Osoriosetus, Irmler, 2015

Irmler, Ulrich, 2015, New Neotropical genera and species of the tribe Osoriini (Coleoptera: Staphylinidae: Osoriinae), Beiträge Zur Entomologie = Contributions to Entomology 65 (1), pp. 173-196 : 175

Osoriosetus gen. nov.

Type species: Osoriosetus hanagarthi spec. nov., here designated as the type species for the genus.

Etymology: The generic name is a combination of the words Osorius that refers to the relation to the Osorius complex and setus referring to the densely setose posterior face of the protibia.

Description: Length & habitus: elongate; typical habitus of genera of Osorius complex; moderately large species of about 5 to 6 mm.

Head approximately quadrate; sides in front of eyes sinuate; labrum rectangular; eyes well developed; setiferous punctation; setae short; few longer supraocular and praeocular setae; without distinct neck; neck separated from vertex by absence of punctation.

Antennae geniculate; antennomeres increasing in width from base to apex.

Pronotum subparallel; emarginate in front of posterior angles; lateral margin fine, of equal width throughout its total length; setiferous punctation coarse.

Elytra approximately quadrate; shoulders nearly rectangular; suture present; setiferous punctation in irregular rows.

Abdomen with all tergites densely and coarsely punctate; punctures setiferous.

Protibia extremely enlarged; semicircular, posterior face setose; without spines; outer edge of protibia with more than 10 spines; in posterior aspect, comb and emargination of inner edge completely covered; in posterior aspect without inner emargination; inner edge straight.

Aedeagus without endophallus; apical lobe curved; paramera absent.

Diagnosis: The genus is closely related to the genera Antillosorius IRMLER, 2010b and Osoriellus FAGEL, 1959 concerning the setose posterior face and the absence of spines on the posterior face of the protibia. As in Osoriellus , the lateral margin of the pronotum is equal in width, which separates Osoriosetus and Osoriellus from Antillosorius . The specific semicircular shape of the protibia is unique in the genera of the Osorius complex and justifies establishing a new genus. At present, the genus is only known from South-America.