The Neotropical species of the genus Osoriellus FAGEL, 1959 (Coleoptera: Staphylinidae: Osoriinae) Author Irmler, Ulrich text Beiträge Zur Entomologie = Contributions to Entomology 2014 2014-12-15 64 2 231 354 https://www.contributions-to-entomology.org/article/view/1859 journal article 2515 10.21248/contrib.entomol.64.2.231-354 5df8bd34-9c04-4499-afe0-018387e11ffb 0005-805X 5461706 Osoriellus bicornis n. sp. ( Figs. 14 A-D, 20A) Type material : Holotype , male : Peru : Tambopata Prov. , Madre de Dios Dpto. , 15 km NE Puerto Maldonado , Reserva Cuzco Amazónico ( 12°33'S , 69°03'W ), 200 m elevation, Z2 E15, flight intercept trap , 26.6.1989 , leg. D. Silva & R.A. Leschen , #285 ( KNHM ). Diagnosis : The species can be easily identified by the produced truncate teeth of the clypeus. The other species with teeth-like produced angles of the clypeus are longer than 4 mm and teeth are acute. Description : Length : 3.7 mm . Colouration : Light brown, except fore-head; posterior head darker brown; legs and antennae yellow. Head : 0.56 mm long, 0.71 mm wide; eyes distinctly prominent; as long as temples; sides of fore-head narrowed to front edge in concave curve; anterior angles of clypeus produced to broad truncate teeth; teeth longer than onefourth of distance between them; setiferous punctation irregularly dense and deep; on vertex denser than on forehead; wide midline, area at base of antennae and transverse area on posterior vertex impunctate; on average on punctate areas, interstices between punctures distinctly shorter than diameter of punctures; with remains of weak microsculpture; surface slightly shiny. Antennae as long as head and half of pronotum combined; second antennomere oblong; wider and nearly twice as long as conical third antennomere; following antennomeres increasing in width; fourth quadrate; fifth and sixth wider than long; sixth antennomere twice as wide as long; antennomeres 7 to 10 distinctly wider than preceding antennomeres and quadrate. Pronotum : 0.67 mm long, 0.71 mm wide; widest at anterior angles; anterior angles shortly produced to acute teeth; sides evenly convergent to smoothly rounded posterior angles; in anterior half less narrowed than in posterior half; lateral margin fine; in posterior half slightly wider; in dorsal aspect, not visible close to anterior angles; setiferous punctation deep and sparser than on vertex of head; in irregular longitudinal rows; midline impunctate; on average, interstices between punctures of rows as wide as diameter of punctures; interstices between punctures wider than diameter of punctures; microsculpture deep, but not dense; surface slightly shiny. Elytra : 0.87 mm long, 0.75 mm wide; setiferous punctation distinct; in rows; coriaceous ground-sculpture weak; surface less shiny than on pronotum and head. Abdomen with dense setiferous punctation; without impunctate midline; interstices between punctures with weak netlike microsculpture; surface shiny. Protibia : 0.39 mm long, 0.11 mm wide; with 8 spines at outer edge; apical spines not inserted on digits; WLR: 3.5; in posterior aspect, comb at inner emargination nearly invisible in central part, but with very long setae at base; posterior face sparsely covered by yellow setae. Aedeagus with smoothly curved apical lobe ending in obtuse apex; inner edge of apical lobe with row of sensillae in regular distances. Etymology : The specific name derived from the Latin word meaning two horns and refers to the two horn-like truncate teeth of the clypeus.