Ataenius utahensis Cartwright 1974

Ataenius utahensis

DESCRIPTION.—Holotype Male: Length 3.9 mm; width 1.6 mm. Elongate, parallel, shining, dark reddish brown. Head convex, finely reflexed clypeal margin, sharply, triangularly dentate each side of moderate median emargination, sides weakly arcuate, genae obtusely right-angled; surface coarsely, transversely rugose anteriorly below greatest convexity, upper clypeus smooth to minutely punctate shading to very fine across upper front. Pronotum quadrate, 1.5 mm wide and 1.1 mm long, convex lateral margin not visible from directly above, anterior angles obtusely rounded, posterior angles very broadly rounded, sides and base finely margined, lateral setae very minute, scarcely discernible; surface closely punctate throughout, the punctures moderate at middle of disc, separated by a little less than their diameter, very gradually finer away in all directions especially anteriorly, except in the lateral foveae and anterior angles where the punctures become noticeably larger and practically contiguous. Elytra 2.5 mm long and 1.6 mm wide, convex, humeri finely dentate, striae moderately deep, fine strial punctures weakly crenating the inner margin of the convex intervals, a row of very fine punctures along outside margin, those of the outside intervals slightly more noticeable, shoulders noticeably punctate, outside intervals otherwise not different. Mesosternum shagreened as usual with fine, close punctures and short, fine, decumbent hairs, broadly carinate between the coxae. Metasternal midline long and deep, disc with scattered, very moderate punctures, slightly smaller posteriorly, separated by about one diameter, finely scabrous from halfway to sides, metasternal triangle with a small scabrous spot at anterior angle. First visible abdominal sternum with posterior marginal line, remaining sterna very finely, narrowly fluted along anterior margin, the fluting much wider on penultimate sternum, middle three sterna evenly, moderately punctate from side to side, the punctures separated by one or two diameters, punctures of terminal sternum much closer and smaller, penultimate sternum shortened at middle, about two-thirds as long as at sides. Pygidium very finely punctate at apex, eroded gradually more deeply to base. Anterior femur with perimarginal groove, anteriorly with minute, scattered punctures, gradually larger and transversely elongate posteriorly. Middle and posterior femora shining, with scattered, minute punctures, posterior marginal line reduced to a mere trace at knee. Apical fringe of posterior tibia of seven or eight fine setae, without accessory spine, first tarsal segment shorter than long spur and three following segments combined.

Allotype Female: Length 3.4 mm; width 1.4 mm. Differs from the male in penultimate abdominal sternum not shortened at middle and the pygidium wider.

Paratypes vary in length from 3.4 to 4.1 mm. The clypeus appears impunctate or very minutely punctate.

HOLOTYPE.—USNM 71750.

TYPE-LOCALITY.—St. George, Utah, A. M. Woodbury collector (Wickham Collection).

SPECIMENS EXAMINED.—Six.

DATE COLLECTED.—October 1.

DISTRIBUTION (Figure 11).—Paratypes and allotype. Zion Park, Utah (5), 1 October 1934, Bryant.