Formicidae, Hymenoptera, Insecta, Arthropoda, Animalia
Identification (the genus has been revised by Andrade 1998)
Worker and queen: mandible with elongate puncta and linear etchings, interspaces smooth; in full-face view frontal carinae just barely project beyond anterior border of clypeus; median prominence formed by anterior borders of frontal carinae evenly rounded, not notched medially; metatarsus (basal tarsal segment) of middle leg subequal in length to following two segments, with row of 5 peg-like setae on outer distal margin; AT2-AT4 finely longitudinally striate, striae becoming finer from AT2 to AT4, weak striae extending onto AT5.
Male (based on Andrade's study of males from southern Brazil): frontal carinae not strongly converging posteriorly; if almost touching each other posteriorly then never broadly separated anteriorly; head and basal face of propodeum with thin striae; hypopygium with a simple median projection between the apodemes.
Range
Costa Rica, Venezuela, Ecuador, Peru, Brazil.
Natural History
The ants of this genus are rarely collected, and very little is known about them. Cylindromyrmex species nest in cavities in sound or rotten wood, under bark, in hollow stems, or in termite galleries (Brown 1975).
Costa Rican Specimen Records
Heredia: La Selva Biological Station, 10ˇ26'N, 84ˇ01'W, 50m, lowland rainforest, 1993 (coll. ALAS), alate queen in malaise trap.
Type data
Cylindromyrmex brevitarsus Santschi 1925:5. Syntype worker: Brazil, Parana: Rio Negro (Reichensperger) [NHMB].
Notes
Andrade (1998) discussed the similarity of brevitarsus from South America and darlingtoni from Cuba. The diagnostic differences were that in brevitarsus (1) the frontal carinae reached but did not surpass the anterior clypeal border, (2) the mandibles had 6-8 denticles instead of 9-10, and (3) the ventral surface of the hind coxae were strongly striate instead of weakly striate. The single Costa Rican queen I have examined has the frontal carinae just barely surpassing the clypeal border, the mandibles with about 8 denticles (although I find these difficult to count), and the ventral surface of the coxae distinctly striate. Thus the bounds between these two species seem somewhat blurred. I choose to refer to this specimen as brevitarsus, the older name.
Andrade (2001) examined the La Selva specimen mentioned above and identified it as brevitarsus, also commenting on the close relationship to the Cuban darlingtoni.
Literature Cited
Andrade, M. L. de 1998. Fossil and extant species of Cylindromyrmex (Hymenoptera: Formicidae). Revue Suisse de Zoologie 105:581-664.
Andrade, M. L. de 2001. A remarkable Dominican amber species of Cylindromyrmex with Brazilian affinities and additions to the generic revision (Hymenoptera: Formicidae). BeitrŠge zur Entomologie 51:51-63.
Brown, W. L., Jr. 1975. Contributions toward a reclassification of the Formicidae. V. Ponerinae, tribes Platythyreini, Cerapachyini, Cylindromyrmecini, Acanthostichini, and Aenictogitini. Search Agri., Entomol. (Ithaca) 5:1-115.
Santschi, F. 1925(1924). Nouvelles Fourmis Bresiliennes. Annls Soc. Entomol. Belg. 64:5-20.
Page author:
John T. Longino, The Evergreen State College, Olympia WA 98505 USA. longinoj@evergreen.edu