Osoriellus mrazi, Irmler, 2014

Irmler, Ulrich, 2014, The Neotropical species of the genus Osoriellus FAGEL, 1959 (Coleoptera: Staphylinidae: Osoriinae), Beiträge Zur Entomologie = Contributions to Entomology 64 (2), pp. 231-354 : 257

Osoriellus mrazi n. sp.

( Figs 40 A-D, 42B)

Type material: Holotype, male: Brazil: Såo Paulo, leg. Jaro K. Mraz ( NMP).

Diagnosis: The species cannot be placed to one of the other groups. It is characterised by the normally coarse punctation of the pronotum, the short teeth at clypeal angles and the long digits of the protibia. It resembles to the species of the O.- guiananus - and the O.- laeviusculus -group concerning the absence of the pubescence of the fore-body. But compared to both groups, the eyes are not prominent and the pronotum is without dense microsculpture.

Description: Length: 6.4 mm. Colouration: Black; legs and antennae brown.

Head: 0.97 mm long, 1.44 mm wide; eyes moderately large; not prominent; slightly longer than temples; sides of fore-head deeply emarginate; sides of clypeus parallel; anterior edge of clypeus with broadly produced angles; at inner side, adjacent to angles with acute triangular teeth; between teeth widely emarginate; punctation irregularly dense; not pubescent; small area on posterior vertex and large area at base of antennae impunctate; pair of indistinct impressions on posterior vertex and one indistinct impression in centre of anterior vertex; supraocular punctures partly granulate; on supraocular area with several striae; without microsculpture; surface polished and shiny.

Antennae slightly longer than head; second antennomere oblong; third antennomere conical and slightly longer than second; following antennomeres slightly longer than wide; tenth antennomere slightly wider than long.

Pronotum: 1.27 mm long, 1.52 mm wide; widest at anterior angles; anterior angles slightly produced to short teeth; sides convergent in even convex curve; posterior angles obtuse; lateral margin moderately fine; in dorsal aspect, visible throughout its total length; punctation deep and dense; without pubescence; irregularly dense; on average, interstices between punctures as wide as diameter of punctures; moderately wide midline impunctate; between coarse punctures with sparse micro-punctation; indistinct depressions on transverse line in middle; without microsculpture; surface polished and shiny.

Elytra: 1.44 mm long, 1.47 mm wide; with weak groundsculpture; punctures distinctly visible.

Abdomen with setiferous punctation; wide midline on tergites impunctate; with microsculpture; surface shiny.

Protibia: 0.80 mm long; 0.26 mm wide; with 7 spines at outer edge; four apical spines inserted on long digits; WLR: 0.45; posterior face with few long setae.

Aedeagus with broad apical lobe; sinuate near apex; apex obtuse; inner edge at base with six sensillae.

Etymology: The specific name derived from the collector of the species, Jaro Mráz.

Figures

Fig. 38-40: Osoriellus-guiananus- and -mrazi-group:Osoriellus longipunctatus (38), Osoriellus silvaticus (39), O. mrazi (40); antenna (A), protibia (B), aedeagus in lateral aspect (C), clypeus (D); scale bar: 0.1 mm.