Pheidole colobopsis Mann 1916

= Pheidole JTL-111 Longino ms.
= Pheidole JTL-124 Longino ms.

Myrmicinae, Formicidae, Hymenoptera, Insecta, Arthropoda, Animalia

worker face view

worker lateral view

major face view

major lateral view

major face view

Identification

Minor worker: head length 0.54mm, head width 0.52mm, scape length 0.51mm, Webers length 0.68mm (n=1). Head somewhat cordate behind; promesonotum evenly arched, mesonotal suture absent; propodeal spines very short, upturned; scapes foveolate; clypeus longitudinally rugose; frontal carinae elevated, flange-like anteriorly; face and most of mesosoma uniformly foveolate, overlain with a silky luster and violaceous reflections; side of pronotum smooth and shining; first gastral tergum largely smooth and shining, but also with silky luster and violaceous reflections, and anterior fourth with feeble clathrate sculpture; dorsal pilosity moderately abundant, moderately long, flexuous; color red brown.

San Vito specimen: head length 0.64mm, head width 0.60mm, scape length 0.55mm, Webers length 0.81mm (n=1). Face weakly foveolate, overlain with longtitudinal branching rugae originating just medial to frontal carinae and extending nearly to lateral vertex margins.

Major worker: strongly phragmotic head.

The queen is also phragmotic.

Range

Brazil (Rondonia), Colombia, Costa Rica. Costa Rica: Atlantic slope, southern Pacific mountains (San Vito area).

Natural History

This species inhabits forest floor leaf litter in wet forest habitats. Minor workers have been collected in a Berlese sample from La Selva, a Winkler sample from Turrialba, a Winkler sample from 880m elevation on the Barva transect in Braulio Carrillo National Park, and a collection by L. and A. Alonso from near San Vito.

The holotype is a queen that Mann collected beneath dead wood on the ground. A Peruvian colony was collected from clay soil at the base of a rainforest tree. The nest was 12cm deep and contained a single queen five soldiers, and about 200 minors (Wilson 2003).

The Conservation International TEAM project at La Selva recently obtained a soldier of this species associated with minor workers, which confirmed its identity as colobopsis. The soldier has mud caked in the concavities on each side of the antennal insertions. It makes me wonder whether these deep concavities and coarse striae on the mandibles and anterior face function to hold a cap of soil, such that when a soldier is blocking the nest entrance it is completely hidden from view. From the outside there would be an even soil surface, with neither visual nor tactile (and perhaps less olfactory) evidence of a nest entrance.


Page authors:

John T. Longino, The Evergreen State College, Olympia WA 98505 USA. longinoj@evergreen.edu

Stefan Cover, Museum of Comparative Zoology, Harvard University, Cambridge MA 02138 USA. scover@oeb.harvard.edu


Date of this version: 26 July 2005.
Previous versions of this page: 7 October 2003, 8 December 1997, Pheidole JTL-124 page.
Go back to top

Go to Ants of Costa Rica Homepage