Osorius dentatus BERNHAUER

Irmler, Ulrich, 2010, The Neotropical species of the genus Osorius G - M, 1829 with remarks to the Neotropical Osoriid complex (Coleoptera: Staphylinidae: Osoriinae), Beiträge Zur Entomologie = Contributions to Entomology 60 (2), pp. 363-426 : 384-385

Osorius dentatus BERNHAUER ,, 1908: 294 ( Figs 11 a-d, 38 C)

Type material examined:

Bolivia: Mapiri (68.09 W, 15.15 S) 1 male without further data (holotype, FMNH) .

Diagnosis:

Concerning size, O. dentatusdentatus is nearly as small as O. costaricensis , O. paganus and O. sublaevis , but microsculpture of pronotum is weaker and surface shinier in O. dentatus . Moreover, a micropunctation exists on the pronotum that is not found in the other species of similar size. A shiny pronotal surface is also found in O. wasmanni , but O. wasmanniwasmanni is much larger (9.5 mm) and with a distinct longitudinal depression in the midline of the pronotum.

Description:

Length: 7.2 mm. Colour: black; elytra slightly lighter; dark brown.

Head :: 1.1 mm long, 1.3 mm wide; deeply and densely punctate; distance between punctures on average shorter than diameter of punctures; isodiametric microsculpture deep; surface slightly shiny; front angles of clypeus shortly prominent; at inner side diagonally retreated and with few short setae; labrum short, scarcely projecting clypeal emargination; eyes, as large as temples, semi-circularly projecting head; with several short supraocular and postocular striae and granular punctures; with two supraocular setae.

AntennaeAntennae with 2 nd antennomere oval; 3 rd one conical and as long as 2 nd; antennomeres 4 and 5 slightly longer than wide; subsequent ones quadrate.

Pronotum: 1.4 mm long, 1.6 mm wide; widest at tooth-like front angles; sides continuously narrowed to posterior angles; lateral margin narrow at front angles and only slightly wider at posterior angles; posterior angles more or less obtusely rounded; front and posterior edge margined; punctation deep and dense; distance between punctures on average as wide as or shorter than diameter of punctures; with large smooth midline; more or less isodiametric microsculpture weak; surface nearly polished.

Elytra: 1.6 mm long, 1.5 mm wide; with coarse punctation; scarcely visible between deep coriaceous ground sculpture; an indistinct longitudinal depression behind shoulders on disc.

AedeagusAedeagus nearly quadrate with long, curved apical part ending in acute apex.

Figures

Fig. 11: Osorius dentatus. - Fig. 12: O. costaricensis. - Fig. 13: O. verhaagi (a: front body, b: antenna, c: aedeagus in ventral and lateral aspect; scale bar: a, b: 1 mm, c, d: 0.5 mm).