Pheidole cavifrons

The type colony of synonymous arciruga was collected from a termite mound in Rio Grande do Sul. (Wilson 2003)

Identification
See the description in the nomenclature section.

Distribution
Recorded from Buenos Aires, Argentina; Uruguay; and Rio Grande do Sul and Paraná, Brazil. (Wilson 2003)

Distribution based on Regional Taxon Lists
Neotropical Region: Argentina, Brazil, Uruguay.

Nomenclature

 *  cavifrons. Pheidole cavifrons Emery, 1906c: 144, fig. 21 (s.w.) URUGUAY. Combination in P. (Elasmopheidole): Emery, 1915i: 190. Senior synonym of fuscipunctis: Gallardo, 1932c: 182; of arciruga: Wilson, 2003: 132.
 * arciruga. Pheidole arciruga Forel, 1908c: 381 (w.) BRAZIL. Combination in P. (Elasmopheidole): Bruch, 1914: 219. Junior synonym of cavifrons: Wilson, 2003: 132.
 * fuscipunctis. Pheidole (Elasmopheidole) cavifrons var. fuscipunctis Santschi, 1916e: 374, fig. (s.w.q.) ARGENTINA. Junior synonym of cavifrons: Gallardo, 1932c: 182.

Description
From Wilson (2003): Closest to Pheidole longior, somewhat less similar to Pheidole aberrans and Pheidole obnixa, distinguished as follows.

Major: head markedly elongate (Head Length/Head Width 1.39); concolorous yellow; hypostoma toothless; dorsal posterior half of head flat; frontal lobes in full-face view with lobose anterior margins; carinulae originating on frontal lobes end far short of midpoint between eyes and occiput; mesonotal convexity in side view reduced; propodeal spines strongly developed; promesonotum smooth and shiny.

Minor: pronotal dorsum covered by semicircular carinulae.

MEASUREMENTS (mm) Lectotype major: HW 0.76, HL 1.06, SL 0.34, EL 0.06, PW 0.54. Minor: HW 0.46, HL 0.52, SL 0.34, EL 0.04, PW 0.32.

COLOR Major: concolorous medium yellow. Minor: concolorous pale yellow.



'''Figure. Upper: lectotype, major (La Sierra, Uruguay). Lower: minor (arcirug syntype, Rio Grande do Sul, Brazil, compared with cavifrons paralectotype). Scale bars = 1 mm.'''

Type Material
La Sierra, Uruguay. - as reported in Wilson (2003)

Etymology
L cavifrons, hollow front, evidently referring to the deep antennal scrobes. (Wilson 2003)