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 heterothrix Santschi, new status Pheidole obtusopilosa st. heterothrix Santschi 1923d: 59. Syn.: Pheidole gavrilovi Kusnezov 1952d: 80, n. syn. types Naturhist. Mus. Basel. Etymology Gr heterothrix , different hair (from that of obtusopilosa ). Diagnosis Similar to obtusopilosa in some traits but distinguished from it and other Pheidole species as follows. Major: patch of rugoreticulum present between eye and antennal fossa on each side; entire remainder of dorsal surface of head, including occiput, carinulate; very faint antennal scrobe present; promesonotal profde smoothly rounded; mesonotal convexity low but with distinct anterior and posterior declivities; all of pronotum carinulate; humeri rugoreticulate; pilosity dense and short; postpetiole from above conulate. Minor: humerus subangulate; propodeal spines robust, moderately long, and directed backward; all of body except gaster foveolate. Measurements (mm) Lectotype major { heterothrix , not " gavrilovi "): HW 1.12, HL 1.16, SL 0.54, EL 0.18, PW 0.62. Paralectotype minor: HW 0.54, HL 0.54, SL 0.44, EL 0.10, PW 0.32. Color Major: all of body light reddish brown except gaster, which is medium reddish brown. Minor: body dark reddish brown, appendages medium reddish brown. range In addition to the types, from Villaguay, Entre Rios, Argentina, I have seen series from the Argentine provinces of La Pampa, Misiones, and Tucuman. Biology One series, collected by W. L. Brown at Horco Molle, Tucuman, was found at 900-1150 m in myrtaceous forest. Figure Upper: major (syntype of synonymous gavrilovi ). Lower: minor (syntype of synonymous gavrilovi ). ARGENTINA: Loreto, Misiones, Argentina. Compared with lectotype and paralectotype of heterothrix ; upper outlines of minor mesosoma and occiput are those of heterothrix syntype. (Type locality of heterothrix : Villaguay, Entre Rios, Argentina.) Scale bars = 1 mm.