Page:Memoirs on the coleoptera (IA memoirsoncoleopt01case).pdf/17

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Staphylinidæ.
9

punctures rather well separated even on the elytra, the abdomen polished, minutely, sparsely punctuate; blackish-piceous, the pronotum a little paler, the elytra still paler; legs and basal joint of the antennæ very pale; head well developed, the eyes convex, prominent, at nearly their own length from the base, the tempora arcuate and converging behind them, the carinæ distinct, entire; antennæ moderately long, rather rapidly and strongly incrassate distally, the second joint cylindric, the third obconic and a little longer, both very elongate, the outer joints distinctly transverse; prothorax relatively small, strongly transverse, parallel and strongly rounded at the sides, much wider than the head and correspondingly much narrower than the elytra, which are parallel, rather strongly transverse and much longer as well as wide then the prothorax; abdomen parallel, slightly narrower than the elytra, the fifth tergite slightly longer than the fourth; mesosternum extending beyond the middle of the coxæ, very wide between them and flat, with the apex broad and circularly rounded, approaching the apex of the larger triangular metatarsal projection by its own apical width, the angle of the metasternum rounded; hind tarsi slender, the four basal joints equal. Length 2.7 mm.; width 0.75 mm. Virginia (Fort Monroe).

Though represented only by the female, this species is so distinct in its structural characters that it could not be mistaken; the male characters would probably decide whether it is to be properly associated with the other species of the subgenus or not; it is certainly remarkably different from them in general appearance and all characters except the very broad sterna.


Macroterma Csy.

This subgenus of Atheta is related to Stethusa and has the same very broad and apically arcuate process of the mesosternum, but it is here shorter and separated from the metasternum by a longer interval. The eyes are much smaller, being at nearly their own length from the base of the more parallel-sided head, the outer antennal joints much shorter and more transverse, with the last greatly elongate, being almost as long as the three preceding combined; the male sexual characters are materially different and more complex. Of the three described species, borealis Csy., is unfortunately founded upon the female, but it may be distinguished from alutacea Csy., by the more sparsely punctulate and puberulent and more polished integuments; dentata Bernh., has the head and prothorax relatively smaller and more transverse, with the protuberance of the fifth male tergite very much smaller and of different form. The following is another species: