Research Article |
Corresponding author: Sebastian Salata ( sdsalata@gmail.com ) Academic editor: Brian Lee Fisher
© 2018 Sebastian Salata, Lech Borowiec.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Salata S, Borowiec L (2018) A new species of the ant genus Lasius Fabricius, 1804 from Crete (Hymenoptera, Formicidae). ZooKeys 789: 139-159. https://doi.org/10.3897/zookeys.789.27022
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Lasius tapinomoides sp. n. from Crete, Greece, is described and illustrated. It belongs to L. turcicus complex and is well characterized by very small body, extremely shallow metanotal groove and presence of suberect to erect setae on the apical part of scape. New records of Cretan members of the genus Lasius Fabricius, 1804 are provided, their checklist is updated, and the key to their determination is presented.
Endemic species, Greece, Lasius , Mediterranean
The genus Lasius Fabricius, 1804 is widely distributed throughout the Holarctic. Within its range, it is one of the most abundant of all Formicidae genera and its species are very often dominants of local myrmecofauna (
Crete, as one of the largest Mediterranean islands, with very diverse, mountainous landscape (
Ants were sampled between 2007 and 2014 from sites in different parts of Crete. The method was direct sampling (hand collecting). Individual specimens and nests were collected on the ground, in leaf litter and rock rubble, under stones and tree trunks. All specimens were preserved in 75% EtOH. Study was supported with material deposited in the Natural History Museum of Crete (Iraklion, Greece).
Examined specimens are housed in the following collections:
Specimens were compared using standard methods of comparative morphology. Photos were taken using a Nikon SMZ 1500 stereomicroscope, Nikon D5200 photo camera, and Helicon Focus software.
All given label data are in original spelling, presented in quotation marks; a slash (/) separates data on different rows and double slash (//) separate labels.
Specimens of Lasius tapinomoides sp. n. were compared with all other known Cretan species of the genus Lasius and type material of members of the Lasius alienus group listed below. Type specimens photographs of the Lasius alienus group members are available online on AntWeb (www.AntWeb.org) and are accessible using the unique CASENT or FOCOL identifying specimen code. Moreover, we compared them with samples of members of the Lasius alienus group from other Greek regions. Data concerning distribution of Greek Lasius samples used in the comparison is provided in series of regional checklists (
We decided to list all other ant species collected from the same localities where the new species has been found. In our opinion it provides valuable information about ecosystem structure and species diversity characteristic for habitats preferred by this species. Distribution maps of all recorded Lasius species were created in DivaGis 7.5 (
Measurements:
EL eye length; measured along the maximum vertical diameter of eye;
EW eye width; measured along the maximum horizontal diameter of eye;
HL head length; measured in straight line from mid-point of anterior clypeal margin to mid-point of posterior margin; the head must be carefully tilted to the position with the true maximum; excavations of posterior margin reduce HL;
HTL hind tibia length; maximum length of hind tibia;
HW head width; measured in full-face view directly above the eyes;
ML mesosoma length; measured as diagonal length from the anterior end of the neck shield to the posterior margin of the propodeal lobe;
PNW pronotum width; maximum width of pronotum in dorsal view;
SL maximum straight-line scape length excluding the articular condyle.
Indices:
HIHW/HL * 100;
SI1SL/HL * 100;
SI2SL/HW * 100;
MIHTL/ML * 100;
EI1EW/EL * 100;
EI2EW/HL * 100;
TIHW/HTL * 100.
Abbreviations:
q. gyne;
w. worker.
Pilosity inclination degree applies to this used in
Lasius alienus (Foerster, 1850), neotype (w.) (FOCOL0754): ‘‘GER: Eifel, 7.9.1991 / 37km SE Aachen / Schleiden / leg. Seifert // Formica aliena / Förtser 1850 / Neotype / des B.
