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 obscurior
Forel,
new status
Pheidole susannae r. obscurior
Forel 1886b: xliv. Syn.:
Pheidole partita Mayr
1887: 590,
n. syn.
Types Mus. Hist. Nat. Geneve.
etymology L
obscurior
, darker, presumably in comparison to the yellow
susannae
.
diagnosis A member of the
fallax
group, closest to
susannae
but also resembling
haskinsorum
,
lattkei
, and
petrensis
, and distinguished as follows.
Major: color mostly light to medium brown; head sometimes bicolorous, as illustrated, and described below; antennal scape reaching slightly beyond occipital comer; rugoreticulum extensive around eye but not laterad to it; humerus subangulate in dorsal-oblique view; pronotum carinulate; mesosoma and waist entirely foveolate and opaque, but first gastral tergite entirely smooth and shiny; petiolar node in side view tapering to a blunt point. Minor: occiput moderately narrowed, with nuchal collar.
measurements (mm) Lectotype major: HW 1.32, HL 1.44, SL 1.04, EL 0.20, PW 0.64.
Paralectotype minor: HW 0.60, HL 0.80, SL 1.02, EL 0.16, PW 0.44.
Color Major: light to medium reddish brown, with reddish tinge very slight.
Minor: concolorous brownish yellow.
Range Reported by Kempf (1972b) from Santa Fe and Misiones, Argentina; southeastern Brazil; Colombia; Trinidad; St. Vincent; Costa Rica; and Guatemala. I have been able to verify series from Rio de Janeiro, Sao Paulo, and Meta, Colombia.
Biology Colonies collected by H. H. Smith on St. Vincent and identified by Forel (1893j) as
obscurior
were in logs and other pieces of rotten wood in or near forests. They were populous, containing 500-1000 individuals, and aggressive when disturbed. The species was considered by Smith to be rare. He found winged queens and males in nests in early November.
figure Upper: major. Lower: minor. BRAZIL: Caraguatatuba Reserva Floresta, Sao Paulo, 40-80 m (William L. Brown). Major and minor compared with lectotype and paralectotype by E. O. Wilson. (Type locality: Guanabara, Rio de Janeiro, Brazil.) Scale bars = 1 mm.