Tetramorium kephalosi

Specimens were collected in dry and sunny habitats from the sea coast up to 1090 m. Nests were found at roadsides, in pastures, along lake shores and in scrub. In one nest 7 gynes were collected. (Salata and Borowiec 2017)

This recently described species has been confused with Tetramorium semilaeve. In Greece appears to be a very common species, known from all Greek provinces (Borowiec et al., 2022).

Identification
Salata and Borowiec (2017) - Tetramorium kephalosi in all castes is extremely similar to Tetramorium semilaeve. The best distinguishing characters are structures of the male. However, in examining a group of workers from a nest series the following differences can be observed (characters for T. semilaeve in parentheses): workers of T. kephalosi differ in the occipital margin of the head more or less concave (usually straight), ground surface of head usually shiny (with more or less visible microreticulation) and head stouter, slightly wider than long (slimmer, slightly longer than wide); in nests of T. kephalosi predominate yellowish brown to brown coloured specimens (yellow).

Gynes of T. kephalosi differ in their darker brown body (light brown) and thinner head rugae and finer and sparser punctuation between rugae (thicker head rugae and coarser and denser punctuation between rugae). Males of T. kephalosi differ in their larger size with ML 1.831-2.022 (1.626-1.785) and a distinctly narrower, slightly trapezoidal head (broad, rounded on sides), the scutum between sutures partly striate (usually completely smooth or with few indistinct striae), behind sutures with broad striate area (not striate or with narrow striate area), scutellum anteriorly with distinct transverse striae (smooth or with indistinct striae), anepisternum in posterior half distinctly striate (smooth or narrowly striate along upper margin); the male genitalia of T. kephalosi in profile is slightly less constricted before the apex (slightly more constricted) with the inner margin of the paramere before the apical denticle with very narrow lamella parallel to the inner margin (with dentiform plate distinctly extending beyond the inner margin).

Workers of Tetramorium galaticum and Tetramorium bellerophoni differ in paler coloration, yellow body (in T. kephalosi usually yellowish-brown); workers of T. bellerophoni usually have more distinctly striated head than workers of T. kephalosi. Workers of Tetramorium hippocratis distinctly differ in their dark brown to black body.

Gynes of T. galaticum and T. bellerophoni differ in their paler body colouration, yellow to reddish-yellow (usually brown in T. kephalosi) and larger size with ML always above 2.0 and MW above 1.3 (in T. kephalosi below 1.96 and 1.22 respectively). The scutum in gynes of T. kephalosi is usually more distinctly striated than in both relatives. Males of T. galaticum and T. bellerophoni differ in the top of the inner margin of the paramere before the apical denticle is straight, without a narrow lamella (with lamella in T. kephalosi), male of T. bellerophoni also differs in they clypeus with circular striation (parallel in T. kephalosi).

Gynes of T. hippocratis differ in their dark brown to black body (brown in T. kephalosi) and stouter mesosoma with ML/MW ratio approximately 1.59 (in T. kephalosi 1.70). The scutum in T. hippocratis is always more striated than in gynes of T. kephalosi. Males of T. hippocratis differs in their almost black body (dark brown in T. kephalosi) and smaller size with ML 1.698-1.827 vs. 1.831-2.022 and have more converging posterad frontal lobes (FL/FR 1.152-1.267 vs. 1.0-1.146). The structure of the male genitalia of T. hippocratis is very similar to T. kephalosi. Both species have a sharp lamella on the inner margin of the apex of the paramera but in T. hippocratis the genitalia in lateral view is more distinctly constricted before the apex than in T. kephalosi with a more angulate inner angle.

Distribution
Salata and Borowiec (2017) - Dalmatia, Cyclades, Epirus, Ionian Islands, Peloponnese, Sterea Ellas, Thessaly, Thrace and Crete. The eastern border of its range is unclear due to a lack of nest samples with males. Some examined workers and gynes from Thessaly and the southern part of Greek Macedonia appear to belong to T. kephalosi but some populations from northern Greek Macedonia, Thrace and Bulgaria look slightly different due to generally paler ground colour and often more reduced head rugosities. Also some populations from Dodecanese appear to be different taxa due to less sculptured head and mesosoma.