L. austriacus Schlick-Steiner, Steiner, Schödl & Seifert, 2003, paratype (w.) (CASENT0916646): “#11055: Feldberg near / Pulkau, Austria (15°51’E/ / 48°40’N), 360 m / a.s.l., 06.08.2002. // leg. B.C. Schlick-Steiner & / F.M Steiner // Lasius austriacus / Schlick-Steiner / 2003 / PARATYPE” (
L. neglectus Van Loon, Boomsma & Andrasfalvy, 1990, paratype (w.) (CASENT0903220): ‘‘Lasius neglectus // HUNGARY / Budapest / 1.VII.88 / JJ. Boomsma // ANTWEB / CASENT / 0903220 //
Lasius paralienus Seifert, 1992, paratype (w.) (FOCOL0751): ‘‘Germania: Kr. Bautzen / 2 km S Weißenberg; N066 / 11.7.1991, leg. Seifert // Lasius paralienus / Seifert / Holotypus’’ (
Lasius psammophilus Seifert, 1992, holotype (w.) (FOCOL0752): ‘‘GER: Kr Weißwasser / 4 km N Steinbach: N 135 / 30.7.1991 leg. Seifert // Lasius psammophilus / Seifert / Holotype’’ (
Lasius turcicus Santschi, 1921, lectotype (w.) (CASENT0912297): ‘‘Lasius / turcicus / Santschi / Type / SANTSCHI det. 1920 // lectotype / desig. by / E. O. Wilson // Asie min. / Angora / G. d. Kerville // Sammlung / Dr. F. Santschi / Kairouan // ANTWEB / CASENT / 0912297’’ (
Holotype (w.): ‘‘Lasius / tapinomoides sp. nov. / HOLOTYPE // Collection L. Borowiec / Formicidae / LBC-GR00976 // GREECE, Crete, Rethymno Pr. / Antonios Spilia Gorge / 35°15.245 N,24°34.220 E / 11 V 2013, 342 m / L.Borowiec // CASENT0845075’’ (
2w. (pin): ‘‘Collection L. Borowiec / Formicidae / LBC-GR00467 // GREECE, W Crete, 339 m / Plemeniana n. Kandanos / 35.31666 N,23.71666 E / 2 V 2011, L. Borowiec (
The name refers to the similarity of this species to species of the Tapinoma genus, caused by a very shallow metanotal groove.
Worker.
Measurements: see Table
Head, mesosoma, petiole and gaster uniformly coloured, brown to dark brown. Antennae, tibiae and tarsi bright brown to orange (Figs
Measurements and indices | L. tapinomoides N = 10 | L. turcicus N = 10 |
---|---|---|
HL | 0.707 ± 0.02 (0.679–0.749) | 0.891 ± 0.06 (0.782–0.983) |
HW | 0.578 ± 0.03 (0.525–0.637) | 0.798 ± 0.06 (0.682–0.905) |
SL | 0.668 ± 0.02 (0.625–0.715) | 0.836 ± 0.04 (0.743–0.95) |
EL | 0.179 ± 0.008 (0.167–0.19) | 0.214 ± 0.012 (0.201–0.235) |
EW | 0.132 ± 0.004 (0.123–0.136) | 0.157 ± 0.015 (0.123–0.184) |
ML | 0.791 ± 0.04 (0.726–0.827) | 1.06 ± 0.08 (0.935–1.18) |
HTL | 0.709 ± 0.02 (0.682–0.76) | 0.892 ± 0.05 (0.799–0.961) |
PNW | 0.417 ± 0.018 (0.38–0.447) | 0.558 ± 0.04 (0.48–0.631) |
HI | 81.8 ± 3.3 (73.4–85.0) | 90.2 ± 1.8 (87.2–92.8) |
SI1 | 94.5 ± 1.5 (91.4–96.3) | 93.9 ± 2.9 (87.8–98.7) |
SI2 | 115.7 ± 4.4 (112.2–127.6) | 104.7 ± 3.6 (97.3–109.3) |
MI | 89.0 ± 3.1 (84.8–95.5) | 84.5 ± 3.0 (81.1–91.9) |
EI1 | 74.0 ± 3.6 (68.7–80.2) | 73.3 ± 4.6 (61.2–78.3) |
EI2 | 18.9 ± 0.9 (17.0–19.9) | 17.8 ± 1.3 (15.0–19.8) |
TI | 82.0 ± 2.6 (75.8–85.2) | 89.2 ± 2.2 (85.4–93.8) |
Head oval, 1.2 times as wide as long, lateral surfaces above eyes convex, occipital margin of head slightly convex (Figs
Genae with few adpressed to suberect setae (Figure
Mesosoma short, 1.9 times as long as wide. In lateral view, promesonotum low and flattened, metanotal groove very shallow, propodeum very low, propodeal dorsum slightly convex, propodeal declivity convex, less than twice length of propodeal dorsum (Figure
Petiole scale low, in lateral view with slightly convex sides, its dorsal crest thick and arched (Figure
Gyne.
