining posteriorly, propodeum unarmed, anterodorsal corner rounded, posterodorsal corner angulate, declivity weakly concave. Propodeal lobes convex. Propodeal spiracle nearly oval and situated above mid-height of sclerite, and beyond mid-length of sclerite by about half the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about twice the diameter of the spiracle (PSL 0.04-0.10), and distance to declivity about 1.5 times the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, narrowed posteriorly, anterior margin and sides of promesonotum rounded; sides of propodeum straight.
Petiole longer than high (PTL 0.17-0.36, PTH 0.13-0.25) and with relatively long peduncle, ventral face slightly convex in the middle. Combined outline of dorsal surface of peduncle and anterior face of node concave, posterior face of node vertical and nearly straight, anterodorsal corner convex, posterodorsal corner rounded, dorsum convex. Subpetiolar process produced as denticle, slightly larger than the diameter of the propodeal spiracle. Postpetiolar node nearly rounded and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PTW 0.12-0.23, PPW 0.16-0.32) and petiolar node wider than long (PNL 0.08-0.14, PTW 0.12-0.23), anterior and posterior margins of petiole and postpetiole nearly straight, sides convex in petiole and nearly rounded in postpetiole.
Dorsal surface of mandibles, clypeus, supraclypeal area and frons smooth and shiny, with scattered piligerous punctae on head and mandibles. Head with finely longitudinal rugae directed toward posterior margin of head. Gena and frontal lobes with longitudinal rugae. Mesosoma smooth and shiny, except for katepisternum (areolate-rugose) and metapleuron (areolate with longitudinal rugae). Petiole and ventral face of postpetiole areolate. In dorsal view, mesosoma, petiole, postpetiole and gaster smooth and shiny.
Lateral margins and posterior margin of head with short subdecumbent hairs and longer suberect hairs. Scapes with appressed hairs. Outer margin of mandible with short and appressed hairs. Mesosoma with short and long suberect hairs. Petiole and postpetiole with short decumbent to appressed hairs and long subdecumbent hairs. Tibia with appressed hairs. Gaster with short decumbent hairs, and long suberect to subdecumbent hairs. Color yellowish ferruginous.
Head longer than wide (CI 86-94), in full-face view nearly subrectangular, about 1.2 times longer than wide, slightly narrowed anteriorly. Posterior margin slightly convex, posterolateral corners rounded, lateral margins slightly convex. Mandibles with six teeth. Anterior margin of clypeus straight, and laterally with a laminate angulate tooth. Antennae with ten segments. Scape fails to reach the posterior margin of head . Eyes present, consisting of one ommatidium (EL 0.01-0.02). Supraclypeal area short and triangular but poorly defined.
In profile view, promesonotum weakly convex, metanotal groove weakly impressed. Propodeum about 1.6 times higher than long, dorsal face of propodeum slightly convex and declining posteriorly, propodeum unarmed, anterodorsal corner slightly convex, posterodorsal corner angulate, declivity nearly flat, with thin lateral laminae. Propodeal lobes convex. Propodeal spiracle rounded and situated slightly above mid-height of sclerite by about half the diameter of the spiracle, and beyond mid-length of sclerite by about 1.5 times the diameter of the spiracle, distance from propodeal spiracle to postedorsal corner of propodeum and to declivity almost the same as the diameter of the spiracle (PSL 0.02-0.04). In dorsal view, promesonotum about 1.1 times longer than wide, anterior margin and sides of promesonotum nearly rounded, and narrowed posteriorly; sides of propodeum weakly convex.
Petiole slightly longer than high (PTL 0.11-0.14, PTH 0.09-0.10) and with a short peduncle, ventral face medially convex. Combined outline of dorsal surface of peduncle and anterior face of node weakly concave, posterior face of node slightly convex, anterodorsal and posterodorsal corner rounded, dorsum convex. Subpetiolar process produced as a small denticle, slightly smaller than the diameter of the propodeal spiracle. Postpetiolar node nearly rounded and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PTW 0.07-0.08, PPW 0.10-0.12), and petiolar node wider than long (PNL 0.06-0.07, PTW 0.07-0.08), anterior and posterior margins of petiole and postpetiole nearly straight, sides nearly rounded in petiole and postpetiole.
Dorsal surface of head, mandibles, clypeus and supraclypeal area smooth and shiny, with scattered piligerous punctae on head and mandibles. Gena and frontal lobes with short longitudinal rugae. Mesosoma smooth and shiny, except for katepisternum (areolate) and metapleuron (finely areolate-rugose). Petiole and ventral face of postpetiole areolate. In dorsal view, promesonotum, postpetiole and gaster smooth and shiny, except for propodeum and petiole which are weakly areolate.
Lateral margins and posterior margin of head with decumbent hairs. Scapes with appressed hairs. Outer margin of mandible with decumbent hairs. Mesosoma with short and long suberect to subdecumbent hairs. Petiole, and postpetiole with short decumbent hairs and longer subdecumbent hairs. Tibia with appressed hairs. Gaster with short decumbent hairs and sparse long subdecumbent hairs. Color yellowish ferruginous.
Distribution and biology. Carebara malagasy is known from the north of Madagascar ( Figure 69). This species was found in littoral rainforest and tropical dry forest and collected at elevations ranging from 25 m to 500 m. Individuals and colonies were found under stones, in leaf mold and rotten wood. Specimens were collected using maxi-Winkler and pitfall traps.
Comments. Carebara malagasy can be confused with other species but can be separated from other species by the following combination of characters: form of the propodeum, which is unarmed or armed with at least a dentiform angle, dorsum of head with at least the frons smooth and shiny, and posterolateral corners of head narrowing posteriorly. Carebara malagasy is endemic to the north of Madagascar, and other five species were recorded at this area: C. bara, C, berivelo, C. grandidieri, C. kabosy, and C. tana.  Antsiranana, Forêt d'Ampombofofo, -12.09949, 49.33874, 25 m, littoral forest, 21-22.xi.2007, (B.L. Fisher et al.); Antsiranana, Forêt d'Orangea, 3.6 km 128° SE Remena, -12.25889, 49.37467, 90 m, littoral rainforest, 22-28.ii.2001, (Fisher, Griswold et al.). Diagnosis. Antennae ten-segmented. Major: Head nearly subrectangular, longer than wide, lateral margins straight, posterior margin of head concave to deeply concave; dorsum of propodeum flat and declining posteriorly, posterodorsal corner with a pair of triangular teeth; head with longitudinal and parallel rugae, except the frons; gaster with short decumbent or appressed hairs, and long subdecumbent hairs. Minor: Head nearly subquadrate, longer than wide, narrowed anteriorly, lateral margins slightly convex, posterior margin of head nearly straight; dorsum of propodeum weakly convex, posterodorsal corner with a pair of triangular teeth; gaster with short subdecumbent to decumbent hairs and dispersed long suberect or subdecumbent hairs. Head slightly longer than wide (CI 78-92), in full-face view nearly subrectangular, about 1.2 times longer than wide. Posterior margin of head medially concave, posterolateral corners well developed, and rounded, lateral margins nearly straight. Mandibles with six teeth. Anterior margin of clypeus weakly concave in the middle, and laterally convex. Antennae with ten or eleven segments (larger major workers). Scapes short (HL 0.57-1.06, SL 0.26-0.40, SI 37-49). Ocelli present or absent. Eyes present, consisting of one to ten ommatidia (EL 0.01-0.10). Supraclypeal area triangular and well defined.
In profile view, posterolateral corner of head with (larger major workers) or without (smaller major workers) a small, obtuse tooth resembling a horn. Promesonotum high and nearly rounded, metanotal groove deeply impressed. Propodeum lower than promesonotum and about 1.8 times higher than long, dorsal face of propodeum flat, sometimes weakly concave, and declining posteriorly, propodeum armed, posterodorsal corners each armed with a laminate triangular tooth, declivity weakly concave, with thin lateral laminae. Propodeal lobes nearly rounded. Propodeal spiracle rounded and situated slightly above mid-height of sclerite by half the diameter of the spiracle, and beyond mid-length of sclerite by the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about 2.5 times the diameter of the spiracle (PSL 0.05-0.14), and distance to declivity same as the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin and sides of rounded; sides of propodeum straight.
Petiole longer than high (PTL 0.18-0.38, PTH 0.14-0.25) and with a relatively long peduncle, ventral face weakly convex in the middle. Combined outile of dorsal surface of peduncle and anterior face of node concave, posterior face of node vertical and weakly convex, anterodorsal and posterodorsal corner rounded, dorsum convex. Subpetiolar process produced as a small denticle, almost as large as the diameter of the propodeal spiracle. Postpetiolar node convex and slightly lower than petiolar node. In dorsal view, petiolar node not as broad as postpetiolar node (PTW 0.11-0.23, PPW 0.15-0.33) and petiolar node wider than long (PNL 0.07-0.15, PTW 0.11-0.23), anterior and posterior margins of petiole and postpetiole straight, sides rounded in petiole and postpetiole.
