Ogata, K., 2007:
Figures 16 d, e, 17 b
Perissomyrmex monticola de Andrade , in Baroni Urbani & de Andrade 1993: 90. Holotype worker. Bhutan.
Worker, measurements (mm): TL 4.6, HL 1.12, HW 1.08, SL 0.92, PW 0.64, AL 1.24, GL 1.35, GW 0.96. Indices: CI 96.4 ,, SI 85.2,
Four teeth of anterior margin of clypeus well isolated; median paired teeth large and distinct; lateral paired teeth small and their tip not reaching the level of the bottom of median notch; median notch converted V shape; the bottom of notch not reaching the level of anterior margin of lateral ridge in front of antennal insertion; distance between a median teeth closer than that between a median tooth and a lateral tooth; position of lateral tooth just below in the middle of toruli. Promesonotum forming single raised convex. Propodeal spines long and acute, directing backward and curved upward. Propodeal lobe low and rounded. Following the restriction on anterior articulator portion to mesosoma, sides of petiole almost parallel in dorsal view.
Posterior face of postpetiolar node declined. Head capsule and mesosoma heavily striate. Mandibles very lightly striate. Mesopleural area, propodeum smooth and shining, petiole smooth and shining.
Body bicolored, with dark brown head and mesosoma and reddish gaster, antennae and legs yellowish.
Queen: TL 5.32, HL 1.20, HW 1.20; CI 100, SL 1.00, SI 75, PW 0.84, AL 1.52, GW 1.20, GL 1.56.
Dentition of anterior margin of clypeus and mandible as in worker, but robust and lower. Mesoscutellum overhanging metanotum, metanotum less convex in profile. Petiole as in worker but with low ventral keel and more distinct lateral projection.
Seemingly P. monticola is distinct in having a bicolored body with blackish head and mesosoma and reddish gaster. The species is similar to P. nepalensis in having an inverted V shaped median notch on the anterior clypeal margin. The notch in P. monticola and P. nepalensis is shallower than in P. emarginatus . The bottom of the notch in both species does not reach the level of anterior ridges in front of the antennal insertions. The teeth arrangement of the anterior clypeal margin is similar to that of P. nepalensis as well, showing that the lateral paired teeth are more spaced to the median paired teeth. The shape of the propodeal spines, upward curved profile, also show the similarity in P. monticola and P. nepalensis . According to the key provided by Radochenko (2003) the species is distinct in having abundant short standing hairs on the antenna and legs, but the character is somewhat delicate and P. emarginatus also shows the same pilosity. It seems that the ventral profile of the petiole is more reliable.
Among the three Asian species, the sculpture of P. monticola is the most distinct, and the unsculptured areas on the mesopleuron and propodeum are broadest. The species is known only from the type locality.
Specimens examined: 1 worker, 1 queen,Nobding 41 km O, Wangdi Ph. 2800 m, Bhutan ( NMB ).