Pseudolasius bufonum, Wheeler, W. M., 1922

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: 219-221

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Pseudolasius bufonum

new species

Pseudolasius bufonum   HNS   , new species

Text Figure 55

Worker major.- Length 2.8 to 3 mm.

Head scarcely longer than broad, subrectangular, with nearly straight, subparallel sides and sinuately excised posterior border. Mandibles 5-toothed, the median tooth small, the apical long and pointed, the others shorter and subequal. Clypeus convex. Subcarinata in the middle, its anterior border entire, only slightly projecting over the bases of the mandibles. Eyes very small, consisting of only three or four ommatidia, situated a little in front of the median transverse diameter of the head. Antennal scapes not reaching to the posterior corners of the head; first funicular joint longer than the two succeeding joints together; second joint as broad as long, joints 3 to 7 slightly longer than broad. Thorax short, stout; pronotum large and broad, longer than the mesonotum, which is as long as broad; epinotum broader than long. In profile the pro- and mesonotum form a large convexity with rather uneven outline, interrupted by the strong premesonotal suture. Mesoepinotal impression short and not very deep, the stigmata prominent. Epinotum decidedly lower than the mesonotum, in profile rounded and sloping, with very short base and long sloping declivity. Petiole, small, rather strongly compressed antero-posteriorly, with entire superior border. Gaster elongate elliptical. Legs rather stout.

Mandibles opaque, very finely and longitudinally striated. Remainder of body shining, very finely and rather densely punctate, but not more coarsely on the head and thorax than on the gaster. Clypeus smoother and more shining than the remainder of the head.

Hairs and pubescence yellowish, abundant; the former erect, longest on the thoracic dorsum, sparser and shorter on the scapes and legs; pubescence rather long and dense over the whole body but only slightly obscuring the shining surface.

Yellowish brown; gaster and appendages paler and more yellow; mandibles castaneous, their teeth and a blotch on the vertex blackish.

Worker minor.- length 2.5 to 3 mm.

Differing from the major worker in the shape of the head, which is decidedly smaller, distinctly longer than broad, with straight sides and only feebly excised posterior border. Eyes reduced to a single ommatidium or absent. Antennal scapes reaching to the posterior corners of the head; first funicular joint broader than long, joints 3 to 7 not longer than broad.

Sculpture, pilosity, and color as in the major worker, but the black spot on the vertex fainter or altogether absent.

Female.- Length 5.5 to 6 mm.

Head, excluding the mandibles, broader than long, slightly broader behind than in front, with feebly convex sides and broadly and feebly excised posterior border. Eyes slightly convex, very broadly elliptical, occupying the median third of the sides of the head. Antennal scapes extending nearly one-third their length beyond the posterior corners of the head; all the funicular joints longer than broad. Thorax broader than the head; the mesonotum and scutellum flattened. Apical border of petiole blunt, straight, and transverse. Gaster large, elliptical. Wings long.

Sculpture, pilosity, and color much as in the worker, but the body darker brown, the gaster not paler than the thorax. Anterior border of clypeus blackish. Hairs lacking (possibly rubbed off), pubescence shorter and more delicate, and the surface, especially of the head and thorax, somewhat more opaque than in the worker. Wings blackish, with dark brown veins and pterostigma.

Male.- Length 2.5 mm.

Head as broad as long, somewhat narrowed behind and in front. Eyes convex, hemispherical, somewhat in front of the middle of the sides, the posterior border nearly straight. Mandibles denticulate, overlapping. Clypeus convex. Antennal scapes extending about one-fourth their length beyond the posterior border of the head; all the funicular joints distinctly longer than broad, the first nearly as long as the two succeeding joints together. Thorax and petiole shaped somewhat as in the female. Gaster and legs slender, external genital valves rather long and pointed.

Sculpture and pilosity much as in the worker. Color yellowish brown above, with brownish yellow appendages, genitalia, venter, and anterior portion of head. Ocellar triangle dark brown. Wings paler than in the female.

Described from four major and eleven minor workers, three females, and eight males, all taken from the stomachs of toads (Bufo superciliaris and polycercus) captured at Medje (Lang and Chapin).

This species differs from weissi   HNS   in the shape of the head of the major worker, the slightly larger eyes, more strongly striated and more opaque mandibles, shorter antennae, and much more abundant pilosity and pubescence, and especially in having erect hairs on the scapes and legs. The female is smaller than that of weissi   HNS   , with a differently shaped head, less excised behind, larger and more nearly circular eyes and longer antennae.