Dorsal surface of mandibles, clypeus, supraclypeal area and frons smooth and shiny, with scattered piligerous punctae on head and mandibles. Head with longitudinal and parallel rugae in direction of posterior margin of head, and rugoreticulate close to posterior margin of head. Mesosoma smooth and shiny, except for katepisternum (areolate), metapleuron (finely areolate and with longitudinal rugae), and propodeum (areolate). Petiole and ventral face of postpetiole areolate. In dorsal view, promesonotum smooth and shiny medially, as well as postpetiole and gaster; propodeum and petiole areolate.
Lateral margins of head with short decumbent or appressed hairs and long suberect hairs. Posterior margin of head with short subdecumbent hairs. Scapes with appressed hairs. Outer margin of mandible with short decumbent or appressed hairs. Mesosoma with short subdecumbent hairs and long erect or suberect hairs. Petiole and postpetiole with short decumbent hairs and long subdecumbent hairs. Tibia with decumbent to appressed hairs. Gaster with short decumbent or appressed hairs and long suberect or subdecumbent hairs. Color yellowish ferruginous.
Description of minor workers. Measurements ( Head longer than wide (CI 86-92), in full-face view nearly subquadrate, about 1.1 times longer than wide, narrowed anteriorly. Posterior margin of head nearly straight, posterolateral corners rounded, lateral margins convex. Mandibles with five teeth. Anterior margin of clypeus slightly concave, and laterally angulate. Antennae with ten segments. Scape fails to reach the posterior margin of head . Eyes present, consisting of one ommatidium (EL 0.01-0.02). Supraclypeal area triangular.
In profile, promesonotum weakly convex, metanotal groove deeply impressed. Propodeum about 1.5 times higher than long, dorsal face of propodeum nearly flat, weakly convex, and declining posteriorly, anterodorsal corner rounded, posterodorsal corners each armed with a triangular laminate tooth, declivity concave with thin lateral laminae. Propodeal lobes nearly rounded. Propodeal spiracle rounded and situated slightly above mid-height of sclerite by about half the diameter of the spiracle, and beyond mid-length of sclerite by about 1.5 times the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum almost 1.5 times the diameter of the spiracle (PSL 0.03-0.06), and distance to declivity about half the diameter of the spiracle. In dorsal view, promesonotum about 1.2 times longer than wide, anterior margin nearly rounded and sides convex, and narrowed posteriorly; sides of propodeum weakly convex.
Petiole longer than high (PTL 0.13-0.16, PTH 0.10-0.12) and with relatively short peduncle, ventral face medially convex. Combined outline of dorsal surface of peduncle and anterior face of node medially concave, posterior face of node vertical and slightly convex, anterodorsal and posterodorsal corner rounded, dorsum convex. Subpetiolar process produced as a small denticle, almost as large as the diameter of the propodeal spiracle. Postpetiolar node nearly rounded and slightly lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PTW 0.08-0.10, PPW 0.11-0.14), and petiolar node wider than long (PNL 0.06-0.08, PTW 0.08-0.10), anterior and posterior margin of petiole and postpetiole nearly straight, sides rounded in petiole and postpetiole.
Dorsal surface of head, mandibles, and clypeus smooth and shiny with scattered piligerous punctae on head and mandibles. Gena and frontal lobes with short longitudinal rugae. Mesosoma smooth and shiny, except for katepisternum, metapleuron and propodeum which are areolate. Petiole and ventral face of postpetiole areolate. In dorsal view, promesonotum, postpetiole and gaster smooth and shiny, propodeum and petiole areolate.
Lateral margins of head with short decumbent or appressed hairs posterior margin of head with subdecumbent hairs. Scapes with decumbent or appressed hairs. Outer margin of mandibles with decumbent hairs. Mesosoma with short subdecumbent hairs and long suberect hairs. Petiole and postpetiole with short appressed hairs and long subdecumbent hairs. Tibia with decumbent to appressed hairs. Gaster with abundant, short, subdecumbent to decumbent hairs and dispersed, long, suberect to subdecumbent hairs. Color yellowish ferruginous.
Distribution and biology. Carebara nosindambo is a widespread species found in the east, central and southwestern parts of Madagascar (Figure 69). Specimens were found in the following habitats: disturbed gallery, montane forest, ericoid thickets on sand, grassland, littoral forest, littoral rainforest, transition to montane forest, montane forest, montane rainforest, marsh edge, montane shrubland, park/garden, and rainforest. C. nosindambo was found at elevations ranging from 10 m to 1580 m, and specimens were collected using maxi-Winkler traps, Berlese funnels, and pitfall traps. Individuals and colonies were found in sifted litter, leaf mold, rotten wood, rotten logs, root matter of Asplenium sp. (using Berlese trap), under stones, in ground nests, sifted litter, dead tree stumps, dead twigs above ground, and leaf litter.
Comments. Carebara nosindambo can be confused with C. omasi but can be separated by the sculpture of the posterolateral portion of the cephalic dorsum, which is sculptured in C. nosindambo and lacking sculpture in C. omasi. C. nosindambo is widely distributed in the center and east of Madagascar, with one record in the southwestern part of the island, while C. omasi is present in central and southwestern parts of Madagascar. Others thirteen species were recorded at the same localities: C. bara, C. betsi, C. dota, C. grandidieri, C. hainteny, C. hiragasy, C. jajoby, C. kabosy, C. mahafaly, C. omasi, C. placida, C. raberi, and C. sampi. C. nosindambo have four intermediates in the major worker subcaste (Figure 53). The head is longer than wide, in full-face view nearly subquadrate, the posterolateral corners are rounded in intermediates 1 and 2, and slightly narrowed posteriorly in intermediates 3 and 4. The posterior margin of the head is concave in intermediates 1 and 2, and deeply concave in intemediates 3 and 4. The eyes are small and reduced to one ommatidium in intermediates 1 and 2, with up to twelve ommatidia in intermediate 4.
Ocelli are absent in intermediates 1, 2 and 3, but present and well developed in intermediate 4 (one or two ocelli). Reduced flight sclerites are present in intermediate 4. The dorsum of the mesosoma is convex anteriorly and gradually slopes to the declivity in intermediate 4, while in intermediates 1, 2 and 3, the dorsum of the mesosoma is convex and slopes anteriorly, the propodeum is below the promesonotum, the promesonotum is nearly rounded. The propodeum is armed with a pair of small triangular teeth in all intermediates. The anterior margin of the petiole in intermediate 4 is nearly straight, but concave in the center in the other intermediates. The sculpture of the head is nearly the same in all the intermediates, with parallel and longitudinal rugae, the frontal area is smooth and shiny; the sculpture of the mesosoma is also the same in all intermediates. The pilosity on the head and body follows the same pattern, except for intermediate 4, which has more abundant, short appressed hairs on the gaster.
Diagnosis. Antennae ten-segmented. Major: Head nearly subrectangular, longer than wide, lateral margins straight and parallel, posterolateral corners well developed and rounded, posterior margin of head deeply concave; dorsum of propodeum flat, posterodorsal corner with a pair of triangular teeth; gaster with very short decumbent or appressed hairs, and sparse, longer suberect hairs. Minor: Head longer than wide, posterior margin of head nearly straight; dorsum of propodeum weakly convex, posterodorsal corner with a pair of laminate, small, upwardly directed triangular teeth; gaster with short decumbent hairs and sparse, longer suberect to subdecumbent hairs.
Description Head slightly longer than wide (CI 82-89), in full-face view nearly subrectangular, about 1.2 times longer than wide. Posterior margin of head deeply concave, posterolateral corners well developed and rounded, lateral margins straight and parallel. Mandibles with six teeth. Anterior margin of clypeus nearly straight, and laterally convex. Ocelli present or absent. Antennae with ten segments. Scapes short (HL 0.62-1.10, SL 0.27-0.42, SI 0.01-0.15). Eyes present, consisting of one to 15 ommatidia (EL 0.01-0.15). Supraclypeal area triangular and well defined.
In profile view, posterolateral corner of head with a small angulate tooth resembling a horn. Promesonotum high and nearly rounded, promesonotal suture present or absent, when present, weakly impressed on dorsum, metanotal groove deeply impressed. Propodeum lower than promesonotum, and about 1.5 times higher than long, dorsal face of propodeum flat and declining posteriorly, posterodorsal corners of propodeum each armed with an acute triangular tooth, declivity concave with thin lateral laminae. Propodeal lobes triangular. Propodeal spiracle nearly oval and situated slightly above mid-height of sclerite, and beyond mid-length of sclerite by about half the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum almost 3.2 times the diameter of the spiracle (PSL 0.04-0.07), and distance to declivity about 2.2 times the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin and sides rounded, and narrowed posteriorly; sides of propodeum straight.
