Pheidole in the New World. A dominant, hyperdiverse ant genus. Author Wilson, E. O. text 2003 Harvard University Press Cambridge, MA http://atbi.biosci.ohio-state.edu/HymOnline/reference-full.html?id=20017 book 20017 Pheidole cavifrons Emery Pheidole cavifrons Emery 1906c: 144. Syn.: Pheidole arciruga Forel 1908h: 381, n. syn. Types Mus. Civ. Stor. Nat. Genova. Etymology l cavifrons , hollow front, evidently referring to the deep antennal scrobes. Diagnosis Closest to longior , somewhat less similar to aberrans and 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. Range Recorded from Buenos Aires, Argentina; Uruguay; and Rio Grande do Sul and Parana, Brazil. biology The type colony of synonymous " arciruga " was collected from a termite mound in Rio Grande do Sul. figure Upper: lectotype, major (La Sierra, Uruguay). Lower: minor (" arciruga " syntype, Rio Grande do Sul, Brazil, compared with cavifrons paralectotype). Scale bars = 1 mm.