Ants of Cerro Platano

Ants of Cerro Platano, Costa Rica

Report by John T. Longino and Michael G. Branstetter, The University of Utah. Student participants: Irene Calderon, Josue Corrales, Krissy Dominguez, Scott Heacox, Josh Kouri, Irene Mata, Mac Pierce, Marianela Solís.

This is a list of the ants of Cerro Platano, Costa Rica, based on Project ADMAC sampling. Cerro Platano is on the Atlantic slope between Cerro Chirripó and Limón, at 1100 m elevation. It is mature cloud forest on a narrow ridge.

Project ADMAC carried out ant sampling at Cerro Platano from 15-19 June 2015. Conditions were extremely wet. A storm system moved in the day after we arrived. It rained heavily for at least part of every day, sometimes the entire day. We were able to do the first 37 miniWinkler samples on 16 June, but then had to wait until 18 June to finish the transects. Thus samples 38-100 were only able to hang for one and a half days. Elevation of collecting sites varied from 980 m to 1140 m, all within a km of each other. The upper elevation was a small local peak, with ridges sloping downwards in all directions. The peak was cloud forest, but the lower forest, around 1000 m, had a somewhat more lowland aspect.

Specimen records have been uploaded to the AntWeb database and are periodically updated. Names in the species list are linked to individual specimen records on AntWeb, from which a link can be followed to the general species page. These specimens function as site-specific vouchers, whose identities may change. The species names in the list are static text on this page. Following the specimen link to AntWeb will allow one to see if the name has changed.

There are at least 161 species. Notable discoveries include:

The third specimen of an unusual Camponotus, currently undescribed and previously known from Braulio Carrillo National Park.

Multiple specimens of the rare Cyphomyrmex snellingi, previously known from two workers from the type locality in Panama, one worker from Braulio Carrillo National Park, and one worker from near Monteverde.

A second worker of Gnamptogenys cuneiforma. This distinctive species was known only from the type specimen, from the Bocas del Toro region of Panama, and described in 1994 by John Lattke.

It was gratifying to discover a second population of Myrmelachista flavoguarea, previously known only from the Peñas Blancas valley east of Monteverde. This species is a specialist plant ant found only in live stems of understory treelets of the genus Guarea (Meliaceae).

An impressive fauna of the mega-genus Pheidole was found: 40 species! Nine of these are undescribed morphospecies, four of which were found for the first time at Cerro Platano.