Aphaenogaster aktaci

Aphaenogaster aktaci was found in pitfall traps, set in a 50-70 years-old chestnut forest in Izmir-Bozdag, and in a 25-35 years-old oak forest.

In Turkey nests of Aphaenogaster aktaci were found most often under stones, occasionally under bark of dead tree trunks and in soil close to trees in old Pinus nigra, P. brutia and oak forests. In Greece nests were observed under large stones located close to streams, always in shaded areas of deciduous forests (Salata et al., 2021).

Identification
Salata and Borowiec (2018) - A member of the Aphaenogaster splendida group.

Kiran et al. (2008) - scapus distinctly surpassing occipital margin, funicular segments 2–6 that are 1.5 times longer than broad, and body sculpture dense and superficial (denser and more superficial than in obsidiana group). Aphaenogaster aktaci clearly differs from Aphaenogaster gibbosa, collected from Spain, especially by the large reticular sculptures on the head, stronger and deeper longitudinal rugae on the mesosoma and more distinct punctuation on the nodes. It also differs from Caucasian species by its large reticular sculptures without any punctuation and stronger and deeper longitudinal mesosomal rugae.

Salata et al. (2021) - Aphaenogaster aktaci is a very distinct species, the darkest and the most strongly sculptured species of the splendida species group. Its brown to dark brown coloration groups it with Aphaenogaster ovaticeps and dark specimens of Aphaenogaster rugosoferruginea. Aphaenogaster ovaticeps distinctly differs with regularly oval and less rugose head, and propodeal dorsum with transverse rugosities. Aphaenogaster rugosoferruginea differs in smaller size (WL 1.45–1.65 vs. 1.54–2.01), propodeal dorsum with transverse rugosities, smaller and thinner propodeal spines, and presence of pale spot on the base of the first gastral tergite. It is also paler than A. aktaci with body in most specimens yellowish-brown; only the darkest specimens have mesosoma as brown colored as in pale specimens of A. aktaci. Also, these three dark colored species are well separated geographically: A. ovaticeps is distributed in the Ionian Islands, western part of Balkans and northern regions of Italy, A. rugosoferruginea is endemic to Crete, and A. aktaci is distributed in the northern Aegean Islands (Lesbos) and western Turkey (Isparta and Izmir provinces).

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

Nomenclature

 * . Aphaenogaster (Attomyrma) aktaci Kiran & Tezcan, in Kiran, et al. 2008: 690, fig. 1 (w.) TURKEY.
 * Salata & Borowiec, 2018c: 5 (q.).
 * Status as species: Kiran & Karaman, 2012: 16; Borowiec, L. 2014: 9; Salata & Borowiec, 2018c: 3.

Taxonomic Notes
Kiran et al. (2008) placed this species in the Aphaenogaster gibbosa group sensu Schulz (1994), but Salata & Borowiec (2018b) suggest it belongs to the A. splendida group due to slimmer body, longer legs and antennae, more oval head and stronger sculpture of head than in any member of the gibbosa group (Salata & Borowiec 2018a).

Worker
Head longer than broad, broadest below eyes, occipital margins oval, without edge, occiput slightly concave. The sculpture of the head dorsum distinct, irregular and rough but not as rough as obsidiana group, from the middle of the head to occiput with various sized reticulate, increasing in size near to the occiput. Internal surfaces of reticulation without punctuations. Frontal area raised and carinate. Clypeus with a few weakly developed striae, anterior border of clypeus rather broad and shallowly notched in the middle. Mandibles well developed, triangular shaped, with few longitudinal striae and with 4 distinct teeth. Scapus surpassing occipital margin distinctly and not thickening towards the funiculus as obsidiana group. 2–6 funicular segments 1.5 times longer than broad without antennal club. Mesosoma not as robust as in obsidiana group being a little more prolonged, having regular distinct rugae appearing matt; mesonotum distinctly raised behind the pronotum. Metanotal groove distinct. Propodeal spines well developed and sharp. Propodeal dorsum smooth. Dorsum of nodes with 2–3 longitudinal striae and weakly punctuate. Gaster smooth and shiny; base of first gastral tergite longitudinally sculptured (as in the gibbosa group). Body with light brown, rather sparse, thick, erect hairs. Colour, reddish brown, head and gaster darker, legs lighter. All the body matt, except gaster.

Queen
Salata and Borowiec (2018) - Gyne (n=3): HL: 1.55 ± 0.01 (1.54-1.57); HW: 1.35 ± 0.03 (1.31-1. 37); SL: 1.32 ± 0.008 (1.31-1.33); EL: 0.39 ± 0.03 (0.36-0.43); EW: 0.3 ± 0.03 (0.27-0.36); ML: 2.6 ± 0.09 (2.56-2.72); PSL: 0.6 ± 0.02 (0.59-0.62); SDL: 0. 3 ± 0.004 (0.3-0.31); PEL: 0.8 ± 0.05 (0.79-0.89); PPL: 0.51 ± 0.01 (0.49-0.52); PH: 0.53 ± 0.01 (0.52-0.54); PPH: 0.64 ± 0.02 (0.62-0.66); PNW: 1.49 ± 0.2 (1.34-1.74); PEW: 0.52 ± 0. 1 (0.44-0.65); PPW: 0.65 ± 0.06 (0.61-0.72); HI: 87.0 ± 1.7 (85.1-88.3); SI1: 85.3 ± 0.9 (84.4-86.2); SI2: 98.1 ± 2.8 (96.5-101.3); MI: 56.5 ± 6.4 (52.6-63.9); EI1: 79.3 ± 4.9 (75.0-84.6); EI2: 19.9 ± 2.7 (17.5-22.9); PI: 129.1 ± 9.2 (120.0-138.5); PPI: 97.0 ± 5.2 (90.9-100.0).