Petiole longer than high ) and with relatively long peduncle, ventral face weakly convex at center. Combined outline of dorsal surface of peduncle and anterior face of node nearly straight, weakly concave, posterior face of node vertical and slightly convex, anterodorsal corner weakly convex, posterodorsal corner rounded, dorsum narrow and rounded. Subpetiolar process produced as a small denticle, slightly smaller than the diameter of the propodeal spiracle. Postpetiolar node rounded and lower than petiolar node. In dorsal view, petiolar node almost as wide as postpetiolar node (PTW 0.13-0.24, PPW 0.18-0.33) and petiolar node wider than long (PNL 0.07-0.14, PTW 0.13-0.24), anterior margin of petiole weakly concave, and concave in postpetiole, posterior margin of petiole and postpetiole straight, sides rounded in petiole and postpetiole.
Dorsal surface of mandibles, clypeus and frons smooth and shiny, with scattered piligerous punctae on head and mandibles. Head with fine longitudinal rugae directed to posterior margin of head, and rugoreticulate close to posterior margin of head. Posterolateral portion of cephalic dorsum smooth and shiny. Sides of pronotum finely areolate, mesonotum and anepisternum smooth and shiny, katepisternum and metapleuron areolate-rugose. Pronotum finely areolate. Petiole, ventral face and sides of postpetiole areolate. In dorsal view, promesonotum, postpetiole and gaster smooth and shiny, propodeum and petiole areolate.
Lateral margins of head with short appressed hairs and long erect to suberect hairs, posterior margin with subdecumbent hairs. Scapes with appressed hairs. Outer margin of mandibles with short appressed hairs. Mesosoma with short suberect hairs and long erect hairs. Petiole and postpetiole with short decumbent hairs and long subdecumbent hairs. Tibia with appressed hairs. Gaster with short to very short appressed or decumbent hairs and dispersed, long suberect hairs. Color yellowish ferruginous.
In profile, promesonotum weakly convex, nearly flat, metanotal groove deeply impressed. Propodeum about 1.4 times higher than long, dorsal face of propodeum slightly convex, and declining posteriorly, propodeum armed, posterodorsal corners each armed with a laminate triangular and small tooth, declivity weakly convex, nearly flat, with thin lateral laminae. Propodeal lobes triangular. Propodeal spiracle rounded and situated above mid-height of sclerite by about 1.5 times the diameter of the spiracle, and beyond mid-length of sclerite by about two times the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum almost twice the diameter of the spiracle (PSL 0.04-0.06), and distance to declivity same as the diameter of the spiracle. In dorsal view, promesonotum about 1.1 times longer than wide, anterior margin weakly convex, sides convex and narrowed posteriorly; sides of propodeum weakly convex.
Petiole longer than high (PTL 0.12-0.15, PTH 0.10-0.13) and with relatively long peduncle, ventral face medially convex. Combined outline of dorsal surface of peduncle and anterior face of node medially concave, posterior face of node slightly convex, anterodorsal and posterodorsal corner rounded, dorsum convex. Subpetiolar process produced as a small denticle, almost the same as half the diameter of the propodeal spiracle. Postpetiolar node nearly rounded and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PTW 0.08-0.11, PPW 0.11-0.14), and petiolar node wider than long (PNL 0.06-0.08, PTW 0.08-0.11), anterior and posterior margins of petiole and postpetiole nearly straight, sides rounded in petiole and postpetiole.
Dorsal surface of head, mandibles, and clypeus smooth and shiny with scattered piligerous punctae on head and mandibles. Gena and frontal lobes with short longitudinal rugae. Mesosoma smooth and shiny except for mesopleuron and propodeum (areolate) and metapleuron (areolate-rugose). Petiole and ventral face of postpetiole areolate. In dorsal view, promesonotum, postpetiole and gaster smooth and shiny, propodeum and petiole areolate.
Lateral margins of head with decumbent hairs, posterior margin with subdecumbent hairs. Scapes with appressed hairs. Outer margin of mandibles with decumbent hairs. Mesosoma with short and long suberect hairs. Petiole and postpetiole with short appressed hairs and longer subdecumbent hairs. Tibia with appressed hairs. Gaster with short decumbent to appressed hairs and long subdecumbent hairs. Color yellowish ferruginous.
Distribution and biology. Carebara omasi was collected in the central and southwestern parts of Madagascar ( Figure 69). This species occurs in disturbed gallery montane forest, montane rainforest and Uapaca woodland, and was collected at elevations ranging from 1050 m to 1491 m. Individuals and colonies were found in rotten logs, leaf mold and rotten wood. They were collected using maxi-Winkler traps.
Comments. Carebara omasi can be confused with C. nosindambo but can be separated by the sculpture of the posterolateral portion of the cephalic dorsum, which is lacking sculpture in C. omasi and is sculptured in C. nosindambo. C. omasi is present only in central and southwestern areas of Madagascar while C. nosindambo is widespread throughout most of Madagascar. C. omasi is endemic to the center of Madagascar, but there are also records from southwestern Madagascar, other six species were recorded at the same localities: C. bara, C. betsi, C. grandidieri, C. hiragasy, C. nosindambo, and C. sampi. C. omasi have three intermediates in the major worker subcaste (Figure 56). The shape of the posterolateral corner and posterior margin of the head varies little among all intermediates. Eyes are reduced to one to four ommatidia in all intermediates, but intermediate 3 presents up to 40 ommatidia. Ocelli are absent in intermediate 1, but present and well developed in intermediates 2 and 3. Intermediates 2 and 3 have reduced flight sclerites. The dorsum of the mesosoma is convex anteriorly and gradually slopes to the declivity in intermediate 3, but in intermediates 1 and 2 the dorsum of the mesosoma is nearly rounded anteriorly, the propodeum is below the promesonotum. The propodeum is armed with a pair of triangular teeth in all intermediates. The petiole and postpetiole do not vary much in all intermediates, the combined outline of dorsal surface of peduncle and anterior face of node is slightly concave in intermediate 1 and 2, nearly straight in intermediate 3, the petiolar node is slightly thinner in intermediate 3. Pilosity is nearly the same in all intermediates, but intermediate 3 has more abundant, short appressed hairs on the gaster. The sculpture of the head and mesosoma is almost the same in all intermediates.

Carebara placida
Diagnosis. Antennae ten-segmented. Major: Head subrectangular, longer than wide, lateral margins slightly convex, posterior margin of head deeply concave; dorsum of propodeum flat, posterodorsal corner of propodeum angulate; head with longitudinal rugae. Minor: Head nearly subquadrate, slightly longer than wide; dorsum of promesonotum and propodeum weakly convex, posterodorsal corner convex; petiolar node roundly prominent; gaster with abundant short suberect hairs.  Head slightly longer than wide (CI 76-79), in full-face view nearly subrectangular, about 1.2 times longer than wide, slightly narrowed anteriorly. Posterior margin of head deeply concave, posterolateral corners rounded, lateral margins slightly convex. Mandibles with six teeth. Anterior margin of clypeus slightly concave in the middle, nearly straight, and laterally convex. Ocelli present or absent. Antennae with ten segments. Scapes short . Eyes present, consisting of fifteen to thirty ommatidia (EL 0.01-0.05). Supraclypeal area acutely triangular and well defined.
In profile view, posterolateral corner of head with a small triangular tooth resembling a horn. Promesonotum convex, (metanotum present in larger major workers), dorsum of mesonotum slightly convex, promesonotal suture present on dorsum, metanotal groove deeply impressed, propodeum lower than promesonotum, and about 1.6 times higher than long, dorsal face of propodeum slightly convex, nearly flat, and declining posteriorly; posterodorsal corners of propodeum angulate (more noticeable in larger major workers); anterodorsal corner nearly rounded; declivity concave with thin lateral laminae. Propodeal lobes convex. Propodeal spiracle rounded and situated above midheight of sclerite, and beyond mid-length of sclerite by about two times the diameter of the spiracle, (closer to mid-length and mid-height in larger major workers), distance from propodeal spiracle to posterodorsal corner of propodeum about twice the diameter of the spiracle (PSL 0.04-0.11), and distance to declivity less than half the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin and sides rounded, sides weakly convex in larger major workers; sides of propodeum convex, and straight in larger major workers.
Petiole longer than high (PTL 0.18-0.36, PTH 0.14-0.25) and with relatively long peduncle, ventral face slightly convex, nearly flat. Combined outline of dorsal surface of peduncle and anterior face of node medially concave, posterior face of node convex, anterodorsal and posterodorsal corner convex, dorsum rounded. Subpetiolar process produced as denticle, barely larger than the diameter of the propodeal spiracle. Postpetiolar node nearly rounded and slightly lower than petiolar node. In dorsal view, postpetiolar node slightly wider than petiolar node (PTW 0.12-0.24, PPW 0.17-0.29) and petiolar node wider than long (PNL 0.10-0.20, PTW 012-0.24), anterior margin of petiole convex, posterior margin straight, anterior and posterior margin of postpetiole straight, sides nearly rounded in petiole and postpetiole.
