Trachymyrmex intermedius (Forel 1909)

Attini, Myrmicinae, Formicidae, Hymenoptera, Insecta, Arthropoda, Animalia

worker face view

worker lateral view


Guatemala (type locality), Honduras, Mexico, Costa Rica. Costa Rica: Atlantic lowlands, mid-elevation Pacific slope of Cordillera de Tilaran.


Preorbital carina curved inward, arcing obliquely toward frontal carina; propodeal spines long, much longer than other tubercles on dorsal face of propodeum; scapes long, extending well beyond margin of vertex; color orange brown; promesonotum with four principal pairs of spines.

Similar species: JTL-004.

Natural History

Trachymyrmex intermedius inhabits wet and moist forest habitats. It seems to prefer relatively open areas with a thin litter layer. Nests are in the soil, with a spherical chamber just beneath the surface. The chamber is approximately 5cm diameter, containing a spongy white fungus garden.

At La Selva Biological Station it is relatively common in the laboratory clearing. Various attine researchers, including Jim Wetterer and Ted Schultz, have excavated colonies in the clearing. Azur Moulaert found workers cutting leaves of Callophyllum brasiliense in the open second growth of the La Guaria Annex of La Selva. I have collected ground foragers on the grounds of an ecotourism lodge in Tortuguero and in scrubby second growth forest at 800m on the Pacific slope below Monteverde.

Like Trachymyrmex in general, the species is extremely rare in Winkler samples of sifted litter, suggesting that it avoids areas of deep leaf litter or is poorly sampled by Winkler sifting for some other reason.


Atta (Trachymyrmex) intermedius Forel 1909:249. Worker: Guatemala. Combination in Trachymyrmex: Kempf, 1972:253.


Jeffry Sossa examined the types of T. cornetzi and T. intermedius, and kindly pointed out that I had misidentified T. intermedius as T. cornetzi, and that what I had been calling morphospecies JTL-001 was probably T. cornetzi. I have fixed those errors with this version of the page.

Page author:

John T. Longino, The Evergreen State College, Olympia WA 98505

Date of this version: 1 March 2007.
Previous versions of this page: 5 January 2004.
Go back to top

Go to Ants of Costa Rica Homepage