Discothyrea humilis Weber 1939

Formicidae, Hymenoptera, Insecta, Arthropoda, Animalia

worker lateral view

Range

Venezuela, Trinidad, Panama, Costa Rica, Mexico (Chiapas). In Costa Rica I have seen specimens only from the Osa Peninsula region, in spite of extensive collecting elsewhere.

Identification

Antennae 7 segmented; face somewhat shiny, not mat or punctate; interantennal lamella subtriangular in lateral view; lamella relatively smaller compared to JTL-004, a tooth originating between antennal insertions, well above anterior margin of clypeus, such that in side view lamella is usually not visible, obscured by antennal scapes; clypeus projecting relatively less beyond mandibles compared to JTL-004.

Notes

For general observations on biology of genus, see horni.

In Costa Rica, I have collected workers of this species from three different Winkler samples from three different sites on and near the Osa Peninsula: Sirena, Rancho Quemado, and a site 19km S of Ciudad Neilly.

There is a complex of species around humilis. In Costa Rica there are two species: humilis s.s. and JTL-004. In P. S. Ward's collection at UC Davis I observed specimens from Colombia and Venezuela that matched Costa Rican and Panamanian humilis, although they were quite variable in size. There was also material from the Dominican Republic that had a similar clypeal structure but had a punctate face. There was a collection from Ecuador that was like a large version of JTL-004, with punctate face and large, subtriangular clypeal projection.

Type data

Discothyrea humilis Weber 1939:100. Two syntype dealate queens: Panama, Barro Colorado Island (Weber). "One female was found among decayed leaves and humus on a fallen log, the other in debris swept down by a swollen stream from the forest." [MCZC] (one syntype queen examined). Measurements: HW 0.347, HL 0.379.

Discothyrea icta Weber 1939:101. Two syntype dealate queens: "two dealate females taken by myself under leaves at the base of a saman tree (Pithecolobium saman) on the grounds of the Imperial College of Tropical Agriculture, St. Augustine, Trinidad, B.W.I., August 3, 1935." [MCZC] (examined). PROPOSED NEW SYNONYMY. Measurements: HW 0.364, HL 0.406.

I have examined the types of humilis and icta side by side, and can find no substantial difference.

Literature Cited

Weber, N. A. 1939. New ants of rare genera and a new genus of Ponerine ants. Ann. Entomol. Soc. Am. 32:91-104.


Page author:

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


Date of this version: 18 February 1999
Previous versions of this page: 3 January 1999
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