Dorsal surface of mandibles, clypeus and supraclypeal area smooth and shiny with scattered piligerous punctae on head and mandibles. Head with longitudinal rugae directed to the posterior margin, gena with well-developed and longitudinal rugae. Posterolateral portion of cephalic dorsum with longitudinal rugae, smooth and shiny on larger major workers. Mesosoma smooth and shiny, except for katepisternum and sides of propodeum (areolate) and metapleuron (finely areolate and with longitudinal rugae). Petiole and ventral face of postpetiole finely areolate. In dorsal view, mesosoma, petiole, postpetiole and gaster smooth and shiny.
Lateral margins of the head with short and long erect to suberect hairs, posterior margin with suberect hairs. Scapes with abundant decumbent hairs. Outer margin of mandibles with short decumbent and appressed hairs. Mesosoma with short and long erect to suberect hairs. Petiole and postpetiole with short subdecumbent hairs and longer suberect hairs. Tibia with decumbent hairs. Gaster with short decumbent hairs, and long suberect to subdecumbent hairs. Color yellowish ferruginous.  MLI 68; Head slightly longer than wide (CI 93-95), in full-face view nearly subquadrate, about 1.1 times longer than wide. Posterior margin of head straight, posterolateral corners rounded, lateral margins weakly convex. Mandibles with five teeth. Anterior margin of clypeus nearly straight, and laterally angulate. Antennae with ten segments. Scape fails to reach the posterior margin of head . Eyes present, consisting of one ommatidium (EL 0.01). Supraclypeal area triangular but poorly defined.
In profile, promesonotum weakly convex, nearly straight, metanotal groove deeply impressed. Propodeum about 1.2 times higher than long, dorsal face of propodeum weakly convex, declining posteriorly, posterodorsal corner unarmed (nearly convex), declivity slightly concave, nearly flat, with thin lateral laminae. Propodeal lobes convex. Propodeal spiracle rounded and situated above mid-height of sclerite, and beyond mid-length of sclerite by about two times the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum and distance to declivity same as the diameter of the spiracle (PSL 0.02-0.03). In dorsal view, promesonotum slightly longer than wide, anterior margin rounded, sides convex, narrowed posteriorly; sides of propodeum convex.
Petiole longer than high (PTL 0.13-0.14, PTH 0.11) and with relatively short peduncle, ventral face medially convex. Petiolar node thick, combined outline of dorsal surface of node and anterior face of node medially concave, posterior margin slightly convex, anterodorsal corner convex and posterodorsal corner rounded, dorsum nearly rounded. Subpetiolar process produced as a small denticle, almost the same as the diameter of the propodeal spiracle. Postpetiolar node strongly convex and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PTW 0.08-0.09, PPW 0.12-0.13), and petiolar node as wide as long (PNL 0.08-0.09, PTW 0.08-0.09), anterior margin of petiole convex, posterior margin nearly straight, anterior and posterior margins of postpetiole straight, sides convex in petiole and postpetiole.
Dorsal surface of head, mandibles and clypeus smooth and shiny with scattered piligerous punctae on head and mandibles. Gena and frontal lobes with short longitudinal rugae. Mesosoma smooth and shiny, except for katepisternum and metapleuron which are finely areolate. Petiole and ventral face of postpetiole finely areolate. In dorsal view, mesosoma, petiole, postpetiole and gaster smooth and shiny.
Lateral margins, posterior margin of head, scape and outer margin of mandible with suberect to subdecumbent hairs. Mesosoma with erect to suberect hairs. Petiole and postpetiole with short and long subdecumbent hairs. Tibia with decumbent hairs. Gaster with abundant suberect hairs. Color yellowish.
Distribution and biology. Carebara placida is known only from one locality in southeastern Madagascar (Figure 69). Individuals of this species occur in rainforest and transition to montane forest at an elevation of 600 m, and were collected under stones.
Comments. Carebara placida can be separated from other species by the next combination of characters: dorsum of head with well-defined longitudinal rugae, while others species are either unsculptured or with irregular longitudinal rugae. C. placida is known only from one locality in southeastern Madagascar. Other six species were recorded at the same locality: C. dota, C. grandidieri, C. hainteny, C. hiragasy, C. jajoby, and C. nosindambo. C. placida have two intermediates in the major worker subcaste (Figure 58). The posterolateral corner of head in intermediates slightly narrowed posteriorly. The posterior margin of the head is weakly to deeply concave in both intermediates.  -16.28322, 48.81443, 865 m, transition humid forest, 6-8.xii.2007, (B.L. Fisher et al.).  Diagnosis. Antennae ten-segmented. Major: Head nearly subrectangular, longer than wide, lateral margins nearly straight, posterior margin of head deeply concave; dorsum of propodeum nearly flat, slightly convex in the anterodorsal corner, posterodorsal corner with a pair of small triangular teeth; gaster with short decumbent hairs, and longer subdecumbent hairs. Minor: Head longer than wide, lateral margins slightly convex, posterior margin of head nearly straight; dorsum of propodeum flat and declining posteriorly, posterodorsal corner with a pair of small triangular teeth, gaster with short decumbent hairs and dispersed, longer subdecumbent hairs. Head longer than wide (CI 74-81), in full-face view nearly subrectangular, about 1.3 times longer than wide. Posterior margin of head deeply concave, posterolateral corners well developed and nearly rounded, lateral margins slightly convex, nearly straight, slightly narrowed forward. Mandibles with six teeth. Anterior margin of clypeus straight, and laterally convex. Antennae with ten segments. Scapes short (HL 0.59-1.12, SL 0.25-0.38, SI 34-46). Ocelli present or absent. Eyes present, consisting of one ommatidium (EL 0.01-0.09). Supraclypeal area triangular and well defined.
In profile, promesonotum high and nearly rounded, metanotal groove deeply impressed. Propodeum lower than promesonotum, and about 1.7 times higher than long, dorsal face of propodeum flat and declining posteriorly, propodeum armed, posterodorsal corners each armed with a triangular tooth, anterodorsal corner convex, declivity weakly concave, with thin lateral laminae. Propodeal lobes triangular. Propodeal spiracle rounded and situated above mid-height of sclerite, and beyond mid-length of sclerite by about half the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about three times the diameter of the spiracle (PSL 0.06-0.12), and distance to declivity about twice the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin and sides rounded; sides of propodeum straight.
Petiole longer than high (PTL 0.17-0.39, PTH 0.15-0.26) and with relatively short peduncle, ventral face slightly convex. Combined outline of dorsal surface of peduncle and anterior face of node slightly concave, nearly straight, posterior face of node vertical and weakly convex, anterodorsal corner convex, posterodorsal corner rounded, dorsum convex. Subpetiolar process produced as a small denticle, almost the same as the diameter of the propodeal spiracle. Postpetiolar node nearly rounded and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PTW 0.13-0.23, PPW 0.17-0.29) and petiolar node wider than long (PNL 0.08-0.14, PTW 0.13-0.23), anterior and posterior margins of petiole straight, anterior margin of postpetiole weakly concave, and weakly convex posterior margin, sides rounded in petiole and postpetiole.
Dorsal surface of mandibles, clypeus and frons smooth and shiny, with scattered piligerous punctae on head and mandibles. Head with longitudinal rugae directed toward posterior margin, rugoreticulate close to posterior margin of head. Posterolateral portion of cephalic dorsum smooth and shiny. Mesosoma smooth and shiny, except katepisternum, propodeum and metapleuron which are areolate. Petiole and ventral face of postpetiole areolate. In dorsal view, promesonotum, postpetiole and gaster smooth and shiny, propodeum and petiole areolate.
Lateral margins of head with short decumbent hairs and long suberect hairs, posterior margin with subdecumbent hairs. Scapes with appressed hairs. Outer margin of mandibles with sparse and short appressed hairs. Mesosoma with short subdecumbent hairs and long suberect hairs. Petiole with short decumbent hairs and long suberect hairs, postpetiole with short and long decumbent hairs. Tibia with appressed hairs. Gaster with short decumbent hairs and long subdecumbent hairs. Color yellowish ferruginous.
Description of minor workers. Measurements Head longer than wide (CI 87-90), in full-face view nearly subquadrate, about 1.1 times longer than wide, slightly narrowed anteriorly. Posterior margin of head nearly straight, posterolateral corners rounded, lateral margins slightly convex. Mandibles with five teeth. Anterior margin of clypeus nearly straight, and laterally angulate. Antennae with ten segments. Scape fails to reach the posterior margin of head . Eyes present, consisting of one ommatidium (EL 0.01-0.02). Supraclypeal area triangular but poorly defined.