Measurements and Indices (n=1): HL: 1.03; HW: 1.2; SL: 0.9; EL: 0.3; EW: 0.24; ML: 2.3; HTL: 1.3; PNW: 1.4; HI: 116.5; SI1: 87.4; SI2: 75; MI: 56.5; EI1: 80; EI2:23; TI: 92.
Head, mesosoma, petiole and gaster dark brown. Antennae, tibiae and tarsi bright brown to orange (Figs
Head trapezoidal, 1.1 times as wide as long, lateral surfaces above eyes convex, sides of occipital margin of head slightly convex, its central part concave (Figure
Mesosoma long, 1.6 times as long as wide. In lateral view moderately high, its dorsum slightly convex, propodeal dorsum slightly convex, propodeal declivity convex (Figure
Petiole scale low and wide, in lateral view with slightly convex sides, its dorsal crest wide and deeply concave in central part. Gaster with moderately thick and fine microreticulation, shiny, bearing pilosity denser than this covering mesosoma. Legs long, shiny, with fine microreticulation. Surface of tibia and femora with thin, dense, adpressed to subdecumbent setae, extensor profile of tibia with erect setae (Figs
Worker. As a member of the L. alienus group it is characterized by dorsal plane of scape, genae, and extensor profile of hind tibiae lacking or having very few erect or suberect setae and, in all species known from Crete, presence of >15 erect setae on the occipital edge of the head. Within the L. alienus group it can be classified to the L. turcicus complex. This complex can be characterized by small number of mandibular teeth (6–8), usually lack of suberect setae on hind tibia, very sparse clypeal pubescence, and more or less shallow metanotal groove. There are three known species of this complex: L. turcicus, L. neglectus and L. austriacus. Lasius tapinomoides sp. n. differs from all of them in presence of suberect to erect setae on antennal scape covering its apical part (ca. 1/3 upper part of the scape). Additionally from first two relatives it differs also in very shallow metanotal groove and from L. austriacus it differs in more flattened promesonotum, antennal sockets set not very close to posterior clypeal margin and habitat preferences. Lasius austriacus is related with xerothermous sites (
There are two other species of the L. alienus group known from Crete: L. bombycina Seifert & Galkowski, 2016 and L. turcicus Santschi, 1921. Lasius tapinomoides differs from all of them in very small body size. Nevertheless, at the first glance it can be confused with small workers of L. turcicus, from which it differs in the following measurements (L. tapinomoides sp. n. vs L. turcicus): HI: 81.8 ± 3.3 (73.4–85.0) vs 90.2 ± 1.8 (87.2–92.8), SI2: 115.7 ± 4.4 (112.2–127.6) vs 104.7 ± 3.6 (97.3–109.3), TI: 82.0 ± 2.6 (75.8–85.2) vs TI: 89.2 ± 2.2 (85.4–93.8). For more measurements data see Table
Gyne. During our fieldwork we could observe several gynes of L. tapinomoides and all detected nests were monogynous. Unfortunately, we were able to collect only a single specimen, therefore we provide very scarce data. As a coherent differential diagnosis is impeded, we decided to limit it to the most visible difference. Based on the morphology, L. tapinomoides differs from L. turcicus, L. austriacus and L. neglectus in presence of erect setae on tibiae.
