Omalium Gravenhorst. Man. N.Z. Coleopt., p. 115
54. Omalium robustum sp. nov.
Robust, elongate, subdepressed; hind-body with distinct slender greyish setae, thorax and elytra glabrous; nigrescent, subopaque, the front of the head and parts of thorax shining, legs and antennae variable, generally pale castaneous, the terminal half of these latter darker.
Head evidently smaller than thorax, logitudinally bi-impressed, nearly smooth and shining along the middle, but dull with dense minute sculpture behind, its punctation fine and irregular: the ocelli situated in small foveae in line with the back part of the eyes, these are large and moderately prominent. Thorax rather broader than long, its sides finely margined, nearly straight, just a little curvedly narrowed in front, apex subtruncate, with obtuse angles, the base straight, with almost rectangular angles; disc with a pair of large impressions which are somewhat expanded behind, their outer borders and the narrow space between them shining but not perfectly smooth; nearly all the rest of the surface is rendered dull by the dense minute sculpture; the punctures are irregularly distributed, distant on the glossy parts and apparently nearly absent at the sides. Scutellum triangular. Elytra oblong, double the length of thorax; shoulders slightly prominent and clasping the thoracic angles; apices truncate, but oblique near the sides; with fine subseriate punctures visible along the dull dense sculpture of the surface. Hind-body gradually narrowed posteriorly, closely and finely punctured, the basal 3 segments about equal and broadly marginated, 4th slightly longer, 5th subconical, the basal with a pair of rotundate pale specks.
Antennae as long as the head and thorax; their basal joint long and stout; 2nd short; 3rd elongate, nearly as long as the 4th and 5th combined; joints 6–11 loosely articulated, finely pubescent, broader than the preceding
ones; 9th and 10th transverse. Tibiae with numerous slender yellow spines along the outer edge. Tarsi, the anterior particularly, with very elongate pale hairs underneath, their 5th joint longer than all the others taken together.
Underside subopaque, nigro-fuscous, trochanters reddish; finely punctate, the intervals minutely sculptured, with distinct greyish-yellow pubescence.
Var.—Body castaneous, head nigrescent, antennae and legs testaceous. Evidently rare.
The abnormal bulk and peculiar sculpture are its distinctive features.
Length, 4–4 ½ mm.; breadth, 1 ½ mm.
Found by Mr. T. Hall. Probably common.