Pheidole unicornis ^HNS new species

TYPES Mus. Comp. Zool. Harvard.

Etymology L unicornis ^HNS, one-horned, referring to the raised clypeal carina.

diagnosis Similar to binasifer ^HNS, diabolus ^HNS, gravida ^HNS, mirabilis ^HNS, moseni ^HNS, mosenopsis ^HNS, nasifer ^HNS, and rhinoceros ^HNS, and distinguished as follows.

Major: median carina of clypeus raised as a low, forward-projecting lobe; humerus in dorsal-oblique view a low lobe; mesonotal convexity suppressed; propodeal spines vertical on propodeal basal face, and in dorsal-oblique view curve slightly forward; dorsum of propodeum and anterior and lateral margins of pronotal dorsum carinulate; petiolar node in side view symmetrically rounded; postpetiole from above diamond-shaped.

Minor: occiput broad, lacking nuchal collar; posterior half of dorsal head surface smooth and shiny, and anterior half covered mostly by circular carinulae; propodeal spines vertical on propodeal dorsal face; postpetiolar node in side view suppressed; mesosomal pilosity consists of relatively short, erect bristles of nearly equal length.

measurements (mm) Holotype major: HW 1.42, HL 1.64, SL 0.72, EL 0.18, PW 0.84.

Paratype minor: HW 0.72, HL 0.78, SL 0.64, EL 0.12, PW 0.46.

color Major: head medium reddish brown, mandibles and body dark reddish brown; other appendages light reddish brown. Minor: body medium reddish brown, appendages dark yellow.

range Known from the type locality, as well as Pichinde, also near Cali, at 1600 m; and near Cochancay, on Guayaquil-Tambo Highway, Canar, Ecuador.

Biology Occurs in mountain forests.

figure Upper: holotype, major. Lower: paratype, minor. COLOMBIA: Television Tower Road, Salidito, near Cali, 2100 m (W. L. Brown and R. B. Root). Scale bars = 1 mm.