Rhoptromyrmex

Wheeler, W. M., 1922, The ants collected by the American Museum Congo Expedition., Bulletin of the American Museum of Natural History 45, pp. 39-269 : 194-195

Rhoptromyrmex Mayr

Worker small, allied to Tetramorium . Antennae 12-jointed, with 3-jointed club, as long as or slightly longer than the remainder of the funiculus. Maxillary palpi 3- jointed; labial palpi 2-jointed. Head broader behind than in front, with convex sides and small, moderately convex eyes at the middle of its transverse diameter. Ocelli absent. Clypeus flattened or moderately convex, ecarinate, its anterior border entire, a little produced, narrowed on the sides and bluntly ridged in front of the small antennal foveae. Frontal carinae short and more or less diverging; frontal area large but not impressed. Scrobes absent. Thorax short and stout, convex and rounded above, with feeble or obsolete promesonotal suture, somewhat constricted or impressed at the mesoepinotal suture, the epinotum unarmed. Petiole pedunculate, the node rounded, narrower than. the postpetiole, which is transversely elliptical and rounded above. Gaster oval, formed very largely by the first segment. Legs moderately long, femora not incrassate in the middle, the middle and hind tibia; with or without short simple spurs.

Female somewhat larger than the worker, with 12-jointed antennae but differing considerably in structural details in the various species. Fore wings with a cubital, a discoidal and an open radial cell.

Male with 10-jointed antennae and elongate second funicular joint, as in Tetramorium , and closely resembling the males of this genus also in other respects. Wings as in the female.

The species of this genus are confined to the Ethiopian Region (Map 28). A few Indian forms formerly referred to the genus have been recently placed by Emery in a new genus, Acidomyrmex , characterized by having very long, straight and diverging epinotal spines.