Ocymyrmex celer Weber, 1981

Bolton, B., 1981, A revision of six minor genera of Myrmicinae (Hymenoptera: Formicidae) in the Ethiopian zoogeographical region., Bulletin of the British Museum (Natural History) Entomology 43, pp. 245-307 : 267

Ocymyrmex celer Weber stat. n.

(Fig. 19)

Ocymyrmex weitzeckeri subsp. celer Weber , 1943: 368. Syntype workers, Sudan: Torit, N. of Imatong Mts, 6. viii. 1939, no. 1462 (N. A. Weber) (MCZ, Cambridge) [examined].

Worker: TL 8.1 - 8.5, HL 1.98 - 204, HW 1.82 - 1.88, CI 91 - 94, SL 1.68 - 1.73, SI 89 - 95, PW 1.12 - 1.16, AL 2.30 - 2.46 (4 measured).

Anterior clypeal margin with a conspicuous median impression which is flanked on each side by a low broad tooth. Sides of head in front of eyes more or less parallel in full-face view, not obviously diverging anteriorly as is frequent in the genus. Maximum diameter of eye 0.38 - 0.39, about 0.21 x HW. Dorsum of pronotum in profile flat to indented, sloping upwards behind to its junction with the mesonotum; the promesonotum not forming a single even convexity. Dorsum of propodeum rounding broadly and evenly into the sloping declivity. Metapleural lobes deep but narrow, rounded and little projecting. Petiole node in profile small, low and rounded, in dorsal view longer than broad. Postpetiole in dorsal view slightly longer than broad. First gastral tergite with a neck-like constriction basally. Dorsum of head finely densely and regularly longitudinally costulate, the costulae low and superficial, weakly developed, parallel and arching outwards behind the eyes. Spaces between the costulae highly polished, without strong granular or punctulate ground-sculpture; the whole head with a slick and glossy appearance. Pronotum with weak to feeble arched-transverse costulate sculpture dorsally, which may be almost effaced centrally, the space between the mesothoracic spiracles with longitudinal or transverse costulate sculpture. Remainder of dorsal alitrunk transversely and more strongly costulate. Sides of alitrunk regularly densely sharply costulate everywhere. Petiole node with transverse rugulae ventrally which may extend for some distance up the sides, and with faint rugulae on the dorsal peduncle, but the dorsum of the node unsculptured or only with the faintest vestiges present. Postpetiole only with superficial patterning. All dorsal surfaces of head and alitrunk with numerous hairs of varying length; first gastral tergite with hairs shorter and much sparser than on alitrunk. Colour glossy dull red, the gaster dark brown.

Along with nitidulus this species can be separated from all others in which the clypeus is impressed and the first gastral segment constricted by the slick and glossy appearance of the head. In all others the ground-sculpture on the head consists of quite conspicuous granulation or punctulation, but in celer and nitidulus this is very reduced or absent, leaving the spaces between costulae smooth or very nearly so, and shining. The two may be distinguished by the shape of the pronotum, which in nitidulus is convex and, together with the mesonotum, forms an evenly convex surface. In celer the pronotum is flat and an even convexity does not result, compare Figs 18 and 19.

Material examined Sudan: Torit (N .. A. Weber).