In profile view, promesonotum weakly convex, metanotal groove deeply impressed. Propodeum about 1.5 times higher than long, dorsal face of propodeum flat and declining posteriorly, anterodorsal corner rounded, posterodorsal corners of propodeum each armed with a triangular tooth, declivity nearly flat, with thin lateral laminae. Propodeal lobes short and convex. Propodeal spiracle nearly oval and situated above midheight of sclerite by about half the diameter of the spiracle, and beyond mid-length of sclerite by about the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about 1.5 times the diameter of the spiracle (PSL 0.03-0.04), and distance to declivity same as the diameter of the spiracle. In dorsal view, promesonotum about 1.3 times longer than wide, anterior margin rounded, sides convex, narrowed posteriorly; sides of propodeum straight.
Petiole longer than high (PTL 0.14-0.16, PTH 0.10-0.12) and with relatively short peduncle, ventral face slightly convex at center. Combined outline of dorsal surface of peduncle and anterior face of node concave, posterior face of node vertical and slightly convex, anterodorsal and posterodorsal corner rounded, dorsum convex. Subpetiolar process produced as a small denticle, slightly smaller than the diameter of the propodeal spiracle. Postpetiolar node nearly rounded and slightly lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PTW 0.09-0.10, PPW 0.12-0.13), and petiolar node wider than long (PNL 0.07-0.08, PTW 0.09-0.10), anterior and posterior margins of petiole weakly convex, anterior margin of postpetiole convex, and posterior margin concave, sides nearly rounded in petiole and postpetiole.
Dorsal surface of head, mandible and clypeus smooth and shiny with scattered piligerous punctae on head and mandibles. Gena and frontal lobes with short longitudinal rugae. Mesosoma smooth and shiny, except for katepisternum, propodeum and metapleuron which are areolate. Petiole and ventral face of postpetiole areolate. In dorsal view, promesonotum, postpetiole and gaster smooth and shiny, propodeum and petiole areolate.
Lateral margins of head with short decumbent hairs, posterior margin with suberect hairs. Scapes and outer margin of mandibles with decumbent hairs. Mesosoma with short and long suberect to subdecumbent hairs. Petiole and postpetiole with short decumbent hairs and longer subdecumbent hairs. Tibia with decumbent hairs. Gaster with short decumbent to appressed hairs, and long subdecumbent hairs. Color yellowish ferruginous.
Distribution and biology. Carebara raberi is known from only one locality, in northeastern Madagascar, and only one locality ( Figure 69). This species was found in the rainforest, at the transition between humid forest, and tropical dry forest, at 865 m, taken from sifted litter, rotten logs, and leaf mold. Individuals were collected using maxi-Winkler traps.
Comments. Carebara raberi can be confused with C. sampi and C. lova but can be separated by the hair pilosity at the dorsum of the gaster, which is abundant in C. raberi, while in C. sampi and C. lova are fewer. C. raberi is known only from one locality in northeastern Madagascar, while C. sampi was recorded from south and southwestern Madagascar, and C. lova is known from the northwestern of Madagascar. C. raberi is the only species of Carebara recorded at this area.
Diagnosis. Antennae ten-segmented. Major: Head nearly subrectangular, longer than wide, narrowed anteriorly, lateral margins of head convex; dorsum of propodeum nearly flat, posterodorsal corner with a pair of small triangular teeth; combined outline of dorsal surface of peduncle and anterior face of node concave, posterior face vertical and straight; gaster with abundant, short decumbent hairs, and long subdecumbent hairs. Minor: Head nearly subquadrate, slightly longer than wide, narrowed anteriorly, posterior margin of head nearly straight; dorsum of propodeum nearly flat, propodeum armed with a pair of short triangular teeth; combined outline of dorsal surface of peduncle and anterior face of node concave, posterior face convex; gaster with abundant, short decumbent hairs, and sparse, long subdecumbent hairs.
Description Head longer than wide (CI 84), in full-face view nearly subrectangular, about 1.2 times longer tan wide, slightly narrowed anteriorly. Posterior margin of head medially concave, posterolateral corners rounded, lateral margins convex. Mandibles with six teeth. Anterior margin of clypeus slightly concave in the middle, nearly straight, and laterally convex. Antennae with ten segments. Scapes short (HL 0.55. SL 0.24, SI 44). Ocelli absent. Eyes present, consisiting of three ommatidia (EL 0.02). Supraclypeal area with a longitudinal strip, barely surpassing frontal carina.
In profile view, posterolateral corner of head with a small angulate tooth resembling a horn. Promesonotum high and convex, metanotal groove deeply impressed. Propodeum lower than promesonotum, and about 1.5 times higher than long, dorsal face of propodeum flat and declining posteriorly, posterodorsal corners of propodeum each armed with a triangular tooth, anterodorsal corner convex, declivity of propodeum concave with thin lateral laminae. Propodeal lobes triangular. Propodeal spiracle rounded and situated slightly above mid-height of sclerite by about less tan half the diameter of the spiracle, and beyond mid-length of sclerite by about the diameter of the spiracle, distance from propodeal spiracle to posterodrosal corner of propodeum about 1.8 times the diameter of the spiracle (PSL 0.05), and distance to declivity about 0.5 times the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin and sides rounded; sides of propodeum weakly convex.
Petiole longer than high (PTL 0.18, PTH 0.14) and with relatively long peduncle, ventral face weakly convex in the middle. Combined outline of dorsal surface of peduncle and anterior face of node concave, posterior face of node vertical and straight, anterodorsal corner convex, posterodorsal corner rounded, dorsum nearly rounded. Subpetiolar process produced as a small denticle, slightly smaller than the diameter of the propodeal spiracle. Postpetiolar node convex and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PTW 0.13, PPW 0.17) and petiolar node wider than long (PNL 0.09, PTW 0.13), anterior margin of petiole convex, posterior margin weakly concave, anterior and posterior margins of postpetiole straight, sides rounded in petiole and postpetiole.
Dorsal surface of mandibles, clypeus and frons smooth and shiny with scattered piligerous punctae on head and mandibles. Head with finely longitudinal rugae except for middle area of head, rugoreticulate close to posterior margin of head. Posterolateral portion of cephalic dorsum smooth and shiny. Mesosoma smooth and shiny, except for katepisternum and propodeum (areolate), and metapleuron (areolate and with longitudinal rugae). Petiole and ventral face of postpetiole areolate. In dorsal view, promesonotum, postpetiole and gaster smooth and shiny; propodeum and petiole areolate.
Lateral margins of head with short decumbent hairs and long subdecumbent hairs. Scapes with appressed hairs. Outer margin of mandibles with sparse and short appressed hairs. Mesosoma with short and long suberect hairs. Petiole and postpetiole with short decumbent hairs and long subdecumbent hairs. Tibia with appressed hairs. Gaster with abundant, short decumbent hairs, and sparse, long subdecumbent hairs. Color yellowish ferruginous. Head longer than wide (CI 85-92), in full-face view nearly subquadrate, about 1.1 times longer than wide, narrowed anteriorly. Posterior margin of head nearly straight, weakly concave, posterolateral corners rounded, lateral margins convex. Mandibles with five teeth. Anterior margin of clypeus nearly straight, and laterally angulate, almost triangular. Antennae with ten segments. Scape fails to reach the posterior margin of head (HL 0.34-0.38, SL 0.21-0.24, SI 61-67). Eyes present, consisting of one ommatidium (EL 0.01). Supraclypeal area triangular but not well defined.
In profile view, promesonotum weakly convex, metanotal groove deeply impressed. Propodeum about 1.2 times higher than long, dorsal face of propodeum nearly flat, and barely declining posteriorly, posterodorsal corner usually unarmed but when armed, posterodorsal corners each armed with a small triangular tooth, declivity nearly flat with thin lateral laminae. Propodeal lobes triangular. Propodeal spiracle nearly oval and situated above mid-height of sclerite, and beyond mid-length of sclerite by about half the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about twice the diameter of the spiracle (PSL 0.02-0.04), and distance to declivity same as the diameter of the spiracle. In dorsal view, promesonotum about 1.1 times longer than wide, anterior margin and sides rounded, narrowed posteriorly; sides of propodeum flat.
Petiole longer than high (PTL 0.13-0.14, PTH 0.10-0.11) and with relatively short peduncle, ventral face convex. Combined outline of dorsal surface of peduncle and anterior face of node concave, posterior face of node convex, anterodorsal and posterodorsal corner rounded, dorsum nearly rounded. Subpetiolar process produced as a small denticle. Postpetiolar node convex and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PTW 0.07-0.09, PPW 0.11-0.12), and petiolar node as wide as long (PNL 0.07-0.08, PTW 0.07-0.09), anterior and posterior margins of petiole convex, and weakly concave in postpetiole, sides convex in petiole and rounded in postpetiole.
