Pheidole arctos ^HNS new species

Types Mus. Comp. Zool. Harvard.

etymology Gr arctos ^HNS, bear, alluding to the large size and rough, shaggy appearance of the major.

Diagnosis Close to gangamon ^HNS, also of Mexico, and probably also to epetrion ^HNS and thrasys ^HNS, but distinguished from these and other members of the scrobifera ^HNS group by the following combination of traits.

Major: rear one-fourth of dorsal head surface, rear one-half of the lateral head surfaces, and area between the eye and frontal lobes rugoreticulate; anterior half of the frontal lobes carinulate; entire central half of the dorsal head surface foveolate only; all of promesonotal and postpetiolar dorsa carinulate to rugoreticulate; anterior central strip of first gastral tergite longitudinally striate; humerus composing a very large lobe that projects high above the mesonotal convexity; posterior half of dorsal head profile weakly concave.

Minor: the two humeri conulate, the tip of each bearing very long hairs; head and prothorax entirely smooth and shiny.

Measurements (mm) Holotype major: HW 1.28, HL 1.60, SL 0.62, EL 0.18, PW 0.82.

Paratype minor: HW 0.62, HL 0.64, SL 0.60, EL 0.12, PW 0.42.

Color Major and minor: body dark brown, appendages medium brown, tarsi yellow.

Range Known only from the type locality.

Biology Unknown.

Figure Upper: holotype, major. Lower: paratype, minor. MEXICO: Gomez Farias, Tamaulipas, 400-600 m (Cornell University Mexico Field Party, 1964). Scale bars = 1 mm.