Ataenius scabrelloides Petrovitz 1962

Ataenius superficialis

DESCRIPTION.—Holotype Male: Length 3.6 mm; width 1.7 mm. Oblong-ovate, convex, covered with a gray argillaceous coating which does not adhere to the surface as tightly as in imbricatus, legs and anterior margin of clypeus reddish. Head convex, clypeal edge finely, not strongly reflexed, margin broadly rounded each side of a moderately deep median emargination, sides weakly arcuate to depressed, nearly right-angled genae; surface concave, smooth, shining, dark castaneous behind emargination, then above very quickly, closely from minute to shallowly coarsely punctate, the intervening spaces finely alutaceous, from middle of disc to sides and base the punctures are setigerous, larger, become elongate, crowded, many uniting to form lines, especially near front, the setae are very short and inconspicuous; front and occipital area densely covered with shallow, coarse, round punctures showing through the argillaceous coating, frontal-clypeal suture in part bare and unusually distinct. Pronotum 1.5 mm wide and 1.1 mm long, anterior angles obtuse, hind angles broadly rounded, sides feebly arcuate, sides and base without distinct marginal groove but sides very finely reflexed, sides and base with very short, stubby marginal setae separated at sides by twice their length, a little closer opposite humeri; surface everywhere with dense, coarse, setigerous punctures, the setae minute and inconspicuous, punctures a little finer near anterior margin; a flat, smooth, minutely alutaceous midline over posterior half and a short, dark, uncoated spot midway to sides, just posterior to midpoint between anterior and posterior margins. Elytra 2.4 mm long and 1.7 mm wide, convex, ovate, widest beyond middle, humeri finely dentate, striae deep, wide, mostly shining, except for deep strial punctures, the punctures not crenating the sides of the moderately convex intervals, each interval with a row of short, stubby setae along outside margin, occasionally a few setae along inner margin also, elytral margin with similar setae, the tenth interval not as convex. Mesosternum shagreened, with fine sculpture and the usual very fine, short, decumbent hair, sharply carinate between the coxae. Metasternal disc coarsely, closely, shallowly punctate, midline long, shallow, surface rough and scabrous outward to sides, metasternal triangle weakly developed, masked by rough sculpture. First visible abdominal sternum with fine posterior marginal line, remaining four sterna with fine fluting along anterior margin, longer on each following sternum, flutings of 5th sternum nearly half as long as sternum, surface very closely, shallowly, coarsely punctate with punctures within and surrounding area very finely alutaceous. All coarse punctures of underside minutely setigerous under high magnification. Pygidium with apical smooth margin very fine or possibly absent, surface otherwise finely, roughly alutaceous (covered by argillaceous coating in holotype). Fourth abdominal sternum half as long as preceding sternum; pygidium much longer than in female. Anterior femora with perimarginal groove, surface closely, very roughly sculptured, some setae visible in profile. Middle femora minutely alutaceous and coarsely, shallowly, setigerously punctate, the outer half closely, roughly punctate, posterior marginal line strong, deep, complete, with a marginal row of widely spaced, short, stubby setae. Posterior femora similar in every way except that the coarse punctures are generally separated by about twice their diameters and there are three or four long, stiff setae near the knee. Apical fringe of posterior tibia of four or five short, well-separated setae, without accessory spine. (The normal number of setae is five, with the middle one about half as long as the other four.) First segment of posterior tarsus noticeably longer than the long spur, the following three segments combined shorter than the long spur.

Allotype Female: Length 3.6 mm; width 1.7 mm. About the only differences from the male seem to be the longer 4th sternum and shorter pygidium. The allotype is almost completely denuded of the argillaceous coating, and surface sculpture can be seen much more clearly.

HOLOTYPE.—USNM 71737.

TYPE-LOCALITY.—Big Pine Key, Florida. Holotype, allotype, and five paratypes collected together under animal dropping (possibly from a racoon), 15 May 1959, O. L. Cartwright.

SPECIMENS EXAMINED.—Seven.

DATE COLLECTED.—May 15.

DISTRIBUTION (Figure 8).—Paratypes. Florida: Big Pine Key.