Osorius sinuatocollis 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 : 401-402

Osorius sinuatocollis BERNHAUER ,, 1920: 139 (Figs 19 a-b)

Type material examined:

Brazil: A female without further data (holotype, FMNH) .

Diagnosis:

The species is easy to distinguish, because of the characteristic shape of the pronotum with the deep emargination in front of the posterior angles. Unfortunately, only the female type specimen could be studied.

Description:

Length: 10.5 mm. Colour: black.

Head :: 1.5 mm long, 2.2 mm wide; punctation moderately dense and deep; on clypeus with very few indistinct punctures; partly with dense and coriaceous punctation on disc; a small circular depressions on central disc and at antennal base impunctate; punctate space with isodiametric microsculpture; surface slightly shiny; clypeus with obtusely prominent angles; labrum relatively long; labrum distinctly projecting clypeal emargination; eyes slightly shorter than temples; with supraocular and postocular striae and granular punctures; striae behind eyes pointing ventrad; with several supraocular setae.

AntennaeAntennae elongate with 3 rd antennomere conical and nearly two times longer than 2 nd; antennomeres 4 to 6 longer than wide; subsequent antennomeres quadrate.

Pronotum: 2.0 mm long, 2.4 mm wide; widest at tooth-like prominent front angles; continuously, but only slightly narrowed behind front angles; in posterior third distinctly emarginate; posterior angles nearly rectangular; lateral margin at front angles narrow; distinctly wider at posterior angles; posterior edge margined; punctation moderately dense and deep; distance between punctures on average as wide as diameter of punctures; with weak isodiametric microsculpture; surface shiny; a long longitudinal depression within smooth midline; with longer distance from front edge than from posterior edge.

Elytra: 2.3 mm long, 2.4 mm wide; with coriaceous ground sculpture; moderately dense and deep punctation scarcely visible between deep ground sculpture.