Perissomyrmex nepalensis Radchenko

Ogata, K. & Okido, H., 2007, Revision of the ant genus Perissomyrmex with notes on the phylogeny of the tribe Myrmecinini., Advances in ant systematics (Hymenoptera: Formicidae): Homage to E. O. Wilson - 50 years of contributions. (Memoirs of the American Entomological Institute 80), pp. 352-369 : 361-362

Perissomyrmex nepalensis Radchenko

(Figs. 16 f, 17 c)

Perissomyrmex nepalensis Radchenko 2003: 12. Holotype worker. Nepal.

Diagnosis

Worker, measurements (mm): TL 3.74 - 4.38, HL 0.90 - 1.10, HW 0.92 - 1.10, SL 0.8 - 0.9, PW 0.56 - 0.64, ML 1.00 - 1.10, GL 1.02 - 1.30, GW 0.80 - 0.96. Indices: CI 100 - 102, SI 82 - 87.

Four teeth on anterior margin of clypeus well isolated; median paired teeth large and distinct, lateral paired teeth small and spaced from the median teeth; median notch converted V shape; the bottom of notch not reaching anterior margin of lateral ridge in front of antennal insertion. Promesonotum raised but less convex. Propodeal spine directed backward and curved upward. Ventral margin of petiole nearly straight. Subpetiolar process absent. Costulation on head and pronotum low and spaced, unsculptured area on mesosoma and propodeum wider. Body color light reddish brown, antennae and legs yellowish.

Specimens examined: 2 workers, W. Bengal, Darjeering, Tiger Hill , 2450 m, 28. viii. 1997, India ( BMNH).

Remarks

The dorsal outline of the promesonotal area varies in the size of workers. In minor worker the area is less raised but in major worker weakly convex in profile. P. nepalensis is distinguishable from P. monticola by the ventral profile of the petiole: nearly straight in the former, but widely convex in the latter. Sculpturation of P. nepalensis is weaker and more spaced than that of P. montiocola . Radchenko (2003) noticed the standing hairs on the antennae and legs in distinguishing P. nepalensis from P. monticola ; short and abundant in the former, long and sparse in the latter.

The species was found in Himalayan region (Nepal and northeastern India) at the altitudinal range of 2450 to 3000 m, collected by pitfall traps (Radochenko, 2003).