Formicidae, Hymenoptera, Insecta, Arthropoda, Animalia
Range
Throughout tropical Americas from southern USA to Argentina, and most of the Caribbean islands; also known from southeast Asia and Polynesia, probably as an introduced tramp species from the New World. Costa Rica: bare slopes of Volcan Arenal, Monteverde.
Identification
Eye circular, composed of approximately 5 fused facets; in full face view eyes small enough to not break lateral outline of head; puncta on face dense, closely spaced, face subopaque; petiolar node distinctly quadrate, which distinguishes it from any other species in Costa Rica; color very dark red brown to nearly black. Measurement data.
Natural History
This is a tramp species, typically found in open and highly disturbed areas. I have only collected it once in Costa Rica, but this probably reflects my collecting bias for mature forest habitats. It could be relatively common in open areas.
My one observation was from a weathered but still largely bare lava flow on the slopes of Volcan Arenal, near the Arenal Observatory Lodge. I flipped about 100 stones in an area about 50m from the forest edge. The exposed stones were 10-50cm across, embedded in a sandy soil. The rocks were covered with a thin coating of lichens; otherwise the surface was bare. The only ants I found were nests of opaciceps, but they were relatively frequent, under about 10 of the rocks.
Stefan Cover collected two nests in Monteverde. They were along the road to Penas Blancas, 1/4 mile below the Ventana in the Monteverde Cloud Forest Reserve. They were shallow nests in clay soil at the roadside. One nest series contained a yellow ergatoid male with 13 antennal segments.
Type Data
Ponera opaciceps Mayr 1887:536. Lectotype worker: Brazil, Santa Catarina. Lectotype designated and species redescribed by Kempf (1962).
Literature Cited
Kempf, W. W. 1962. Miscellaneous studies on neotropical ants. II. (Hymenoptera, Formicidae). Studia Entomol. 5:1-38.
Mayr, G. 1887. Sudamerikanische Formiciden. Verhandlungen der zoologische-botanische Gesellschaft Wien 37:511-632.
Page author:
John T. Longino, The Evergreen State College, Olympia WA 98505 USA.longinoj@evergreen.edu