Colour. Whole body brown. Frons and gaster slightly darker. Head. Oval, lateral surfaces below eyes straight, gently rounded on the posterior edges, occipital margin of head convex. Anterior margin of the clypeus gradually convex. Eyes big, oval, 0.25 times as long as length of the head. Antennal scape short, slightly curved, 0.8 times as long as length of the head, not exceeding beyond occipital margin of head, in apex gradually widened, its base with small teeth. Pedicel more than 2 times longer than wide; average 1.2 times longer than second segment of funiculus. Other funicular segments more than 1 ½ times longer than wide. Surface of scape with very fine, short and sparse striae and sparse punctation; covered with thin, moderate dense, adpressed to decumbent setae, shorter than ½ of scape width. Mandibles triangular, with thick, longitudinal striae, shiny. Clypeus shiny with sparse, thick, longitudinal striae, area between striae with gentle microreticulation or smooth, shiny. Frontal carinae short, slightly extending across the fronts of the antennal fossae. Antennal fossa deep, with sparse roundly curved striae, area between striation smooth. Frontal lobes narrow, smooth with thick longitudinal striae. Head on the whole surface with thick, moderately dense, longitudinal reticulation, area between rugae with irregular, fine and thick rugae, shiny. Entire head bearing thick, suberect to erect, pale setae. Mesosoma. Short, square, 1.7 times as long as head; in lateral view scutum slightly convex, scutellum located above scutum, and globular; propodeal spines triangular, long, with wide base, inclined at the 45° angle; dorsal surface of propodeum inclined towards its posterior surface. Pronotum with longitudinal, horizontal, weak but dense striation, area between striae smooth or with microreticulation, shiny. Scutum with extremely fine and sparse microreticulation and shiny, only on its posterior edge with some short, longitudinal wrinkles; scutellum and axilla with longitudinal striation; scutum centre smooth or with extremely sparse and fine microreticulation; area between striae smooth and shiny; propodeum shiny, with dense transverse to irregular striation. Anepisternum and katepisternum shiny with sparse and fine microreticulation; lateral edges with very dense, thick longitudinal striation. Mesosoma dorsum with sparse, thick, erect setae. Petiole. Peduncle moderate, node with anterior and posterior faces convex, its dorsal surface wide and convex. On the whole surface covered by dense microreticulation and sparser thick, irregular striae and long, thick erect setae. Postpetiole. In lateral view, regularly rounded, 0.8 times as long as wide, apical half with gently rounded sides. On the whole surface covered by dense microreticulation and sparser thick, irregular striae and long, thick erect setae. Gaster. Smooth and shiny, bearing dense, long, suberect to erect, pale setae.

Type Material
Holotype – worker: Turkey, Izmir-Bozdag-Golcuk Village 2 km E, (38°19' N, 28°06' E), 1160 m a.s.l., 09.VI.2001, 01/1295a (leg. S. Tezcan) (TU).

Paratypes: 49 workers, from same locality as the holotype, 28.IV.2001: 01/1222a, 1225a; 26.V.2001: 01/1270b, 1272c, 1274a; 09.VI.2001: 01/1291c, 1293a, 1294, 1295a; 01.VII.2001: 01/1310c, 1311b, 1318a; 10.VII.2001: 01/1332d; 22.VII.2001: 01/1352d; 03.VIII.2001: 01/1370b, 1374a, 17.VIII.2001: 01/1394b, 1395b, 1397b, 1398; 30.VIII.2001: 01/1417b, 1419a; 29.IX.2001: 01/1466; 13.X.2001: 01/1489 (leg. S. Tezcan) (TU, LEMT); 7 workers, Turkey, Izmir SE of Bozdag and 2 km of Golcuk Lake, (38°18' N, 28°02' E), 1030 m a.s.l., 14.IV.2001: 01/1207; 03.VIII.2001: 01/1375f; 17.VIII.2001: 01/1400a (leg. S. Tezcan) (TU).

Etymology
This species is dedicated to Prof. N. Aktac who thoroughly managed this study from the beginning.

References based on Global Ant Biodiversity Informatics

 * Borowiec L. 2014. Catalogue of ants of Europe, the Mediterranean Basin and adjacent regions (Hymenoptera: Formicidae). Genus (Wroclaw) 25(1-2): 1-340.
 * Kiran K., N. Aktaç, and S. Tezcan. 2008. Three new species of ants, genus Aphaenogaster (Hymenoptera: Formicidae) from Turkey. Biologia 63 (5): 689-695.
 * 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.