Pheidole psilogaster

This species occurs in wet forest habitats from sea level to 1400m elevation. It is known mainly from baits on the forest floor, and occasionally workers occur in Winkler and Berlese samples. Major workers often recruit to baits along with minor workers. D. J. Cox collected a nest in standing dead wood. The type colony was collected from sifted litter, leaf mold, and rotting wood in a rainforest. (Wilson 2003, Longino 2009)

Identification
See the description in the nomenclature section.

Distribution
Southern Mexico to Costa Rica.

This taxon was described from Mexico.

Nomenclature

 *  psilogaster. Pheidole psilogaster Wilson, 2003: 341, figs. (s.w.) MEXICO. See also: Longino, 2009: 66.

Description
A member of the fallax group, very similar to Pheidole potosiana and less so to Pheidole acamata, Pheidole cielana, Pheidole cockerelli, Pheidole dione, Pheidole hyatti and Pheidole midas.

Major: first gastral tergite covered with short recumbent hairs of even length, and anterior half also by a dense layer of short subrecumbent hairs all of approximately the same length; gastral sternites covered by dense subrecumbent hairs all of which are the same medium length; head and body concolorous light reddish brown; mesopleuron with broken short rugulae; rugoreticulum on head stretches on each side from eye to antennal fossa; carinulae extend posteriorly to eye only a little more than 2X Eye Length, except for those adjacent to midline, which travel from vertex to occiput; humerus in dorsal-oblique view subangulate.

Minor: occiput narrowed with nuchal collar; humerus in dorsal-oblique view denticulate; propodeal spines thin and vertical to basal propodeal space; mesopleuron carinulate. MEASUREMENTS (mm) Holotype major: HW 0.94, HL 1.00, SL 0.82, EL 0.16, PW 0.52. Paratype minor: HW 0.58, HL 0.70, SL 0.90, EL 0.12, PW 0.38.

COLOR Major: concolorous light reddish brown.

Minor: body concolorous plain medium brown; appendages light to yellowish brown except for tarsi, which are yellow.



'''Figure. Upper: holotype, major. Lower: paratype, minor (tentatively associated). Scale bars = 1 mm.'''

Type Locality Information
MEXICO: Los Tuxtlas, 10 km north-northwest of Sontecomapan, Veracruz, 500 m, col. Philip S. Ward.

Etymology
Gr psilogaster, bare stomach (gaster of ant).