Platythyrea

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 : 57-58

Platythyrea Roger

Worker.-Small or medium-sized, slender, monomorphic, opaque black ants, with pruinose surface and very poorly developed pilosity, with flat clypeus often without a posterior suture, indistinct frontal area and large, thick, expanded and widely separated frontal carinae. Mandibles large, triangular, with edentate or finely denticulate apical border. Maxillary palpi 6-jointed, labial palpi 4-jointed. Antennae stout, funiculi without a distinct club. Eyes rather large; ocelli absent. Premesonotal suture distinct, other thoracic sutures feeble or obsolete. Petiole massive, not squamiform, its posterior articulation at the middle of the anterior surface of the petiole. The constriction between the latter and the gaster moderately pronounced. Middle and hind tibiae with two spurs; claws with a single tooth.

Female winged, very similar to the worker and but little larger; eyes larger, but ocelli not always developed. Pronotum large; mesonotum depressed. Wings with two closed cubital cells, a discoidal cell and a closed radial cell as in many other Ponerinae.

Male more like the female than in most genera of the subfamily; clypeus more convex than in the worker and female; frontal carinae not dilated anteriorly. Mandibles triangular, with sharp apical border. Antennae 13-jointed; scape a little shorter than the second funicular joint. Eyes and ocelli very large. Pronotum large, not overarched by the mesonotum, the latter convex, with indistinct Mayrian furrows. Petiole much as in the worker. Pygidium rounded; cerci developed.

This genus, of which more than 35 species arc; known, ranges oven the tropics of both hemispheres (Map 7) and is represented by more species in Africa and Madagascar than in the Indoaustralian or Neotropical Regions. Our American and many of the African species seem to feed largely or exclusively on termites. I have found P. punctata (Smith) of the West Indies nesting in termitaria. Arnold gives some notes on the habits of two of the African forms. Of P. lamellosa (Roger) subsp. longinoda, Forel variety rhodesiana Forel he says:

The nest of this species is go distinctive that it cannot be mistaken for that of any other Ponerinae. The entrance is surmounted by a dome, from 6 to 8 inches high, by about 12 inches broad at the base. The dome is built up of very even-sized small pebbles, about 5 to 8 mm. in their largest diameter. The entrance is situated in the center above, and this is generally the only entrance, very exceptionally there may be a smaller and less regular opening at the base of the mound.

He gives the following account of P. arnoldi Forel : I have met with this species on only one occasion. The nest, situated on an open piece of ground, was surmounted by a mound with the entrance at the apex, as in lamellosa variety rhodesiana , but unlike that species the mound of arnoldi contains' large pebbles, The surface of the mound was covered with the elytra and carcasses hundreds of beetles, mostly Tenebrionidae. Workers were seen carrying live [[...]] to the nest, the prey being held by its mandibles in a position above and part of the body of the ant. Since a careful examination of the rubbish-heap of [[...]] failed to show the remains of other insects, it is probable that this species feeds entirely on Coleoptera, differing in this respect from most of the other members of the genus, which in Rhodesia, at any rate, are entirely termitophagous.