Greece: Crete – endemic species.
Species inhabiting moist, closed canopy forests, which are most often located in stream valleys. Nesting in wet soil, under shallow and small rocks. Nests, most often, located in the vicinity of water sources. Workers were found in the litter or on the rocks surrounding the nest entrance. Colonies monogynous.
The following ant species were recorded in the same areas as L. tapinomoides:
Antonios Spilia Gorge: Aphaenogaster cecconii Emery, A. rugosoferruginea Forel, A. simonellii Emery, Camponotus candiotes Emery, C. lateralis (Olivier), Crematogaster ionia Forel, Messor wasmanni Krausse, Pheidole cf. pallidula, Stigmatomma denticulatum Roger, Temnothorax ariadnae Csősz, Heinze & Mikó, T. cf. graecus, T. cf. exilis, T. cf. luteus, Tetramorium caespitum (Linnaeus), T. diomedeum Emery;
Plemeniana n. Kandanos: Aphaenogaster rugosoferruginea, A. simonellii, Camponotus candiotes, C. gestroi Emery, C. lateralis, Colobopsis truncata (Spinola), Crematogaster cf. ionia, Lasius lasioides (Emery), Messor ibericus Santschi, Tetramorium caespitum;
Orthes Gorge: Aphaenogaster cecconii, A. cf. subterranea, A. simonellii, Camponotus baldaccii Emery, C. candiotes, C. jaliensis Dalla Torre, C. kiesenwetteri (Roger), C. rebeccae Forel, Crematogaster sordidula (Nylander), Lasius lasioides, Lepisiota nigra Dalla Torre, Messor cf. muticus, M. wasmanni, Tetramorium cf. caespitum, T. kephalosi Salata & Borowiec
n. Argioupolis: Aphaenogaster cecconii, A. rugosoferruginea, A. simonellii, Camponotus candiotes, C. lateralis, Crematogaster cf. ionia, Lepisiota nigra, Messor cf. muticus, M. wasmanni, Pheidole cf. pallidula, Plagiolepis pallescens sensu Radchenko, Temnothorax cf. luteus, T. ariadnae, T. cf. exilis, T. cf. graecus, Tetramorium cf. caespitum;
Preveli Beach: Aphaenogaster cecconii, Crematogaster ionia, Lasius psammophilus Seifert, Lepisiota melas (Emery), Pheidole cf. pallidula, Tapinoma festae Emery, Tetramorium kephalosi;
road to Preveli Beach loc. 1: Aphaenogaster rugosoferruginea, A. simonellii, Camponotus baldaccii, C. candiotes, C. gestroi, C. kiesenwetteri, C. lateralis, Cardiocondyla mauritanica Forel, Crematogaster cf. ionia, Cryptopone ochracea (Mayr), Lasius lasioides, L. bombycina Seifert & Galkowski, L. psammophilus, Lepisiota nigra, Messor ibericus, M. wasmanni, Pheidole cf. pallidula, Plagiolepis pallescens sensu Radchenko, Temnothorax cf. luteus, T. cf. graecus, T. recedens (Nylander), Tetramorium cf. caespitum;
Kato Malaki: Aphaenogaster simonellii, Camponotus baldaccii, C. gestroi, C. jaliensis, Crematogaster cf. ionia, Crematogaster sordidula, Messor ibericus, M. wasmanni, Pheidole cf. pallidula, Plagiolepis pallescens sensu Radchenko, Temnothorax ariadnae, T. recedens, Tetramorium diomedeum, Tetramorium punctatum Santschi;
Gorge of Richtis: Aphaenogaster rugosoferruginea, Camponotus candiotes, C. gestroi, C. lateralis, Crematogaster sordidula, Lasius lasioides, Messor wasmanni, Temnothorax cf. exilis, T. cf. graecus, Tetramorium cf. caespitum.
