Page:Memoirs on the coleoptera (IA memoirsoncoleopt01case).pdf/13

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Staphylinidæ.
5

wide, the mesosternal process only extending to slightly beyond the middle of the coxæ, with its apex transversely to circularly rounded and separated from the angular apex of the metasternal projection by a short and slightly depressed interval. This section of Atheta includes numerous species in North America, the following being some of the many allies of klimschi:

Atheta (Stethusa) affluens n. sp.—Stout, parallel, moderately convex, blackish-piceous, the elytra and legs pale, the former obscure flavate, the abdomen black, scarcely paler apically; anterior parts moderately shining, minutely, closely punctuate and finely, closely, and inconspicuously pubescent; head four-fifths as wide as the prothorax, transversely orbicular, the eyes large; antennæ fuscous, pale at base, extending to the middle of the elytra, gradually moderately enlarged distally, the third joint slightly longer than the second, both elongate, the tenth slightly wider than long, the eleventh as long as the two preceding; prothorax two-fifths wider than long, nearly as wide as the elytra, parallel, the sides broadly arcuate, the median line very finely, almost imperceptibly impressed throughout; elytra a little wider and longer than the prothorax; abdomen more shining and more sparsely punctulate, a little narrower than the elytra, subparallel, the fifth tergite (♂) transversely truncate, unmodified, the sixth strongly arcuate at tip and acutely dentate at each side, the middle of the arc narrowly truncate, the truncature marked at each end by a very small convex knob and the surface adjoining feebly impressed. Length 2.7 mm.; width 0.7 mm. Rhode Island (Boston Neck) and New York (Long Island).

Specimens not clearly separable from the considerable type series are before me from New Jersey (Anglesea), North Carolina (Asheville), Mississippi (Pass Christian) and Arkansas (Little Rock). It is a widely diffused species, readily distinguishable by its large convex eyes, extending almost to the base of the head, by the medial truncature of the sixth male ventral scarcely so wide as the distance separating it from the lateral slender teeth and not extending behind the latter, and by the sternal characters.

Atheta (Stethusa) irvingi n. sp.—Form, coloration and sculpture nearly as in affluens, the head relatively larger but otherwise similar, fully five-sixths as wide as the prothroax, the latter even relatively larger than in affluens, similar, except that the parallel sides are slightly less rounded; antennæ with the last joint evidently shorter; elytra similar, but little wider than the prothorax and with the humeri only very narrowly exposed at base: abdomen less parallel, slightly narrowing near the apex, the fifth tergite (♂) similarly truncate and unmodified, the sixth with the apical arcuation larger, with smaller lateral teeth, the median truncature sinuate, with the adjacent surface more impressed and its ends not marked by swollen joints. Length 2.5 mm.; width 0.65 mm. New York (Catskill Mts.).