Pheidole humeridens new species

Types Mus. Comp. Zool. Harvard.

etymology L humeridens, shoulder-tooth.

Diagnosis A member of the fallax group similar in various characters to the species listed above, differing as follows. Major: humerus dentate; rugoreticulum on sides of head extends to halfway between eyes and level of occiput; mid-occiput transversely carinulate; antennal scapes reach halfway between eyes and level of occiput; anterior edge of pronotum and all of propodeal dorsum transversely carinulate; in side view, propodeal spines short, vertical to basal propodeal face; from above, postpetiole oval.

Minor: bicolored (see below); humerus toothed; propodeal tooth small and thin; propodeal dorsum carinulate; occiput in full-face view flat.

Measurements (mm) Holotype major: HW 1.50, HL 1.56, SL 1.02, EL 0.26, PW 0.78. Paratype minor: HW 0.74, HL 0.80, SL 0.94, EL 0.20, PW 0.46.

COLOR Major: brownish yellow, with rear halves of gastral tergites changing to light brown..

Minor: bicolored, with head, gaster, and pronotal dorsum medium brown, and rest of body and appendages brownish yellow.

range Known only from the type locality.

Biology At the type locality humeridens colonies occupied conspicuous mound nests in a heavily grazed pasture.

Figure Upper: holotype, major. Lower: paratype, minor. ARGENTINA: Buenos Aires (James C. Trager). Scale bars = 1 mm.