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 setsukoae new species Types Mus. Comp. Zool. Harvard. Etymology Named after Barbara Setsuko Hamton. diagnosis A member of the pilifera group uniquely distinguished within not just Pheidole but ants as a whole by the phragmotic condition of the occiput of the major, as illustrated. Also distinctive in the major, although not unique, are the lack of hypostomal dentition; the high, smoothly rounded outline of the promesonotum in side view; the dense parallel longitudinal carinulae that radiate from the antennal fossae and antennal lobes to the sides of the head; and the conulate postpetiolar node. The minor is typical of the " bicarinata complex" (see under bicarinata ). measurements (mm) Holotype major: HW 1.38, HL 1.54, SL 0.62, EL 0.14, PW 0.76. Paratype minor: HW 0.50, HL 0.54, SL 0.60, EL 0.12, PW 0.30. color Major: concolorous clear yellow with a very slight orange tinge ("light orange"). Minor: clear medium yellow; dorsal surface of head slightly infuscated, i.e., dark yellow to light brownish yellow. Range Known only from the type locality. biology Robert J. Hamton (in litt. 1990): the majors and minors were foraging in a single file to dead moths at a blacklight (ultraviolet light used to attract insects). Figure Upper: holotype, major. Lower: paratype, minor. MEXICO: 59 km north of Culiacan, Sinaloa (Robert J. Hamton). Scale bars = 1 mm.