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

by Thomas Lincoln Casey

Donesia n. subgen.

This name is proposed for a small species, at first sight resembling the preceding but distinguishable by the form of the head and the complete absence of all trace of infra-lateral carinæ; the type is the following:

Atheta (Donesia) temporalis n. sp.—Nearly parallel, rather depressed, subalutaceous, very finely and distinctly micro-reticulate throughout, more feebly on the abdomen, the punctures extremely fine, close but wholly inconspicuous; color piceous-black, the elytra and legs but slightly paler, piceous; head rather well developed and transverse, the eyes somewhat small, strongly convex, at a little more than their own length from the base, the parallel tempora broadly arcuate and sensibly more prominent than the eyes; antennæ not very stout, very gradually and feebly incrassate, piceous throughout, extending to about the middle of the elytra, the second joint cylindric, about as long as the more obconic third, tenth slightly wider than long, the eleventh as long as the two preceding; prothorax transverse, almost as wide as the elytra but much wider than the head, the parallel sides feebly arcuate, straighter basally, the angles obtuse though rather distinct, the median line very faintly impressed; elytra very moderately transverse, much longer than the prothorax; abdomen narrower than the elytra, parallel basally, thence very feebly narrowed to the apex, the fifth tergite much longer than the fourth, the sixth in the type notably narrow, the apex feebly and gradually sinuate in about the median third; mesosternal process extending only slightly behind the middle of the coxæ, the apex gradually prolonged and very finely aciculate, separated from the extremely short and broadly, very obtusely subangulate metasternum by a rather long sunken interval, which is rather sharply ridged; hind tarsi with the basal joint shorter than the second. Length 2.0 mm.; width 0.43 mm. Rhode Island (Boston Neck).

The rather depressed form, very fine sculpture and swollen tempora, which however are not at all as in Amischa, will render the identification of this species comparatively easy. The abdomen differs from anything in the preceding subgenus in being evenly though not densely asperulato-punctulate throughout, and the sixth ventral segment is much narrower.