Discothyrea denticulata, Weber, N. A., 1939

Weber, N. A., 1939, New ants of rare genera and a new genus of ponerine ants., Annals of the Entomological Society of America 32, pp. 91-104 : 100-101

Discothyrea denticulata , sp. nov. (Fig. 4)

Worker.-Length, 1.0 mm. Head, excluding mandibles, one-tenth longer than wide; in front view sub-circular in outline with occipital margin transverse in middle; antennae 7-jointed, scapes inserted closely together and separated only by a vertical plate which in side view appears as a forwardly directed rectangular plate bearing an acute tooth in front. Eyes small, situated much closer to mandibular insertions than to occipital angles. Mandibles triangular, edentate. Antennal scapes clavate; funiculi with terminal joint ovate and distinctly longer than remainder of joints taken together. Thorax from above widest in pronotal region with sides converging posteriorly to epinotum. Epinotal spiracles projecting as tubercles; declivous surface of epinotum slightly concave and bordered by feeble, rounded carinae. Petiole from above transversely rectangular with rounded corners. 1st gastric segment from above truncate anteriorly, with rounded corners. Legs of moderate proportions.

Entire surface, including gaster and appendages, dull, finely punctate. Entire surface covered with a microscopically fine and appressed pupescence, without erect hairs.

Color uniformly light brown. Described from one worker taken by myself in virgin greenheart(Nectandra Rodei Schomb.) forest near the Forest Settlement, Mazaruni River, British Guiana, Aug. 23, 1935. The ant was among leaves on the forest floor.4

This species differs from D. horni Menozzi from Costa Rica and D. testacea Roger from "North America" (genotype) in possessing seven instead of nine antennal joints. From the female of D. neotropica Bruch of the Argentine this species differs in proportions of antennal joints and in having the plate between the antennal scape bases toothed. Of neotropica (known only from the type female) Dr. Bruch writes (Bruch, 1919) "Respecto al número reducido de los artejos antenales en D. neotropica (9 en el genotipo), he creído bien consultar al Dr. Santschi de Kairouan. Mi distinguido colega me aconsejó conservar el nombre generico, y opina que la contracción de estos artejos es tal vez instable, habiéndola observado con Discothyrea Traegaordhi Sants., y en una preparación en bálsamo de Canadá, donde no constan sino 6 artejos, los otros todos más o menos soldados e indefinibles." I am therefore leaving this species in the genus Discothyrea . The possibility that the genotype, testacea, described in 1863 presumably from "North America" and not recorded since, may also show variability in antennal joint number must be entertained. That it cannot be this species is indicated by the size of testacea (1.5 mm. for worker, 2 mm. for female), among other differences.