Distribution based on Regional Taxon Lists
Palaearctic Region: Croatia, Greece.

Nomenclature

 *  kephalosi. Tetramorium kephalosi Salata & Borowiec, 2017: 290, figs. 28-44 (w.q.m.) GREECE.

Worker
(n=42): CL: 0.742 ± 0.047 (0.615-0.827); POC: 0.289 ± 0.028 (0.235-.346); CW: 0.732 ± 0.054 (0.592-0.827); FR: 0.253± 0.019 (0.212-0.29); FL: 0.257 ± 0.019 (0.212-0.291); SL: 0.534 ± 0.031 (0.444-0.603); OMD: 0.181 ± 0.015 (0.156-0.212); EL: 0.14 ± 0.012 (0.112-0.167); EH: 0.102 ± 0.007 (0.089-0.115); ML: 0.801 ± 0.069 (0.648-0.939); SPSP: 0.141 ± 0.013 (0.111-0.168); SPL: 0.102 ± 0.013 (0.078-0.123); PEL: 0.203 ± 0.02 (0.156-0.257); NOL: 0.168 ± 0.017 (0.134-0.207); PPL: 0.182 ± 0.017 (0.14-0.223); PEH: 0.243 ± 0.022 (0.193-0.285); NOH: 0.17 ± 0.016 (0.134-0.201); PPH: 0.238 ± 0.023 (0.201-0.291); MW: 0.459 ± 0.035 (0.38-0.528); PEW: 0.23 ± 0.024 (0.178-0.293); PPW: 0.261 ± 0.023 (0.215-0.324); CS: 0.738 ± 0.05 (0.604-0.827); EYE: 0.163 ± 0.007 (0.145-0.175); CL/CW: 1.017 ± 0.022 (0.963-1.059); FR/CS: 0.344 ± 0.012 (0.317-0.37); FL/FR: 1.016 ± 0.02 (0.979-1.054); SL/CS: 0.725 ± 0.017 (0.699-0.769); MW/CS: 0.624 ± 0.011 (0.594-0.646); PEW/PPW: 0.881 ± 0.037 (0.797-0.937); NOH/NOL: 1.026 ± 0.069 (0.884-1.204); NOH/PEL: 0.846 ± 0.074 (0.696-1.123); NOL/PEL: 0.827 ± 0.05 (0.726-0.942); PEH/NOL: 1.462 ± 0.076 (1.321-1.623); PEW/PEH: 0.945 ± 0.045 (0.84-1.051); CS/PEW: 3.203 ± 0.152 (2.788-3.592); CS/PPW: 2.816 ± 0.108 (2.521-2.994); CW/MW: 1.604 ± 0.029 (1.547-1.683).

