Osoriellus laeviusculus ( BERNHAUER, 1920 ), 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 : 235

Osoriellus laeviusculus ( BERNHAUER, 1920) new combination

( Figs 3 A-B, 5B)

Osorius laeviusculus BERNHAUER, 1920: 9

Type material examined: Brazil: Santa Catharina, female without further date, leg. Klimsch (holotype in FMNH).

Further material examined: Brazil: São Paulo, 2 females, without further data, leg. J. Mráz ( NHMP).

Diagnosis: Concerning the absence of the setiferous punctation and the impunctate pronotal midline, the species is most related to O. schubarti . It can be differentiated from that species by the smaller size and the even anterior margin of the clypeus.

Description: Length: 4.8 mm. Colouration: black, posterior edge of pronotum reddish, elytra dark brown, legs and antennae yellow.

Head: 0.55 mm long, 0.90 mm wide; front edge of the clypeus even; clypeal angles produced into short teeth; eyes large and prominent, nearly twice as long as temples; with several supraocular setae and a fine punctation; interstices between punctures on average as wide as or slightly wider than diameter of punctures; punctures without setae; with fine and dense transverse microsculpture; surface nearly dull.

Antennae with first antennomere as long as following three, second antennomere oval and as long as conical third one; antennomeres four to six more or less quadrate; the following 4 antennomeres much larger and wider than long.

Pronotum: 1.00 mm long, 1.00 mm wide; widest at anterior edge; anterior angles not prominent; sides slightly narrowed to posterior angles; nearly parallel in the anterior half; stronger narrowed shortly in front of the posterior angles: lateral margin extremely fine; punctation deeper than on head, but sparser; interstices between punctures on average twice as wide as diameter of punctures; a moderately wide midline impunctate; on central disc, on each side of the midline with circular depression; microsculpture longitudinal; surface slightly shiny, more shiny than surface of head.

Elytra: 1.10 mm long, 1.00 mm wide; with weak coriaceous ground-sculpture and fine and sparse punctation; punctures without setae; surface slightly shiny.

Abdomen finely and sparsely punctate; punctures with short yellow setae pointing to the middle; wide midline impunctate.

Protibia: 0.53 mm long, 0.13 mm wide; with 7 spines on outer edge; apical spine on moderately long digits; WLR: 0.70; in posterior aspect, comb at inner emargination visible throughout ist total length; on anterior face with row of five setae; posterior face sparsely covered with long yellow setae.

Aedeagus unknown.

Figures

Fig. 2-4: Osoriellus-coronatus- and –laeviusculus-group: Osoriellus coronatus (2), O. laeviusculus(3), O. schubarti (4); antenna (A), protibia (B), aedeagus in lateral aspect (C), anterior edge of clypeus (D), abdominal segment VII (E); scale bar: 0.1 mm.