Pheidole piceonigra Emery

Wilson, E. O., 2003, Pheidole in the New World. A dominant, hyperdiverse ant genus., Cambridge, MA, USA: Harvard University Press : 216

Pheidole piceonigra Emery

Types Naturhist. Mus. Wien (unde rpicea Mayr).

Etymology L piceonigra , pitch-black plus black.

Diagnosis Close to indistincta of Costa Rica, considered by Longino (1997) to belong with it in a single, very variable species. The types, however, are very different, with those of piceonigra distinguished as follows.

Major: piceonigra with much less abundant pilosity than indistincta ; rugoreticulation between eye and antennal fossa; color much darker (see Color below), and head concolorous, not bicolorous as in indistincta ; posterior side of head with bands of foveolae; humerus in dorsal-oblique view rounded; apex of postpetiole in side view more rounded.

Minor: occiput and posterior sides of head foveolate, not smooth as in indistincta ; much less pilose than indistincta ; color much lighter.

If continuous intergrades are demonstrated between the two forms, they may be joined; otherwise it is more prudent to distinguish them as species.

Measurements (mm) Lectotype major: HW 1.06, HL 1.04, SL 0.76, EL 0.20, PW 0.54. Paralectotype minor: HW 0.62, HL 0.70, SL 0.80, EL 0.14, PW 0.40. Color Major: body dark brown, gaster almost black.

Minor: head, mesosoma, and waist dark reddish brown; propodeum and gaster blackish brown; appendages medium brown.

Range I have seen series from Chiapas, Tamaulipas, and Veracruz in Mexico, at 1070-2200 m, and from Costa Rica. On the basis of the types, I am considering this species as different from indistincta , which also occurs in Costa Rica.

Biology Longino's notes (1997) on the distribution and natural history of " indistincta " may apply to that species, to piceonigra , or to both. I found a large, undoubted piceonigra colony nesting at the base of an ornamental shrub in a much disturbed San Jose city park. In Tamaulipas, the Cornell University Mexico Field Party of 1965 encountered it at 1070 m in tall cloud forest.

Figure Upper: lectotype, major. Lower: paralectotype, minor. MEXICO (no further data). Scale bars = 1 mm.