Small to medium size, CS 738 [604, 827]. In most specimens whole body yellowish-brown, the darkest specimens brown to dark brown but never black, the palest specimens yellow, appendages yellow. Head slightly as long as wide to slightly longer than wide CL/CW 1.017 [0.963, 1.059], with almost parallel sides, straight to slightly concave occipital margin and rounded occipital corners. Eyes small, EYE 0.163 [0.145, 0.175]. Frons moderately wide, FR/CS 0.344 [0.317, 0.37], frontal lobes as wide as frons, FL/FR 1.016 [0.979, 1.054]. Scape short, SL/CS 0.725 [0.699, 0.769], without dorsal carina basally, surface smooth and shiny. Promesonotal dorsum slightly convex, metanotal groove shallow but perceptible. Propodeal teeth short, triangular, apex of spine located approximately at 2/3 height of mesosoma. Dorsal surface of petiole flat to slightly convex, NOH/NOL 1.026 [0.884, 1.204], petiole moderately high, PEH/NOL 1.462 [1.321, 1.623], postpetiole distinctly transverse. General appearance finely rugose, ground surface shiny. Head dorsum partly longitudinally rugose and shiny between rugae, rugae extend occipital margin of head, occiput laterally mostly smooth and shiny, sides in anterior half longitudinally rugose and shiny between rugae. In most specimens between frontal rugose area and rugosities along ocular area on each side runs longitudinal stripe without rugosities but smooth area never exceeds 1/5 of the anterior surface of head; in extremely sculptured specimens almost whole frontal surface of head with long rugae with very small smooth patch, in extremely fine sculptured specimens only frons with rugae, ocular area, top of head and postocular area smooth and shiny, the level of development of sculpture is correlated with size and coloration of workers, small and paler coloured specimens usually have less developed sculpture than large and darker coloured specimens. Alitrunk dorsum longitudinally rugose and microreticulate but never reticulate, also specimens with reduced head sculpture have complete rugae along pronotum. Sides of pronotum and meso- and metapleuron usually coarsely microreticulate, sometimes reticulation tends to form transverse lines but surface never appears striate or rugose, pronotum close to ventral margin with small, convex, shiny patch. Dorsum of petiolar node smooth and shiny with sides carinate, lateral surface microreticulate. Dorsum of postpetiole smooth and shiny, sides microreticulate. First gastral tergite smooth and shiny. Whole dorsum, including head, covered with sparse setae, the longest on pronotum and the shortest on frons. Ventral surface of head with sparse short and 2-5 moderately long setae not forming a psammophore.

Queen
(n=21): CL: 1.037 ± 0.027 (0.994-1.084); POC: 0.4 ± 0.021 (0.363-0.446); CW: 1.137 ± 0.034 (1.078-1.181); FR: 0.393 ± 0.011 (0.366-0.413); FL: 0.39 ± 0.011 (0.369-0.411); SL: 0.729 ± 0.016 (0.704-0.765); OMD: 0.227 ± 0.01 (0.212-0.246); EL: 0.288 ± 0.01 (0.268-0.302); EH: 0.218 ± 0.007 (0.212-0.235); ML: 1.887 ± 0.04 (1.789-1.951); SPSP: 0.297 ± 0.017 (0.257-0.324); SPL: 0.208 ± 0.019 (0.19-0.279); PEL: 0.33 ± 0.011 (0.313-0.355); NOL: 0.251 ± 0.01 (0.234-0.268); PPL: 0.324 ± 0.014 (0.291-0.352); PEH: 0.448 ± 0.014 (0.425-0.469); NOH: 0.29 ± 0.023 (0.245-0.324); PPH: 0.468 ± 0.024 (0.422-0.514); MW: 1.107 ± 0.054 (1.027-1.213); PEW: 0.4 ± 0.022 (0.346-0.441); PPW: 0.528 ± 0.037 (0.469-0.587); CS: 1.087 ± 0.028 (1.036-1.129); EYE: 0.231 ± 0.007 (0.219-0.243); CL/CW: 0.912 ± 0.017 (0.883-0.941); FR/CS: 0.362 ± 0.013 (0.342-0.388); FL/FR: 1.018 ± 0.01 (1.0-1.056); SL/CS: 0.67 ± 0.014 (0.646-0.688); MW/CS: 1.022 ± 0.034 (0.983-1.103); PEW/PPW: 0.76 ± 0.042 (0.685-0.857); NOH/NOL: 1.158 ± 0.09 (1.0-1.317); NOH/PEL: 0.881 ± 0.073 (0.756-1.035); NOL/PEL: 0.761 ± 0.03 (0.685-0.8); PEH/NOL: 1.789 ± 0.09 (1.645-1.974); PEW/PEH: 0.894 ± 0.043 (0.774-0.972); CS/PEW: 2.718 ± 0.162 (2.553-3.202); CS/PPW: 2.06 ± 0.119 (1.874-2.308); CW/MW: 0.98 ± 0.03 (0.907-1.018); WAIST: 0.856 ± 0.04 (0.745-0.909).

