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

by Thomas Lincoln Casey

Micratheta n. subgen.

In this subgenus the body is minute in size and of peculiar parallel convex form, the mesosternal process extending but slightly behind the middle of the coxæ, with its apical part subparallel but rather wide, the apex subacutely rounded and rather closely approaching the long and acute metasternal projection, the intervening narrow ridge not or scarcely depressed and the coxæ well separated. The tarsi seem to be rather long but the posterior are missing in my only example. The hypomera appear to be fully visible from a lateral viewpoint but are rather more inflexed than in Atheta.

Atheta (Micratheta) caudex n. sp.—Parallel, convex, strongly shining, the reticulation wholly wanting on the head and pronotum but coarse, though not strong, on the elytra and abdomen, becoming transversely wavy on the latter posteriorly, the punctures fine but rather strong, not asperate; color deep black, the elytra piceous, the legs pale; pubescence very inconspicuous; head nearly as long as wide, gradually broadening to the base, the eyes rather small, anterior and not at all prominent, the carinæ very fine but almost entire; antennæ short, gradually and moderately stout and incrassate distally, compact, the outer joints transverse, the last obtuse, not quite as long as the two preceding, the second moderately long, almost as long as the next two combined, the third but little longer than wide; prothorax moderately transverse, large and convex, parallel, the sides very feebly and evenly arcuate from apex to base, distinctly wider than the head and fully as wide as the elytra, unimpressed; elytra short, transverse, the suture apparently very slightly shorter than the prothorax, the apices very broadly and feebly sinuate laterally; abdomen parallel, with feebly arcuate sides, fully as wide as the elytra, finely, not densely punctate, the fifth tergite rather shorter than the fourth. Length 1.42 mm.; width 0.4 mm. Virginia (Fort Monroe).

The type and only known specimen of this isolated species flew upon my newspaper while on a steamer in Hampton Roads.