Platythyrea pilosula (F. Smith 1858)

Formicidae, Hymenoptera, Insecta, Arthropoda, Animalia

worker face view

worker lateral view


Costa Rica to northern Argentina east of the Andes. Costa Rica: lowland wet forest, especially on Atlantic side.


Masticatory margin of mandible edentate; petiole length (dorsal view) greater than 0.85mm.

Natural History

My collections of this species have mostly been individuals captured on tree trunks and low vegetation. The workers are very fast and difficult to capture. I observed one nest in a recently felled Virola tree at La Selva Biological Station. It was in and under an epiphyte mat, extending into small chambers in the bark. I have collected alate queens twice, one on the northern slope of Volcan Barba, at 500m elevation (at the El Ceibo station, near the crossing of the Rio Peje) on 14 July 1986, and another in the Peľas Blancas Valley on 27 April 1987. I collected a dealate queen that was a nocturnal forager, running with a nymph of Tingidae in its mandibles.

In Costa Rica, I have seen collections from Hitoy Cerere Biological Reserve, La Selva Biological Station, Braulio Carrillo National Park and vicinity to 600m, the Penas Blancas Valley east of Monteverde, Guacimal on the Pacific slope below Monteverde, and Carara Biological Reserve.


Platythyrea pilosula and punctata form part of the punctata complex, of which Brown (1975) wrote:

[The species of the punctata complex] are both very close and highly variable, so that species limits are anything but clear. In fact, it is possible that most or all of these forms are variants, in part geographically distributed, of a single species that should bear the prior name P. pilosula. In this work, I have adopted a more conservative course, provisionally recognizing 5 species in the complex even though no one of them can be cleanly separated from all of the other 4.

One of the species he recognized was P. sinuata (Roger 1860), which differed from pilosula by having a curved sulcus at the base of the mandible. Most Costa Rican material I have seen has the sulcus, but a few lack it, and there is a high degree of variation. The mandibular sulcus varies from strongly marked to weakly marked to absent. One specimen has the sulcus on one mandible and lacks it on the other. Thus I now treat sinuata as a junior synonym of pilosula.

Type data

Ponera pilosula F. Smith 1858:95. Syntype worker: Brazil.

Ponera sinuata Roger 1860:297. Syntype worker, male: Suriname.

Literature Cited

Brown, W. L., Jr. 1975. Contributions toward a reclassification of the Formicidae. V. Ponerinae, tribes Platythyreini, Cerapachyini, Cylindromyrmecini, Acanthostichini, and Aenictogitini. Search, Agriculture, Cornell University 5:1-116.

Roger, J. 1860. Die Ponera-artigen Ameisen. Berl. Entomol. Z. 4:278-312.

Smith, F. 1858. Catalogue of hymenopterous insects in the collection of the British Museum. Part VI. Formicidae. London: British Museum, 216 pp.

Page author:

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

Date of this version: 16 December 2003.
Previous versions of this page: 31 May 1999
Go back to top

Go to Ants of Costa Rica Homepage