Moderate size, CS 999 [948, 1025]. Whole body brown, gaster slightly paler than head and mesosoma. Head wider than long, CL/CW 0.912 [0.883-0.941], with straight subparallel sides, straight or shallowly emarginate occipital margin and rounded occipital corners. Frons moderately wide, FR/CS 0.362 [0.342-0.388], frontal lobes approximately as wide as frons, FL/FR 1.018 [1.0-1.056]. Scape short, SL/CS 0.67 [0.646-0.688], without dorsal carina basally, smooth and shiny. Head as wide as scutum, MW/CS 1.022 [0.983-1.103]. Propodeal teeth short, triangular. Dorsal crest of petiolar node in frontal view slightly convex. Petiolar node dorsum steeply rounded backward. Petiole and postpetiole relatively narrow, but postpetiole distinctly transverse approximately 1.4 times as wide as long, WAIST 0.896 [0.745-0.909]. General appearance smooth and shiny. Head dorsum, occiput and sides rugulose, ground surface indistinctly microreticulate but shiny. Frons in strongly sculptured morphotype longitudinally rugulose, in finely sculptured morphotypes with oval, smooth patches close to eyes. Mesosoma flat, sides of pronotum visible from above. Scutum and scutellum punctate along sides, in less sculptured specimens smooth and shiny with diffused microreticulation and scutum at base with very short striation, in more sculptured specimens scutellum in corners with very short rugae and scutum in basal part with thin longitudinal striae never extending to half length of scutum. Sides of pronotum microreticulate with fine longitudinal striation only at base with small, smooth and shiny area, anepisternum from completely smooth and shiny to finely striate in posterior half, katepisternum from completely to mostly smooth and shiny, at most in 1/4 posterior part microreticulate and obliquely striate. Almost whole surface of petiolar node distinctly reticulate only top with small smooth and shiny area. Postpetiole with rounded sides, on sides granulate, at top microreticulate with small smooth and shiny area. First gastral tergite smooth and shiny. Whole dorsum, including head, covered with short, sparse setae. Ventral surface of head with few short and 3-5 longer setae, the longest as long as to 1.5 times longer than frontal setae, arising posteriorly to buccal cavity.

Male
(n=12): CL: 0.699 ± 0.018 (0.664-0.726); POC: 0.302 ± 0.019 (0.262-0.332); CW: 0.811 ± 0.023 (0.765-0.863); FR: 0.246 ± 0.01 (0.235-0.268); FL: 0.261 ± 0.015 (0.235-0.291); SL: 0.347 ± 0.016 (0.33-0.38); OMD: 0.063 ± 0.012 (0.045-0.089); EL: 0.314 ± 0.007 (0.302-0.324); EH: 0.253 ± 0.008 (0.24-0.265); ML: 1.909 ± 0.055 (1.831-2.022); SPSP: 0.26 ± 0.012 (0.246-0.279); SPL: 0.244 ± 0.018 (0.201-0.268); PEL: 0.344 ± 0.012 (0.324-0.368); NOL: 0.247 ± 0.025 (0.179-0.279); PPL: 0.301 ± 0.022 (0.246-0.335); PEH: 0.325 ± 0.017 (0.291-0.352); NOH: 0.188 ± 0.015 (0.168-0.212); PPH: 0.478 ± 0.034 (0.38-0.525); MW: 1.137 ± 0.045 (1.065-1.213); PEW: 0.377 ± 0.014 (0.345-0.391); PPW: 0.533 ± 0.042 (0.447-0.615); CS: 0.755 ± 0.019 (0.721-0.795); EYE: 0.361 ± 0.05 (0.202-0.398); CL/CW: 0.862 ± 0.017 (0.831-0.887); FR/CS: 0.326 ± 0.016 (0.309-0.363); FL/FR: 1.061 ± 0.04 (1.0-1.146); SL/CS: 0.459 ± 0.013 (0.439-0.478); MW/CS: 1.506 ± 0.059 (1.425-1.609); PEW/PPW: 0.702 ± 0.035 (0.636-0.738); NOH/NOL: 0.773 ± 0.12 (0.627-1.123); NOH/PEL: 0.549 ± 0.059 (0.456-0.633); NOL/PEL: 0.717 ± 0.07 (0.542-0.806); PEH/NOL: 1.342 ± 0.19 (1.086-1.776); PEW/PEH: 1.162 ± 0.079 (1.085-1.326); CS/PEW: 2.013 ± 0.077 (1.91-2.138); CS/PPW: 1.411 ± 0.082 (1.236-1.5); CW/MW: 0.665 ± 0.03 (0.621-0.702).

