Lasius lawarai Seifert 1992

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 : 74

4.4.45 Lasius lawarai Seifert 1992

Lasius lawarai Seifert 1992 [type investigation]

Type material: Holotype and 5 paratype workers labelled ” PAKISTAN. Dir , Lawarai-Pass 21e, 2700 m; 21. v. 1983 Besuchet-Löbl“; depositories: MHN Genève, 2 paratypes in SMN Görlitz.

Lasius breviscapus Seifert 1992 syn. nov.

Lasius breviscapus Seifert 1992 [type investigation]

Type material: Holotype and 4 paratype workers labelled ” Chopal , 2400-2750m, 7.5.1977 “ and ” Indien Him. Prad. Wittmer, Brancucci “; depository NHM Basel.

All material examined. A total of 10 nest samples with 29 workers were subject to NUMOBAT investigation. These originated from India (3 samples) and Pakistan (7 samples). For details see supplementary information SI1.

Geographic range. Known so far only from the SW flank of the Himalayas at elevations between 2300 and 3100 m, along a line delimited by 35.8°N, 71.8°E and 30.8°N, 77.8°E.

Diagnosis ( Tab. 9 , Figs. 87 –88; key; images in www. antWeb.org with specimen identifiers CASENT0911182, CASENT0912289):

Within the Himalayan-Tibetan species of the subgenus, the species is well separable as a combination of small eyes (EYE/CS 900 0.214), large postocular index (PoOc/ CL 900 0.261) and short scape (SL/CS 900 0.948). Seta counts (those of nSc and nHT in particular) are weakly reproducible because of unclear thickness differences between elongated pubescence hairs and setae. A frequent coloration is head, mesosoma petiole and gaster dark brown; mandibles, antennae, tibiae and tarsae light yellowish brown.

Biology. Unknown.

Comments. The synonymization of Lasius breviscapus is explained as follows. Based on a single sample of 5 workers, Seifert (1992) described L. breviscapus as a species because of very small body size and an extremely low RAV-corrected scape length. The sample means of CS and SL/CS 900 are 731 µm and 0.907 whereas these means vary in the nine samples of L. lawarai 789–870 µm and 0.936 –0.981 – i.e., the data are clearly outside the normal distribution of L. lawarai known in that time. However, I was unaware in 1992 that nanitic, malnutritioned workers of Lasius , typically those reared first by a founding queen, may show a reduction of relative scape length in contradiction to the overall allometric rule that SL/ CS increases with reduction of body size. Furthermore, considering all 16 standard characters, no exploratory data analysis could expose the L. breviscapus type series outside the L. lawarai cluster and both taxa share the rare characters of small eye size and large postocular index.

Figures

Figs. 87 and 88: Lasius lawarai; paratype