We examined several hundred specimens of Lasius turcicus from 76 samples across Greece and western Turkey (including initial nest samples), also numerous samples from Crete (see new material listed below). In none of these samples did we find specimens with such a shallow metanotal groove like in L. tapinomoides. This character is constant in all examined specimens and is always correlated with very small body size of workers and preference to humid habitats. Across all the sampled area within Greece and Turkey, where we collected species of the L. turcicus complex, we have not found workers or nests with workers similar to L. tapinomoides. Moreover, L. tapinomoides is the only known member of the L. turcicus complex that have suberect to erect setae on the apical 1/3 part of the antennal scape. This has prompted us to hypothesize that Cretan samples represent a new species.
Lasius bombycina Seifert & Galkowski, 2016
GREECE, Crete: 2w (EtOH), Omalos, 35.31667N,23.9E, 1122 m, 03.v.2014, leg. S. Salata (
Lasius myops Forel, 1894
GREECE, Crete: 3w. (pin), 3w. (EtOH), Anopoli, 35.26667N,24.06667E, 1780 m, 22.vii.2006, leg. Chatzaki M. (
Lasius illyricus Zimmermann, 1935
GREECE, Crete: 6w. (pin), Limnakarou platou, 35.13333N,25.46667E, 1130 m, 26.iv.2014, leg. S. Salata (
Lasius lasioides (Emery, 1869)
GREECE, Crete: 1w. (pin), Agia, 6 km SW Chania, 35.46666N,23.91666E, 22 m, 03.v.2011, leg. L. Borowiec (
Lasius psammophilus Seifert, 1992
GREECE, Crete: 4w. (EtOH), Agia Triada n. Kalamaki, 35.0508N,25.7542E, 1 m, 28.iv.2014, leg. S. Salata (
Lasius turcicus Santschi, 1921
GREECE, Crete: 3w. (EtOH), Kalives river, 35.45N,24.13333E, 26 m, 03.v.2014, leg. S. Salata (
1. | Maxillary palps short, not reaching midpoint between mouth and occipital foramen, body yellow to orange (Fig. |
L. myops Forel |
– | Maxillary palps long, distinctly reaching beyond midpoint between mouth and occipital foramen, body brown to black or bicoloured (Figs |
2 |
2. | Scape, genae and hind tibiae only with perfectly adpressed pubescence, without setae, occipital margin of head usually with 8 erect setae at most (Fig. |
L. lasioides (Emery) |
– | Scape, genae and hind tibiae often with occasional setae, pubescence not perfectly adpressed, occipital margin of head with more than 8 erect setae (Figs |
3 |
3. | Scape with few (>5) erect setae, body bicoloured, hind tibiae with numerous erect setae, mesosoma brighter than head and gaster (Figs |
L. illyricus Zimmerman |
– | Scape without or with maximum 5 erect setae, hind tibiae without or with a few erect setae, body uniformly coloured or head and mesosoma uniformly coloured, brighter than gaster (Figs |
4 |
4. | Clypeus with dense pubescence, average distance between setae 3.5 times shorter than their length (Fig. |
L. bombycina Seifert & Galkowski |
– | Clypeus with sparse pubescence, average distance between setae equal or longer than a half of their length (Figs |
5 |
5 | Workers small, ML 0.726–0.827 mm, mesosoma with very shallow metanotal groove, apical part of scape with >5 suberect to erect setae (Figs |
L. tapinomoides sp. n. |
– | Workers larger, ML 0.935–1.18 mm, metanotal groove distinct, apical part of scape without or with <5 suberect to erect setae (Figs |
6 |
6 | Metanotal groove relatively shallow, propodeal dorsum flattened, hind tibia usually without suberect setae, number of mandibular dents < 7.7 (Fig. |
L. turcicus Santschi |
– | Metanotal groove deeper and sharp, propodeal dorsum convex, hind tibia with few suberect setae, number of mandibular dents >7.7 (Fig. |
L. psammophilus Santschi |
Based on the literature (
Lech Borowiec would like to thank Jolanta Świętojańska (University of Wrocław) for her assistance during field trips. The authors wish also to thank the curator of