Head and mesosoma dark brown to almost black, gaster brown, appendages yellowish. Head slightly trapezoidal, with almost straight occipital margin and more or less rounded occipital corners. Scutum distinctly wider than head. Propodeum from regularly rounded to finely angulate in profile. Dorsal crest of petiolar node with obtuse transversal edge, slightly emarginated in frontal view. Head distinctly sculptured, with radial rugosities around ocelli, circular rugosities around antennal scapi and oblique rugosities on frons, dull. Scutum in anterior part mostly with distinct striation only in anterior part smooth and shiny, behind Mayrian furrows with more or less developed longitudinal striation, sides broadly smooth and shiny. Scutellum from mostly smooth and shiny to mostly with transverse, circular and oblique striation. Sides of pronotum microreticulate and distinctly striate. Anepisternum from completely smooth and shiny to striate along upper margin, in extreme case posterior third striate, katepisternum mostly smooth and shiny only along upper margin and in posterior corner microreticulate, propodeum microreticulate with longitudinal rugosities, dull. Dorsum of petiolar node microgranulate and microreticulate, dull, postpetiole mostly microreticulate only top partly smooth and shiny. First gastral tergite smooth and shiny. Male genitalia stout, in lateral view indistinctly constricted before apex with obtuse inner angle, top moderately long and dense pubescent, dorsal margins of parameres almost straight, ventral margins deeply incised before apical hook, top of inner margin of paramere before apical denticle almost straight, without dentiform plate extending beyond the sharp edge of paramere but with narrow lamella.

Type Material
Type material: holotype worker: Greece, Ionian Is., Kefalonia, Mt. Kalon Oros, 658 m, 38,34205 N / 20,56472 E, 26 VI 2014, L. Borowiec, Collection L. Borowiec, Formicidae, LBC-GR01511 ( no. 1225); paratype gyne: the same data (MNHW no. 1225a); 8 paratype males, 4 paratype gynes, 17 paratype workers: the same data (,, , TU).

Etymology
Named after Kephalos (Greek: ΚXϕαλος), a hero of Greek mythology which gave the name of the island Kephalonia, the type locality for this new species.

References based on Global Ant Biodiversity Informatics

 * Borowiec L., and S. Salata. 2017. Ants of the Peloponnese, Greece (Hymenoptera: Formicidae). Polish Journal of Entomology 86: 193-236.
 * Salata S., L. Borowiec, and A.Trichas. 2018. Taxonomic Revision of the Cretan Fauna of the Genus Temnothorax Mayr, 1861 (Hymenoptera: Formicidae), with Notes on the Endemism of Ant Fauna of Crete. Annales Zoologici (Warsaw) 68(4): 769-808.
 * Salata S., and L Borowiec. 2017. Species of Tetramorium semilaeve complex from Balkans and western Turkey, with description of two new species of (Hymenoptera: Formicidae: Myrmicinae). Annales Zoologici (Warsaw) 62:279–313.
 * Salata S., and L. Borowiec. 2018. A new species of the ant genus Lasius Fabricius, 1804 from Crete (Hymenoptera, Formicidae). ZooKeys 789: 139–159.
 * Salata S., and L. Borowiec. 2018. Taxonomic and faunistic notes on Greek ants (Hymenoptera: Formicidae). Annals of the Upper Silesian Museum in Bytom Entomology 27: 1-51.
 * Salata S., and L. Borowiec. 2019. Preliminary division of not socially parasitic Greek Temnothorax Mayr, 1861 (Hymenoptera, Formicidae) with a description of three new species. ZooKeys 877: 81-131.