Pheidole bison new species

Types Mus. Comp. Zool. Harvard.

etymology L Gr bison, the wisent (European bison), alluding to the massive humped back of the major.

diagnosis A medium-sized member of the tristis group similar to bellatrix, napoensis, and pullula, differing as follows. Major: promesonotum a single massive piece, its dorsal border forming a single convexity that drops vertically at the rear to the metanotum; head entirely covered with longitudinal carinulae except for frontal triangle and central section of clypeus; space between eye and antennal fossa rugoreticulate; petiolar node in side view tapered apically to a blunt point; postpetiolar node from above trapezoidal.

Minor: almost all of head and mesosoma foveolate and opaque; irregular broken rugulae present on posterior dorsal head surface; propodeal spines reduced to denticles; occiput broad, weakly concave.

Measurements (mm) Holotype major: HW 1.26, HL 1.30, SL 0.76, EL 0.12, PW 0.60.

Paratype minor: HW 0.62, HL 0.64, SL 0.64, EL 0.08, PW 0.44.

COLOR Major: head dark reddish brown, rest of body medium reddish brown, appendages light reddish brown. Minor: concolorous brownish yellow.

Range Known only from the type locality.

Biology The type series was collected by Philip S. Ward from a termite nest in savanna.

Figure Upper: holotype, major. Lower: paratype minor. BOLIVIA: La Games, Parque Nacional Noel Kempff Mercado, Santa Cruz, 14°48'S 60o23W, 700 m (Philip S. Ward). Scale bars = 1 mm.