Comprehensive DescriptionRead full entry
Leptogenys HNS Roger
Slender black or reddish ants, of small or medium size, sometimes with bluish iridescence.
The workers are monomorphic and vary little in size. Mandibles articulated at the anterior corners of the head, almost or quite toothless and either long and linear or broader and subtriangular, usually with the angle between the basal and apical margin rounded or absent. Clypeus usually carinate. and projecting in the middle in the form of a lobe or angle. Antennae long and slender, the funiculi not enlarged or clubbed apically. Thorax usually with the mesoepinotal suture distinct. Petiole either laterally or, in a few species, anteroposteriorly compressed. Abdomen small and slender, the constriction between the postpetiole and gaster not very pronounced. Legs slender, claws pectinated.
The female is wingless and scarcely larger than the worker, either highly ergatomorphic, without ocelli, with the thoracic structure as in the worker but with more voluminous abdomen, or ergatogynous, as in the case of L. ergatogyna HNS described below, with ocelli and the thorax more like that of the winged females of other genera, but with the mesonotum and scutellum small and depressed.
The male is somewhat smaller than the worker and in some species much paler in color and nocturnal, with very large eyes and ocelli, very long antennae, small mandibles, and pronounced Mayrian furrows on the mesonotum. The claws are pectinated as in the other phases.
Emery has divided the genus into four subgenera: Leptogenys HNS sensu stricto; Lobopelta HNS .; Odontopelta; and Machaerogenys. The species of Leptogenys HNS , sensu stricto, are generally distributed in the tropics of both hemispheres. One Lobopelta HNS , L. elongata (Buckley) HNS , occurs in the Gulf States from Central Texas eastward to Florida. Odontopelta is monotypic and confined to Queensland. Of Machaerogenys, three species are known, all from Madagascar (Map 15).
Most species of Leptogenys HNS form small colonies, each with a single female, and nest in the ground, usually under stones or logs. The workers are timid and extremely quick in their movements. Some species make organized raids on termites; others, like our North American elongata HNS , forage singly and apparently only at night.