Lasius tunisius, Seifert, 2020

Seifert, Bernhard, 2020, A taxonomic revision of the Palaearctic members of the subgenus Lasius s. str. (Hymenoptera, Formicidae), Soil Organisms 92 (1), pp. 15-86 : 73

4.4.43 Lasius tunisius sp. nov.

Etymology. The name refers to Tunisia where the species has been found.

Type material. Holotype and 5 paratype workers on two pins labelled ”TUNESIEN-08, 10-15 km S. Ain Draham, Kroumirie, 600-800 mH, 02.10.1995 Leg. Schulz & Vock 932“; depository SMN Görlitz.

All material examined. Only the type series was available.

Geographic range. Only known from the type locality which is situated at about 36.712°N, 8.671°E, 700 m in a rather humid area fully covered by broad-leafed woodland.

Biology. Unknown. Apparently a woodland species.

Diagnosis ( Tab. 8 , Figs. 83 –84; key):

Absolute size large (CS 994µm). Head length and scape length indices slightly smaller than in related species (CL/CW 900 1.076, SL/CS 900 1.018). Outlines of head in dorsal view more rounded than in emarginatus ; postocular distance significantly larger (PoOc/CL 900 0.238), eye large (EYE/CS 900 0.247) and torulo-clypeal distance rather low (dClAn 900 4.41). In contrast to poorly developed pilosity on other body parts, frontal clypeal margin with a conspicuous row of setae, only moderately decreasing their length laterad: the 3rd paramedian setae as long as 68–83% of the innermost (1st paramedian) setae; in other species this ratio is 43–65 %. Median clypeal margin slightly truncate. Terminal segment of maxillary palp long (MP6/CS 900 0.230). Pubescence on clypeus dilute (sqPDCL 900 5.01); frontal pubescence extremely appressed and short (PLF 900 19.0). Least hairy species of the L. emarginatus species complex; setae on dorsum of scape and flexor profile of hind tibia completely absent, pronotal hairs shorter than gular hairs (nOcc 900 6.4, nGen 900 3.1, nGu 900 4.0, nSc 900 0, nHT 900 0, nSt 900 4.1, PnHL/CS 900 0.112, GuHL/CS 900 0.123). Lateral profile of propodeum similar to brunneus : its slope very straight, meeting the dorsal profile at distinct angle of 95– 100°. Petiole scale: rather high, subquadrate; dorsal crest wide, emarginate. Coloration: blackish head and gaster, mesosoma dark reddish brown, femora blackish brown, tibiae slightly lighter. Scape yellowish.

Comments. The character combination of Lasius tunisius sp. nov. appears unmistakable already under subjective inspection. When run in a PCA, the 6 available specimens cluster clearly separate from any African species.

Figures

Figs. 83 and 84: Lasius tunisius sp. nov.; holotype