Formicidae, Hymenoptera, Insecta, Arthropoda, Animalia
Range
Mexico to tropical South America (Lattke 1995). Costa Rica: La Selva and Osa Peninsula.
Identification
Promesonotal suture absent; scapes surpass margin of vertex when laid back; mandibles smoothly curving such that basal and apical margins form a continuous convexity; head in back of antennal insertions black or nearly so; mandibles straw yellow, contrasting sharply with black of cranium; mesosoma, node and gaster varying from black to yellowish-red; costulae of posterior face of propodeum longitudinal; eyes relatively large and elongate (eye length = 0.36, width = 0.23, n=2 workers).
Natural History
This species inhabits lowland rainforest, and is known from isolated workers, usually encountered in fresh treefalls.
Selected Costa Rican records:
Heredia: La Selva Biological Station, 10¡26'N, 84¡01'W, 50m (J. Longino). Collecting in recently cleared plot; trees being felled during collecting; medium to large trees over abandoned cacao; old second growth. Worker on vegetation.
Limon: Hitoy Cerere Biological Reserve, 9¡40'N, 83¡02'W, 100m (J. Longino). Primary forest and second growth habitats; diurnal strays.
Puntarenas: Sirena, Corcovado National Park, 8¡29'N, 83¡36'W, 5m (J. Longino). Lowland rainforest; worker in recently fallen Basiloxylon tree.
Puntarenas: San Pedrillo, Corcovado National Park, 8¡37'N, 83¡44'W, 5m (J. Longino).
Taxonomic Notes
Brown (1958) treated sulcata and tornata as distinct, based on the same characters used here, but speculated that they could turn out to be variants of one plastic species. Lattke (1995) supported the latter position, treating sulcata and tornata as synonyms because over the full range of the complex there are intermediate forms. For example, he stated "Color is of no help in separating the ... forms, except at an occasional local level" (italics mine). Color and other characters separate the two forms at the local level in Costa Rica, where they appear to be distinct and broadly sympatric. I feel that species have their greatest objectivity at the local level, and follow Gentry (1990) in giving locally defined species primacy.
Type data
Ectatomma sulcatum F. Smith 1858:99. Syntype worker: Brasil, Amazonas: Ega (=Tefe).
Literature Cited
Brown, W. L., Jr. 1958. Contributions toward a reclassification of the Formicidae. II. Tribe Ectatommini (Hymenoptera). Bulletin of the Museum of Comparative Zoology 118:175-362.
Gentry, A. H. 1990. Herbarium taxonomy versus field knowledge; is there an attainable solution? Flora Malesiana Bulletin Special Volume 1:31-35.
Lattke, J. E. 1995. Revision of the ant genus Gnamptogenys in the New World (Hymenoptera: Formicidae). Journal of Hymenoptera Research 4:137-193.
Smith, F. 1858. Catalogue of hymenopterous insects in the British Museum. VI. Formicidae. 216pp., 14 pls.
John T. Longino, The Evergreen State College, Olympia WA 98505 USA.longinoj@evergreen.edu