Lateral margins and posterior margin of head with subdecumbent hairs. Scapes with abundant decumbent to subdecumbent hairs. Outer margin of mandibles with few decumbent hairs. Mesosoma with short and long suberect hairs. Petiole and postpetiole with short decumbent hairs and long subdecumbent hairs. Tibia with decumbent hairs. Gaster with short decumbent to appressed hairs and long suberect to subdecumbent hairs. Color yellowish ferruginous.
Distribution and biology. Carebara salegi is known only from the north of Madagascar ( Figure 69) and occurs in the littoral rainforest, at an elevation of 90 m. Specimens were collected using maxi-Winkler traps and found in leaf litter, leaf mold and rotten wood.
Comments. Carebara salegi is endemic to the north of Madagascar, and only one major worker of this species has been collected. Other six species were recorded at the same area: C. bara, C. berivelo, C. grandidieri, C. kabosy, C. malagasy, and C. tana.
C. salegi may be confused with C. mahafaly because of the form of the head. However, the posterior margin of the head of C. mahafaly is more concave than C. salegi, and the lateral margins of the head of C. mahafaly are more convex. The promesonotum is nearly rounded in C. mahafaly and convex in C. salegi. The posterodorsal corners of propodeum in C. mahafaly have a pair of triangular teeth directed slightly upward. In C. salegi the propodeum is armed with a pair of small triangular teeth that are not directed upward. The anterodorsal corner of the petiole in C. mahafaly is nearly rounded while C. salegi is convex. The gaster has short appressed hairs in C. mahafaly, and short decumbent hairs in C. salegi. In the workers, the main difference between these two species is the form of the propodeum, which is similar to the major worker subcaste.
C. salegi does not have intermediates in the major worker subcaste.  In profile view, posterolateral corner of head with a small angulate tooth resembling a horn. Promesonotum high and nearly rounded, metanotal groove deeply impressed. Propodeum lower than promesonotum, and about 1.4 times higher than long, dorsal face of propodeum flat and declining posteriorly, posterodorsal corners of propodeum each armed with a small triangular tooth, declivity concave, nearly flat with thin lateral laminae. Propodeal lobes convex. Propodeal spiracle nearly oval and situated above mid-height of sclerite, and beyond mid-length of sclerite by about half the diameter of the spiracle, (close to mid-height and mid-length in larger major workers), distance from propodeal spiracle to posterodorsal corner of propodeum about twice the diameter of the spiracle (PSL 0.05-0.11), and distance to declivity same as the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior and posterior margins, as well as sides rounded; sides of propodeum straight.

Carebara sampi
Petiole longer than high (PTL 0.19-0.32, PTH 0.14-0.24) and with relatively long peduncle, ventral face weakly convex in the middle. Combined outline of dorsal surface of peduncle and anterior face of node slightly concave, posterior face of node vertical and weakly concave, anterodorsal corner convex, posterodorsal corner rounded, dorsum nearly rounded. Subpetiolar process produced as a small denticle, almost as large as the diameter of the propodeal spiracle. Postpetiolar node rounded and slightly lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PTW 0.12-0.22, PPW 0.18-0.32) and petiolar node wider than long (PNL 0.09-0.14, PTW 0.12-0.22), anterior and posterior margins of petiole and postpetiole nearly straight, sides of petiole and postpetiole nearly rounded.
Dorsal surface of mandibles, clypeus and frons smooth and shiny with scattered piligerous punctae on head and mandibles. Head with longitudinal rugae directed to posterolateral corners of head, transverse rugae, and reticulate on median area of posterior margin of head, followed by short longitudinal rugae. Mesosoma smooth and shiny, except for katepisternum and propodeum (areolate), and metapleuron (areolate-rugose and with longitudinal rugae). Petiole, ventral face and sides of postpetiole areolate. In dorsal view, promesonotum, postpetiole and gaster smooth and shiny; propodeum and petiole areolate.
Lateral margins of head with short appressed hairs and long suberect hairs. Scapes with appressed hairs. Outer margin of mandibles with short and sparse appressed hairs. Mesosoma with short subdecumbent hairs and long suberect hairs. Petiole and postpetiole with short decumbent or appressed hairs and long subdecumbent hairs. Tibia with appressed hairs. Gaster with short appressed hairs and long suberect or subdecumbent hairs. Color yellowish ferruginous. Head longer than wide (CI 83-91), in full-face view nearly subquadrate, about 1.1 times longer than wide, narrowed anteriorly. Posterior margin of head nearly straight, weakly concave, posterolateral corners rounded, lateral margins convex. Mandibles with five teeth. Anterior margin of clypeus concave, and laterally angulate, almost triangular. Antennae with ten segments. Scape fails to reach posterior margin of head . Eyes present, consisting of two ommatidia (EL 0.01-0.02). Supraclypeal area short and triangular, but poorly defined.
In profile, promesonotum weakly convex, nearly flat, metanotal groove deeply impressed. Propodeum 1.3 times higher than long, dorsal face of propodeum flat and barely declining posteriorly, posterodorsal corners of propodeum each armed with a triangular tooth, anterodorsal corner rounded, declivity concave with thin lateral laminae. Propodeal lobes convex. Propodeal spiracle rounded and situated above midheight of sclerite by about half the diameter of the spiracle, and beyond mid-length of sclerite by about two times the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about twice the diameter of the spiracle (PSL 0.03-0.05), and distance to declivity about 0.5 times the diameter of the spiracle. In dorsal view, promesonotum almost as longer as wide, anterior margin rounded, sides convex and narrowed posteriorly; sides of propodeum convex.
Petiole longer than high (PTL 0.11-0.15, PTH 0.09-0.12) and with relatively long peduncle, ventral face medially convex. Combined outline of dorsal surface of peduncle and anterior face of node slightly concave in the middle, nearly straight, posterior face of node convex, anterodorsal and posterodorsal corner rounded, dorsum nearly rounded. Subpetiolar process produced as a small denticle, almost as large as the diameter of the propodeal spiracle. Postpetiolar node convex and slightly lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PTW 0.08-0.10, PPW 0.10-0.14), and petiolar node slightly wider than long (PNL 0.06-0.08, PTW 0.08-0.10), anterior and posterior margins of petiole weakly convex, and straight in postpetiole, sides rounded in petiole and postpetiole.
Lateral margins of head and scape with decumbent hairs. Outer margin of mandibles with appressed hairs. Mesosoma with short subdecumbent and decumbent hairs and long suberect hairs. Petiole and postpetiole with short decumbent hairs and long subdecumbent hairs. Tibia with appressed hairs. Gaster with short decumbent or appressed hairs and long suberect or subdecumbent hairs. Color yellowish ferruginous.
Distribution and biology. Carebara sampi is known from south and southwestern Madagascar ( Figure 69) where it was found in gallery forest, tropical dry forest, and gallery forest on sandy soil, at elevations ranging from 20 m to 525 m. This species was found in the following microhabitats: rotten logs, leaf mold, rotten wood, and in semideciduous vegetation. Specimens were collected using maxi-Winkler traps.
Comments. Carebara sampi can be confused with C. lova but can be separated by the distance from the posterior border of propodeal spiracle to declivity, which is less than two times the diameter of the spiracle in C. sampi, while is same as or less than the diamater of the spiracle in C. lova. C. sampi is distributed from south and southwestern Madagascar, while C. lova is located in the northwestern of Madagascar. Other five species were recorded at the same area: C. bara, C. dota, C. grandidieri, C. hiragasy, and C. omasi.
Diagnosis. Antennae ten-segmented. Major: Head subrectangular, longer than wide, lateral margins straight and parallel, posterolateral corners rounded, posterior margin of head concave; dorsum of propodeum flat and declining posteriorly, posterodorsal corner with a pair of triangular teeth; gaster with short decumbent hairs and sparse and longer subdecumbent hairs. Minor: Head nearly subquadrate, slightly longer than wide, lateral margins weakly convex, posterior margin weakly convex; dorsum of propodeum nearly flat, posterodorsal corner with a pair of small triangular teeth; gaster with abundant decumbent hairs and sparse suberect to subdecumbent hairs.
In profile view, promesonotum high and nearly rounded, metanotal groove deeply impressed. Propodeum lower than promesonotum, and about 1.7 times higher than long, dorsal face of propodeum flat and declining posteriorly, posterodorsal corners of propodeum each armed with a triangular tooth, declivity concave, nearly flat, with thin lateral laminae. Propodeal lobes triangular. Propodeal spiracle rounded and situated slightly above mid-height of sclerite by about half the diameter of the spiracle, and beyond mid-length of sclerite by about the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about 2.5 times the diameter of the spiracle (PSL 0.05-0.07), and distance to declivity same as the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin and sides rounded, slightly narrowed posteriorly; sides of propodeum straight.
