Memoirs on the Coleoptera/Volume 1/New Species of the Staphylinid Tribe Myrmedoniini/Tribe Myrmidoniini/Group Athetæ/Atheta/Megista

by Thomas Lincoln Casey

Megista Rey.

The following species agrees very well with subplana in all its structural characters, including nearly obsolete infra-lateral carinæ of the head, short basal joint of the hind tarsi and approximate middle coxæ, with very short metasternal projection, but the mesosternal process is noticeably longer. Granulata Mann., (Elytrusa Csy.) is closely allied but larger and with a notably larger head and still longer and stouter antennæ; I do not think that granulata can be the same as the European graminicola Grav.

Atheta (Megista) nomadica n. sp.—Moderately stout, parallel, deep black, moderately convex, rather strongly shining, the elytra not distinctly picescent, the antennæ nearly black, the legs piceous-brown; head small, orbicular, the eyes at more than their own length from the base; antennæ long, very moderately incrassate, the tenth joint obtrapezoidal, about as long as wide, the eleventh pointed, almost as long as the two preceding; prothorax distinctly narrower than the elytra and very much wider than the head, relatively larger than in subplana, moderately transverse, parallel and rounded at the sides, very minutely, not closely punctulate and with a rather large but feeble transverse ante-basal impression; elytra large, wider than long, very much longer than the prothorax, the punctures moderately close-set and distinctly but not coarsely graniform, less strongly than in granulata; abdomen parallel, narrower than the elytra, minutely rather sparsely punctulate, much more distinctly and less sparsely than in granulata, where the abdomen is almost sculptureless. Length 3.2 mm.; width 0.78 mm. Alaska (Nome).

Related to granulata but differing in its smaller head, more rounded sides of the prothorax, more punctulate abdomen and smaller size.