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

by Thomas Lincoln Casey

Crephalia n. subgen.

Body long and slender, the facies somewhat as in Metaxya, the middle coxæ very narrowly separated, the mesosternal process short, barely extending to the middle of the coxæ, its apex acute but differing greatly from the usual conformation in not being free, separated from the rather small but anteriorly projecting metasternum, with its apex narrowly rounded, by a moderate undepressed interval, in which the longitudinal ridge is narrowly convex; hind tarsi slender, the basal joint much longer than the second. This will probably prove to be a true genus.

Atheta (Crephalia) recessa n. sp.—Subparallel, slender, rather convex, shining, the punctures very fine, sparse, a little closer and more asperulate on the elytra, the abdominal reticulation rather coarse but feeble; pubescence very inconspicuous; color pale testaceous, the head and a large subapical abdominal cloud blackish, the legs pale; elytra not paler but more flavate; head as long as wide, oval, swollen slightly basally, the tempora very much longer than the eyes, the carinæ obsolete, only visible at base; antennæ moderately short, gradually and rather rapidly, strongly incrassate, the outer joints transverse, the last as long as the two preceding, the second and third moderately elongate, subequal; prothorax very moderately transverse, unimpressed, rather wider subanteriorly than at base but with the sides feebly and subevenly rounded, slightly wider than the head and a little narrower than the elytra, the latter short, with diverging sides, the apices truncate, the suture very distinctly shorter than the prothorax; abdomen long, nearly as wide as the elytra, parallel basally but feebly narrowed apically, the tergites very shining, subequal. Length 1.75 mm.; width 0.33 mm. New York (Catskill Mts.).

A very clearly defined species, to be readily known by its coloration, slender form, oval head and short elytra.

Atheta (Crephalia) prolongata n. sp.—Similar to the preceding in coloration and lustre but a little larger, more elongate and more parallel; head similarly oval and moderately inflated basally, the eyes rather small, not prominent, anterior in position, the carinæ merely basal; antennæ distinctly longer and a little heavier but otherwise similar, except that of the transverse outer joints the tenth is a little less transverse than six to nine, the last large, obtusely pointed, longer than the two preceding; prothorax larger and rather more transverse but similar in form, as wide as the base of the elytra and very much wider than the head; elytra similar though not quite so abbreviated, the suture about as long as the prothorax; abdomen similar but rather longer and more parallel, the apex scarcely narrowed. Length 1.85 mm.; width 0.35 mm. Missouri (St. Louis).

This species is allied to the preceding but differs in its larger prothorax, less abbreviated elytra and longer antennæ.

The following species is slightly aberrant in its shorter abdominal segments and minute size; but the head and tarsi are similar, the sterna, from what can be seen in the single type, homologous, and the antennæ of similar organization though shorter, with the second and third joints much more unequal:

Atheta (Crephalia) testata n. sp.—Subparallel, somewhat convex, shining, the punctures minute and rather sparse, moderately close though scarcely distinct on the elytra, the abdomen coarsely but feebly micro-reticulate, the vestiture fine, not very close; pale brownish-testaceous, the abdomen feebly clouded posteriorly, except at apex, the legs pale; head as long as wide, suboval, the tempora nearly one-half longer than the eyes and more inflated, the carinæ wholly obsolete except at base; antennæ pale testaceous, rather short and stout, gradually though moderately incrassate and compact distally, the outer joints strongly transverse, the last longer than the two preceding, the second and third moderately elongate, mutually similar in form, the latter much the shorter; prothorax only slightly transverse, large and convex, much wider than the head and as wide as the elytral base, somewhat widest before the middle but with the sides distinctly and almost evenly arcuate, the basal angles obtusely rounded, unimpressed; elytra short and transverse, the sides straight and diverging, the suture equal in length to the prothorax; abdomen wide, only slightly narrower than the elytra, parallel, the tergites subequal and short. Length 1.38 mm.; width 0.38 mm. Pennsylvania (Philadelphia).

This species is one of our smallest of the true Athetids; it is probably fungivorous in habits.