Pseudolasius bucculentus Wheeler, 1922, new species

Pseudolasius bucculentus, new species

Text Figure 56

Worker major.- Length 3.2 mm.

Head large, as broad as long, broader behind than in front, with convexly inflated sides and front and deeply and angularly excised posterior border, the posterior corners being somewhat conical. Mandibles apparently 5-toothed, folded under the clypeus, which is short and in the middle convex and obtusely carinate; its anterior border in the middle with a shallow excision. Eyes very small and indistinct, situated a little in front of the median transverse diameter of the head. Frontal groove rather distinct; frontal carinae very short; frontal area transverse, triangular, not impressed. Antennae rather slender, the scapes not reaching to the posterior corners of the head; first funicular joint as long as the two succeeding joints together; joints 2 to 7 of subequal length, all slightly longer than broad. Thorax robust, pronotum broad, in profile only feebly convex above, the mesonotum rising higher than the pronotum to its middle and then sloping and concave to the mesoepinotal suture. Epinotum with distinct base and declivity, the former short, sloping upward but not reaching the height of the mesonotum, the declivity flat and gradually sloping backward, more than twice as long as the base. Petiole small, with sharp, compressed, very distinctly notched superior border. Gaster voluminous, subelliptical, its anterior segment flattened in front and overlying the petiole. Legs long and stout.

Whole body, including the mandibles, shining and very finely and uniformly punctate, except the mandibles, which are longitudinally striate.

Pilosity and pubescence yellow, the former short, very sparse, absent except about the mouth and on the thoracic dorsum and as a single row of hairs along the posterior border of each gastric segment. Pubescence short and delicate but very dense, more conspicuous on the head and gaster than on the thorax, very fine and short on the appendages, the latter without erect hairs as in bufonum.

Uniformly brownish yellow; mandibular teeth and eyes blackish.

Worker minor.- Length 2.2 to 2.5 mm.

Differing from the major in the shape of the head, which is distinctly longer than broad, as broad in front as behind, with less convex, subparallel sides and less deeply excised posterior border. Eyes extremely small, reduced to one or two ommatidia, pigmentless. Scapes extending a short distance beyond the posterior corners of the head. In other respects like the major worker.

Male.- Length 3 mm.

Closely resembling the male of bufonum but with the head broader than long and especially broader and more swollen behind. Body and wings much paler, brownish yellow, the posterior portion of the head dark brown. Wings opaque, grayish, with pale brown veins and pterostigma. The pilosity is also very different, the hairs being very few and confined to the mouth-parts and genital appendages.

Described from a single major worker, two minor workers, and a male taken at Medje (Lang and Chapin). without further data. This species is quite distinct in the peculiar shape of the head and mesonotum of the worker major, the strongly notched petiolar border and the very feebly developed pilosity.