Petiole longer than high (PTL 0.20-0.24, PTH 0.14-0.16) and with relatively long peduncle, ventral face weakly convex at center. Combined outline of dorsal surface of peduncle and anterior face of node concave, posterior face of node weakly convex, anterodorsal corner convex, posterodorsal corner rounded, dorsum convex. Subpetiolar process produced as a small denticle, almost as large as the diameter of the propodeal spiracle. Postpetiolar node convex and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PTW 0.13-0.15, PPW 0.16-0.18) and petiolar node wider than long (PNL 0.11-0.12, PTW 0.13-0.15), anterior margin of petiole convex, posterior margin weakly concave, anterior and posterior margins of postpetiole straight, sides of petiole rounded, and sides of postpetiole narrowed posteriorly and convex.
Dorsal surface of mandibles, clypeus and frons smooth and shiny with scattered piligerous punctae on head and mandibles. Head with longitudinal and parallel rugae, these joining near posterior margin of head, transverse rugae along posterior margin of head. Posterolateral portion of cephalic dorsum with longitudinal rugae. Mesosoma smooth and shiny, except for katepisternum (areolate), metapleuron (rugose and with longitudinal rugae), and dorsum of propodeum (finely areolate). Petiole and ventral face of postpetiole (areolate). In dorsal view, promesonotum, petiole, postpetiole and gaster smooth and shiny.
Lateral margins of head with short decumbent hairs and long suberect hairs, posterior margin with subdecumbent hairs. Scapes with decumbent hairs. Outer margin of mandibles with short appressed hairs. Mesosoma with short and long subdecumbent hairs. Petiole, and postpetiole with short decumbent hairs and long subdecumbent hairs. Tibia with appressed hairs. Gaster with short decumbent hairs and long subdecumbent or suberect hairs. Color yellowish ferruginous.
Description of minor workers. Measurements ( Head slightly longer than wide (CI 86-89), in full-face view nearly subquadrate, about 1.1 times longer than wide. Posterior margin of head slightly concave, posterolateral corners rounded, lateral margins weakly convex. Mandibles with five teeth. Anterior margin of clypeus slightly concave in the middle, and laterally angulate. Antennae with ten segments. Scape fails to reach posterior margin of head (HL 0.35-0.38, SL 0.21-0.23, SI 57-63). Eyes present, consisting of one ommatidium (EL 0.01). Supraclypeal area triangular but not well defined.
In profile view, promesonotum weakly convex, metanotal groove deeply impressed. Propodeum about 1.1 times higher than long, dorsal face of propodeum slightly concave in the middle, nearly flat, declining posteriorly, posterodorsal corners each armed with a triangular tooth, anterodorsal corner rounded and higher than posterodorsal corner of promesonotum, declivity concave with thin lateral laminae. Propodeal lobes triangular. Propodeal spiracle rounded and situated above mid-height of sclerite by about the diameter of the spiracle, and beyond mid-length of sclerite by about two times the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about 2.5 times the diameter of the spiracle (PSL 0.03-0.04), and distance to declivity almost half the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin rounded, sides convex, narrowed posteriorly; sides of propodeum straight.
Petiole longer than high (PTL 0.12-0.15, PTH 0.10-0.11) and with a short peduncle, ventral face convex at center. Combined outine of dorsal surface of peduncle and anterior face of node slightly concave, posterior face of node vertical and slightly convex, anterodorsal corner convex, posterodorsal corner rounded, dorsum convex. Subpetiolar process produced as a small denticle. Postpetiolar node nearly rounded and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PTW 0.07-0.08, PPW 0.10-0.13), and petiolar node almost as broad as long (PNL 0.06-0.07, PTW 0.07-0.08), anterior and posterior margins of petiole convex, anterior and posterior margins of postpetiole straight, sides rounded in petiole and postpetiole.
Head, mandible and clypeus smooth and shiny with scattered piligerous punctae on head and mandibles. Gena and frontal lobes with short longitudinal rugae. Meso- Head longer than wide (78), in full-face view weakly subrectangular, about 1.2 times longer than wide. Posterior margin of head medially concave, posterolateral corners rounded, lateral margins straight or weakly convex. Mandibles with five teeth. Anterior margin of clypeus nearly straight, and weakly convex laterally. Antennae with ten segments. Scapes short (HL 0.62, SL 0.28, SI 45) barely reaching cephalic midlength. Ocelli absent. Eyes present and short, consisting of only ommatidia (EL 0.02). Supraclypeal area short and triangular, not surpassing frontal carina.
In profile view, promesonotum high and convex, metanotal groove present and not deeply impressed. Propodeum lower than promesonotum, and about 1.3 times higher than long, dorsal face of propodeum flat and declining posteriorly, posterodorsal corners of propodeum unarmed, nearly angulate, declivity weakly convex, nearly flat. Propodeal lobes short and convex. Propodeal spiracle rounded and situated slightly above mid-height of sclerite, and beyond mid-length of sclerite by about half the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about same as the diameter of the spiracle (PSL 0.06), and distance to declivity less than the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin and sides rounded, slightly narrowed posteriorly; sides of propodeum nearly convex.
Petiole weakly longer than high (PTL 0.21, PTH 0.17) and with relatively short peduncle, ventral face weakly convex at center. Combined outline of dorsal surface of peduncle and anterior face of node straigth, posterior face of node weakly concave, anterodorsal corner convex, posterodorsal corner rounded, dorsum convex. Subpetiolar process produced as a small denticle, shorter than the diameter of the propodeal spiracle. Postpetiolar node weakly rounded and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PTW 0.15, PPW 0.20) and petiolar node wider than long (PNL 0.09, PTW 0.15), anterior margin of petiole and postpetiole nearly straight, sides of petiole and postpetiole rounded.
Dorsal surface of mandibles, clypeus and median area of head smooth and shiny, with scattered piligerous punctae on head and mandibles. Head with longitudinal and parallel rugae, these joining near posterior margin of head, transverse rugae along posterior margin of head. Posterolateral portion of cephalic dorsum smooth and shiny. Mesosoma smooth and shiny, except for katepisternum (areolate), metapleuron (rugose and with longitudinal rugae), and anterior side of pronottum finely punctate. Petiole and ventral face of postpetiole (areolate). In dorsal view, mesosoma, petiole, postpetiole and gaster smooth and shiny.
Lateral and posterior margin of head with suberect to subdecumbent hairs. Scapes with decumbent hairs. Outer margin of mandibles with few and short appressed hairs. Mesosoma with short and long erect to subdecumbent hairs. Petiole and postpetiole with short decumbent hairs and long subdecumbent hairs. Tibia with appressed hairs. Gaster with abundant subdecumbent hairs. Color yellowish ferruginous.
Description of minor workers. Measurements ( Head slightly longer than wide (CI 85), in full-face view nearly subquadrate, about 1.1 times longer than wide. Posterior margin of head slightly concave, posterolateral corners convex, lateral margins weakly convex. Mandibles with five teeth. Anterior margin of clypeus slightly straight, and laterally convex. Antennae with ten segments. Scape fails to reach posterior margin of head (HL 0.40, SL 0.23, SI 58). Eyes present, consisting of one ommatidium (EL 0.02). Supraclypeal area triangular but not well defined.
In profile view, promesonotum weakly convex, metanotal groove not well impressed. Propodeum about 1.2 times higher than long, dorsal face of propodeum slight-ly convex, declining posteriorly, posterodorsal corners unarmed or angulate, declivity nearly straight. Propodeal lobes short and convex. Propodeal spiracle rounded and situated above mid-height of sclerite, and beyond mid-length of sclerite by about half the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about the same as the diameter of the spiracle (PSL 0.03), and distance to declivity almost less than the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin rounded, sides nearly rounded, narrowed posteriorly; sides of propodeum straight.
Petiole weakly longer than high (PTL 0.13, PTH 0.12) and with a short peduncle, ventral face convex at center. Combined outine of dorsal surface of peduncle and anterior face of node straight, posterior face of node vertical and slightly concave, anterodorsal and posterodorsal corner rounded, dorsum convex. Subpetiolar process produced as a small denticle, same as the diameter of the propodeal spiracle. Postpetiolar node nearly rounded and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PTW 0.09, PPW 0.13), and petiolar node wider than long (PNL 0.07, PTW 0.09), anterior and posterior margins of petiole and postpetiole straight, sides rounded in petiole and postpetiole.
Head, mandible and clypeus smooth and shiny with scattered piligerous punctae on head and mandibles. Gena and frontal lobes with short longitudinal rugae. Mesosoma smooth and shiny, except for katepisternum (areolate), and metapleuron (finely areolate combined with longitudinal rugae). Petiole and ventral face of postpetiole areolate. In dorsal view, mesosoma, petiole, postpetiole and gaster smooth and shiny.
