Pheidole barbata

From Wilson (2003): According to Creighton and Gregg (1955), barbata is a desert species, which prefers to nest in light, sandy soil, although it also lives in coarse, hard-packed sand along the edges of arroyos. The nest is surmounted by a low crater 5-10 cm in diameter, and it is sometimes also surrounded by a chaff ring, suggesting that barbata is a harvester ant. Colonies excavated by Creighton comprised up to 11 majors and 73 minors, although this may be an underestimate of the real population size, since no nest queen was ever found. Similar nest structures were encountered in Deep Canyon, near Palm Springs, California, by G. C. and J. N. Wheeler (1973e).

Identification
See the description in the nomenclature section.

Distribution
From Wilson (2003): Western Arizona, southern Nevada, and southeastern California (Creighton and Gregg 1955; G.C. and J. N. Wheeler 1973e, 1986g).

Distribution based on Regional Taxon Lists
Nearctic Region: United States. Neotropical Region: Mexico.

Worker
Minor

Nomenclature

 *  barbata. Pheidole barbata Wheeler, W.M. 1908e: 448 (s.w.) U.S.A. See also: Wilson, 2003: 560.

Description
DIAGNOSIS From Wilson (2003): A member of the “bicarinata subgroup” of the larger pilifera group, which subgroup comprises Pheidole agricola, Pheidole aurea, Pheidole barbata, Pheidole bicarinata, Pheidole centeotl, Pheidole cerebrosior, Pheidole defecta, Pheidole gilvescens, Pheidole macclendoni, Pheidole macrops, Pheidole marcidula, Pheidole paiute, Pheidole pinealis, Pheidole psammophila, Pheidole xerophila, Pheidole yaqui and Pheidole yucatana (barbata is closest to psammophila); and is characterized by the large, forward-set eyes of both castes; and, in the major, the occipital lobes lacking any sculpturing (except in ''aurea'), the posterior half of the head capsule almost entirely smooth and shiny; and the postpetiolar node seen from above oval, elliptical, or laterally angulate (rarely cornulate, never spinose). P. barbata is distinguished by the absence of propodeal spines in both castes. Further: in the major, teeth absent on the hypostoma; humerus very prominently lobose in dorsal-oblique view; and spinose subpetiolar process seen in side view. Minor: very long coarse hairs (psammophore?) line the ventral surface of the head; petiolar and postpetiolar nodes very low.

MEASUREMENTS (mm) Major (Rancho Dos Palmas, California): HW 1.62, HL 1.72, SL 0.74, EL 0.26, PW 0.72. Syntype minor: HW 0.44, HL 0.54, SL 0.52, EL 0.18, PW 0.30.

COLOR Major: head brownish yellow, with occiput and area around midcenter line light brown; mesosoma, waist, and antennae brownish yellow; legs medium yellow.

Minor: concolorous light yellowish brown.



'''Figure. Upper: major. CALIFORNIA: Rancho Dos Palmas, east of the Salton Sea. Lower: minor, syntype. Scale bars = 1 mm.'''

Type Material
Mojave Desert near Needles, San Bernadino Co. and  - as reported in Wilson (2003)

Etymology
L barbata, bearded, alluding to the long, coarse hairs on the ventral head surface of the minor. (Wilson 2003)