Pheidole acutidens ^HNS (Santschi)

Bruchomyrma acutidens ^HNS Santschi 1922e: 249. Combination with Pheidole ^HNS by Wilson 1984b: 327. Types Naturhist. Mus. Basel.

etymology L acutidens ^HNS, sharp-pointed tooth apparently referring to the reduced, acute mandible.

diagnosis An extreme workerless social parasite of Pheidole nitidula ^HNS, with adaptations that make it unique within the genus. Queen: with 9- to 11-segmented antennae and minute, falcate toothless mandibles that taper to needle-sharp points. Male: pupiform, with mandibles vestigial or absent.

measurements (mm) Syntype queen: HW 0.40, HL 0.42, SL 0.72, EL 0.12, PW 0.58.

Color Queen: yellowish brown.

Range Known only from the type locality.

Biology P. acutidens ^HNS is a permanent workerless parasite of Pheidole nitidula ^HNS. The discoverer of this remarkable species, Carlos Bruch (1931), has provided extensive notes on its anatomy, ecology, behavior, and life cycle.

Figure Queen. ARGENTINA: La Plata, Buenos Aires (Carlos Bruch). Type locality: Alta Gracia (La Granja). Sierra de Cordoba, Argentina. Scale bar = 1 mm.