Pheidole torosa, Wilson, E. O., 2003

Wilson, E. O., 2003, Pheidole in the New World. A dominant, hyperdiverse ant genus., Cambridge, MA: Harvard University Press : 603

Pheidole torosa new species

Types Mus. Comp. Zool. Harvard.

Etymology L torosa , muscular, bulging, a reference to the major caste.

diagnosis A member of the " pilifera complex" of the larger pilifera group, comprising calens , californica , carrolli , cavigenis , clementensis , creightoni , hoplitica , littoralis , micula , pilifera , polymorpha , rugulosa , senex , soritis , tepicana , and torosa , which complex is distinguished by the following traits. Major: dorsal head surface extensively sculptured; occipital lobe transversely rugulose (or, in carrolli smooth, in littoralis foveate, and in micula and soritis carinulate); postpetiole from above diamond-shaped, trapezoidal, or spinose. Minor: eye medium-sized to large. P. torosa is distinguished within the complex as follows.

Major: bicolorous; transverse rugulae cover posterior fifth of dorsal surface of head in full-face view, and longitudinal carinulae cover all of the remainder of the dorsal surface except the frontal triangle; humerus in dorsal-oblique view prominent and lobose; in side view, mesonotum drops almost vertically to metanotum; propodeal spines very long, stout, and vertical to propodeal basal face; seen from above, postpetiole very wide relative to petiole, and spinose.

Minor: all of head and mesosoma foveolate and opaque; pilosity along promesonotal dorsum consists of evenly spaced pairs of setae.

This species is very close to and possibly synonymous with senex .

Measurements (mm) Holotype major: HW 1.56, HL 1.84, SL 0.76, EL 0.20, PW 0.68.

Paratype minor: HW 0.58, HL 0.64, SL 0.62, EL 0.14, PW 0.32.

color Major: bicolorous, with light reddish brown head and appendages contrasting with dark brown mesosoma and gaster.

Minor: concolorous light brown.

Range Known only from the type locality.

Biology Unknown.

Figure Upper: holotype, major. Lower: paratype, minor. MEXICO: El Sueco, Chihuahua. Scale bars = 1 mm.