Perissomyrmex snyderi Smith

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 : 362

Perissomyrmex snyderi Smith , M. R.

Figures 16 g, h, 17 d

Perissomyrmex snyderi Smith , M. R. 1947: 282. Holotype worker. Guatemala.

Diagnosis.

Worker, TL 3.74 - 4.94, HL 0.88 - 1.24, HW 0.88 - 1.34, CI 100 - 108, SL 0.82 - 0.94, SI 73 - 93, PW 0.56 - 0.72, ML 0.98 - 1.20, GL 1.00 - 1.40, GW 0.80 - 1.06.

Polymorphic. Labrum with lamellate flange developed at basal part of curvature. Anterior clypeal margin with 3 pairs of projection, the shape and size varying to reduce or fused; basically, the median pair broad and robust, inner lateral pair smaller; outer lateral pair smallest, sometimes reduced or lost; the median notch roundly concave; in some case the median paired teeth fused without median notch in major worker. Propodeal spine straight or slightly curved upward. Subpetiolar process present anteriorly; ventral margin of petiole almost straight in profile; anterior portion of petiole diverging toward midlength of petiole in dorsal view. Sculpture on head and mesosoma irregularly costate. Body color blackish.

Specimens examined: 9 workers (including 1 major), 4 km N Union Juarez , Volcan Tacann , Lower slopes 1950 m, Chiapas, Mexico (4 in UCD, 5 in BMNH).

Remarks

The species shows great variation in worker caste body size, the shape of spines and the teeth on the anterior clypeal margin, but the subpetiolar process is consistently present, which is unique among the four Perissomyrmex species. In addition, P. snyderi is also unique in having coarser and more irregular sculptures on the head and mesosoma and dark color of the body. The degree of the protuberance of the anterior clypeal margin is less distinct than that in Asian species, even though variation exists.

The rediscovered individuals were collected from Berlese samples of a cloud forest floor of 1700 to 2000 m altitude in Chiapas, Mexico (Longino & Hartley, 1995).