Lateral margins, posterior margin of head and outer margin of mandibles with short decumbent hairs. Scapes with abundant subdecumbent hairs. Mesosoma with short and long suberect to subdecumbent hairs. Petiole and postpetiole with short and long decumbent hairs. Tibia with appressed hairs. Gaster with abundant suberect to subdecumbent hairs. Color yellowish ferruginous.
Distribution and biology. Carebara tanana is known only from the center of Madagascar ( Figure 69). This species was found in the savannah grassland, at an elevation of 1984 m, in leaf mold and rotten wood. This species was collected using maxi-Winkler traps.
Comments. Carebara tanana can be confused with C. tana due to the form of the head. However, the two can be separated easily by the following combination of characters: in profile view, posterodorsal corner of propodeum of C. tana armed and unarmed in C. tanana; gaster with short and long and abundant suberect to subdecumbent hairs in C. tanana, while in C. tana the major worker has the gaster with short decumbent hairs and long subdecumbent or suberect hairs, and the minor worker with abundant subdecumbent and decumbent hairs, and sparse suberect hairs. Additional to this, C. tanana is known only from the center of Madagascar, while C. tana is known from the north of Madagascar. Only other two species were collected at the same area: C. grandidieri, and C. nosindambo.
C. tanana does not have intermediates in the major worker subcaste. straight, and laterally convex. Antennae with ten segments. Scapes short (HL 0.64-1.02, SL 0.26-0.35, SI 34-42). Ocelli present or absent. Eyes present, consisting of one to twenty ommatidia (EL 0.01-0.05). Supraclypeal area triangular and well defined. In profile view, posterolateral corner of head with an angulate and triangular tooth resembling a horn. Promesonotum high and nearly rounded. Promesonotal suture present or absent on dorsum, mesonotum absent or present, metanotal groove deeply impressed. Propodeum lower than promesonotum, about 1.5 times higher than long, dorsal face of propodeum flat and declining posteriorly, anterodorsal corner rounded, posterodorsal corners each armed with a triangular tooth, declivity concave with thin lateral laminae. Propodeal lobes convex. Propodeal spiracle rounded and situated slightly above mid-height of sclerite, and beyond mid-length of sclerite by about half the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about twice the diameter of the spiracle (PSL 0.05-0.10), and distance to declivity about 1.3 times the diameter of the spiracle. In dorsal view, promesonotum about as long as wide, anterior margin and sides rounded, narrowed posteriorly; sides of propodeum straight.
Petiole longer than high (PTL 0.18-0.36, PTH 0.15-0.25) and with relatively long peduncle, ventral face slightly convex in the middle. Combined outline of dorsal surface of peduncle and anterior face of node concave at center, posterior face of node vertical and straight, anterodorsal corner convex, posterodorsal corner rounded, and dorsum nearly rounded. Subpetiolar process produced as a small denticle, almost same as the diameter of the propodeal spiracle. Postpetiolar node convex and lower than petiolar node. In dorsal view, petiolar node almost as wide as postpetiolar node (PTW 0.14-0.23, PPW 0.17-0.28) and petiolar node wider than long (PNL 0.09-0.14, PTW 0.14-0.23), anterior and posterior margins of petiole and postpetiole almost straight, sides of petiole and postpetiole rounded.
Dorsal surface of mandibles, clypeus and frons smooth and shiny with scattered piligerous punctae on head and mandibles. Head with longitudinal and parallel rugae directed to posterior margin of head. Mesosoma smooth and shiny, except for katepisternum and propodeum (areolate), metapleuron (finely areolate and with longitudinal rugae), and sides of pronotum (finely longitudinal rugulose). Petiole, ventral face and sides of postpetiole areolate. In dorsal view, median area of promesonotum smooth and shiny, as well as postpetiole and gaster. Propodeum and petiole weakly sculptured in smaller major workers and smooth and shiny in larger major workers.
Lateral margins of the head with short appressed hairs and long erect to suberect hairs, posterior margin with subdecumbent hairs. Scapes with appressed hairs. Outer margin of mandibles with sparse and short appressed hairs. Mesosoma with short and long erect and suberect hairs. Petiole and postpetiole with short decumbent hairs and long subdecumbent hairs. Tibia with appressed hairs. Gaster with short decumbent hairs and long suberect to subdecumbent hairs. Color yellowish ferruginous.
Head longer than wide (CI 86-89), in full-face view nearly subrectangular, about 1.2 times longer than wide. Posterior margin of head nearly straight, weakly concave, posterolateral corners rounded, lateral margins convex. Mandibles with five teeth. Anterior margin of clypeus nearly straight, and laterally convex. Antennae with ten segments. Scape fails to reach posterior margin of head . Eyes present, consisting of one ommatidium (EL 0.01-0.02). Supraclypeal area short and triangular.
In profile view, promesonotum weakly convex, nearly flat, metanotal groove present. Propodeum about 1.3 times higher than long, dorsal face of propodeum nearly flat and declining posteriorly, anterodorsal corner rounded, posterodorsal corners each armed with a small triangular tooth, declivity concave with thin lateral laminae. Propodeal lobes convex. Propodeal spiracle small, rounded, and situated above mid-height of sclerite, and beyond mid-length of sclerite by about half the diameter of the spiracle, distance from propodeal spiracle to posterodorsal corner of propodeum about 2.2 times the diameter of the spiracle (PSL 0.02-0.04), and distance to declivity same as the diameter of the spiracle. In dorsal view, promesonotum about 1.1 times longer than wide, anterior margin rounded, sides convex and narrowed posteriorly; sides of propodeum straight.
Petiole longer than high (PTL 0.12-0.14, PTH 0.09-0.11) and with relatively short peduncle, ventral face convex at center. Combined outline of dorsal surface of peduncle and anterior face of node concave, posterior face of node vertical and slightly convex, anterodorsal and posterodorsal corner convex, dorsum rounded. Subpetiolar process produced as a small denticle, almost as large as the diameter of the propodeal spiracle. Postpetiolar node convex and lower than petiolar node. In dorsal view, postpetiolar node wider than petiolar node (PTW 0.07-09, PPW 0.10-0.12), and petiolar node wider than long (PNL 0.06-0.07, PTW 0.07-0.09), anterior and posterior margins of petiole and postpetiole nearly straight, sides nearly rounded in petiole and postpetiole.
Dorsal surface of head, mandibles and clypeus smooth and shiny with scattered piligerous punctae on head and mandibles. Gena and frontal lobes with longitudinal rugae. Mesosoma smooth and shiny, except for katepisternum and propodeum (areolate), and metapleuron (longitudinally areolate-rugose). Petiole and ventral face of postpetiole areolate-rugose. In dorsal view, promesonotum, postpetiole and gaster smooth and shiny; propodeum and petiole areolate.  Lateral margins and posterior margin of head with short decumbent hairs. Scapes with appressed hairs. Outer margin of mandible with sparse appressed hairs. Mesosoma with short and long suberect hairs. Petiole and postpetiole with short appressed hairs and long subdecumbent hairs. Tibia with appressed hairs. Gaster with short decumbent to appressed hairs and long subdecumbent hairs. Color yellowish ferruginous.
Distribution and biology. Carebara vazimba is known from the north of Madagascar ( Figure 69). This species was found in littoral rainforest and rainforest at 10 m and 240 m, respectively. Individuals of C. vazimba were found in rotten logs, leaf mold, and rotten wood. Specimens were collected using maxi-Winkler traps.
Comments. Carebara vazimba can be confused with C. kabosy but can be separated by the length of the propodeal tooth, which is shorter than propodeal spiracle diameter in C. vazimba and slightly longer in C. kabosy. C. vazimba is distributed in the north of Madagascar, while C. kabosy is distributed in the north, northeastern and nortwestern areas of Madagascar. Other five species were collected at the same localities: C. bara, C. berivelo, C. grandidieri, C. jajoby, and C. kabosy.
C. vazimba have three intermediates in the major worker subcaste ( Figure 67). The posterolateral corner of head in intermediate 1 is slightly narrowed posteriorly, the posterior margin of the head is medially concave in all intermediates. Eyes are small and reduced to one ommatidium in intermediate 1 but intermediate 3 has eyes made up of one to twelve ommatidia. Ocelli are absent in intermediates 1 and 2, but present in intermediate 3 (one ocellus). Reduced flight sclerites are present in intermediate 3, and absent in intermediates 1 and 2. The promesonotum is nearly rounded in intermediates 1 and 2, and strongly convex in intermediate 3. The dorsum of the mesosoma is convex anteriorly and gradually slopes to the declivity in intermediate 3, while in intermediates 1 and 2 the dorsum of the mesosoma is convex anteriorly, propodeum below the promesonotum. There is no variation in the form of the petiole. The sculpture of the head of intermediate 3 is more striking than that of intermediates 1 and 2, where rugae on the head are more finely marked and the frontal area is smooth and shiny. Pilosity on the head and body follows the same pattern in all intermediates.