This is a common dry forest species in northwest Costa Rica. Colonies can occur in very open, disturbed areas. For example, they have been observed in the central city park of Liberia. Workers are seed harvesters, and form conspicuous trunk trails to seed sources. They are also generalist foragers and will readily come to baits. Diurnal and nocturnal foraging have been observed. The nests are in bare soil, with conspicuous nest entrances and chaff piles. Workers have a foetid odor when collected. In Santa Rosa National Park, Longino once observed a colony emigration: a thick column of alate queens and brood-carrying workers extended many meters along the edge of a dirt road.
Widespread in the Neotropics from Nicaragua to Argentina, and on Caribbean islands. Costa Rica: common in northwest (dry forest habitats).
Taxonomic history
Forel, 1881 PDF: 9 (w.); Goñi et al., 1984 PDF: 365 (k.).Senior synonym of Pheidole fallax rubens: Forel, 1901j PDF: 356.Senior synonym of Pheidole fallax britoi: Wilson, 2003a: 290.Senior synonym of Pheidole columbica: Wilson, 2003a: 290.Senior synonym of Pheidole jelskii fallacior: Wilson, 2003a: 290.Senior synonym of Pheidole fallax ovalis: Wilson, 2003a: 290.Canindeyú , Pte. Hayes (ALWC).
Literature records: Pte. Hayes, “Paraguay” (s. loc.) (Fowler 1981, Kempf 1972).
Pheidole fallax is a Central American/Caribbean species highly unlikely to be conspecific with southern South American forms; Wilson (2003) gives distribution. Records probably refer to P. jelskii or P. obscurithorax .
