Ataenius barberi Cartwright 1974

Ataenius barberi

DESCRIPTION.—Holotype: Length 4.0 mm; width 1.7 mm. Elongate, subparallel, black, the elytra with slight reddish tinge, anterior margins of clypeus and pronotum and legs reddish; feebly shining, the elytra alutaceous, only moderately convex. Head moderately convex; clypeal margin very finely reflexed, sharply dentate each side of wide, shallow median emargination, sides arcuate to obtusely rounded genae; depressed anterior area behind emargination wrinkled and more shining than remainder of head which is densely, moderately punctate; clypeal punctures slightly finer anteriorly, tending laterally to become elongate, twice as wide as long but not forming lines as in A. gracilis, the punctures of the frontal and basal areas are round and very dense across the base, practically touching but remaining distinct. Pronotum 1.6 mm wide by 1.0 mm long, sides weakly arcuate anteriorly, slightly sinuate at the broadly rounded posterior angles; sides and base finely margined, edge minutely crenate, anteriorly becoming increasingly and distinctly so posteriorly with an extremely fine, short seta between the crenations under high magnification; surface everywhere densely, evenly, moderately punctate, the punctures slightly finer at extreme anterior margin and noticeably shallower at sides, median longitudinal line very vaguely indicated. Scutellum normal. Elytra 2.7 mm long by 1.7 mm wide, humeri strongly dentate, striae shining, deep, crenate punctate; intervals subangularly, moderately convex, the ridge at outer third with a row of very fine punctures, separated by about four times their diameters, and more or less masked by fine alutaceous sculpture throughout; sutural interval with row of close, very fine punctures, tenth interval much flatter than others; under high magnification the punctures of the intervals over the apical declivity become setigerous, showing median rows of very fine, very short setae; the striae are somewhat wider apically also. Mesosternum carinate between the coxae. Metasternum shining, midline long, strong; discal area evenly, closely, rather coarsely punctate, separated by about their diameter, finely scabriculate outward to sides, metasternal triangle large, well defined, scabriculate. Abdominal sterna finely fluted in front, suture between very deep and not longer at middle but equally wide from side to side; punctate throughout as on disc of metasternum but 4th and 5th sterna slightly shallower and minutely setigerous; pygidium finely scabrous. Profemur with perimarginal groove, surface scabrous with close, coarse, shallow, finely setigerous punctures and alutaceous sculpture. Punctures of mesofemora and metafemora as on metasternum. Postfemoral line of middle femur complete, strong, deep, and alutaceous. Postfemoral line of hind femur over one-fourth distance from knee. Posterior tibial fringe of eight close, short setae; without accessory spine. First segment of posterior tarsus one-fourth longer than long spur and longer than following three segments combined. Hind tarsus shorter than tibia.

HOLOTYPE.—USNM 71741.

TYPE-LOCALITY.—Arizona, Bright Angel, Colorado Canyon, 3500 ft, 13 July 1901, H. S. Barber.

SPECIMENS EXAMINED.—Seventeen.

DATES COLLECTED.—July 13–16.

DISTRIBUTION (Figure 9).—Paratypes. Arizona (13): Colorado Canyon, 13 July, H. S. Barber and E. A. Schwarz. Texas (3): Chisos Mountains, 16 July, J. W. Green.