Pheidole scrobifera Emery

Wilson, E. O., 2003, Pheidole in the New World. A dominant, hyperdiverse ant genus., Cambridge, MA: Harvard University Press : 629

Pheidole scrobifera Emery

Pheidole scrobifera Emery 1896g: 73.

Types Mus. Civ. Stor. Nat. Genova.

etymology L scrobifera , trench-bearer, alluding to the antennal scrobes.

diagnosis Distinguished from other members of the scrobifera group as follows.

Major: pilosity very short, absent on anterior half of dorsal profile of head and present as uniform, suberect hairs along the posterior half of the profile; entire dorsal head surface posterior to the eyes rugoreticulate; promesonotal sculpturing consisting entirely of foveolation; petiolar and postpetiolar nodes entirely smooth and shiny; head capsule with bilateral dark spots. Minor: humerus cornulate; propodeal spines long and slender; dorsal head surface and all of mesosoma foveolate, with no carinulae or rugulae anywhere on the body.

Measurements (mm) Major (La Selva Biological Station, Costa Rica): HW 0.88, HL 1.08, SL 0.42, EL 0.14, PW 0.54. Minor (La Selva Biological Station): HW 0.44, HL 0.46, SL 0.36, EL 0.10, PW 0.30.

Color Major: head and mandibles light reddish brown, with bilateral dark brown spots on the dorsal surface, as illustrated; mesosoma a slightly lighter shade of light reddish brown; waist, gaster, legs, and antennae brownish yellow. Minor: head and mesosoma dark, slightly reddish yellow; appendages clear medium yellow.

Range Atlantic slope of Costa Rica to 900 m (J. T. Longino 1997).

Biology According to Longino (1997), as well as Stefan Cover and James C. Trager (independent field notes), scrobifera is relatively common in mature wet forest, nesting in rotten logs and other pieces of rotten wood on the forest floor. Workers have been observed foraging at night.

Figure Upper: major (right hind femur shown at bottom). Lower: minor. COSTA RICA: La Selva Biological Station, near Puerto Viejo (Stefan Cover). (Type locality: Jimenez, near Guapiles, Costa Rica.) Scale bars = 1 mm.