Osoriellus diversus, 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 : 252

Osoriellus diversus n. sp.

( Figs 37 A-C, 41D)

Type material: Holotype, male: Peru: Dept. Loreto, Campamento San Jacinto (75°51.77'W, 2°18.75'S), 175-215 m elevation, collected by flight intercept trap, 9.7.1993, leg. R. Leschen ( KNHM).

Paratype: Peru: Madre de Dios, Pantiacolla Lodge , 5.5 km NW El Mirador Trail, Alto Madre do Dios River (71°15.28'W, 12°39.1'S), 500 m elevation, collected by flight intercept trap, male, 23- 26.10.2000, leg. R. Brooks ( UIC); Dept. Loreto, 1.5 km N. Teniente Lopez (76°06.92'W, 2°35.66'S), 210-240 m elvetion, collected by flight intercept trap, male, 20.7.1993, leg. R. Leschen ( KNHM) .

Diagnosis: O. diversus closely resembles O. solidus concerning the polished surface, the obtuse posterior angles of the pronotum and the dense pronotal micropunctation. In contrast to O. solidus , O. diversus is smaller and the posterior angles of the pronotum are more widely rounded.

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

Head: 0.87 mm long, 1.28 mm wide; eyes slightly prominent; longer than temples; fore-head deeply emarginate; sides of clypeus parallel; anterior edge of clypeus widely emarginate; thus, angles slightly produced; punctation deep and irregular; large area on vertex and at base of antennae impunctate; two pairs of setiferous punctures each on both clypeus on line between posterior edge of eyes on supraocular area; punctures on supraocular and postocular area partly coriaceous and striate; much denser than normal punctation; extremely weak remains of microsculpture; surface nearly polished and shiny.

Antennae as long as head and one third of pronotum combined; second antennomere oval and elongate; third conical and slightly shorter than second; fourth antennomere also conical and slightly shorter than third; following antennomeres increasing in width, but all approximately quadrate.

Pronotum: 1.21 mm long, 1.36 mm wide; widest at anterior angles; slightly narrowed in even curve to posterior angles; posterior angles distinct, but obtusely rounded; lateral margin finer in anterior half than in posterior half; in dorsal aspect, not visible close to anterior angles; slightly widened near posterior angles; punctation deep and moderatly dense; on average, interstices between punctures as long as diameter of punctures; without distinct impunctate midline; few setiferous punctures along anterior margin and one pair of setiferous punctures in posterior half; between normal coarse punctation with micro-punctation; very weak remains of netlike microsculpture; surface nearly polished, shiny.

Elytra: 1.47 mm long, 1.45 mm wide; widest in posterior third, but sides nearly parallel; punctation coarse and dense; coriaceous ground-sculpture weak.

Abdomen with sparse punctation on tergites III – VI and weak microsculpture; surface shiny; punctation on tergites VII and VIII much denser and punctures elongate; surface with dense longitudunal reticulate microsculpture; surface matt.

Protibia: 0.78 mm long, 0.21 mm wide; 8 spines on outer edge; apical 4 spines inserting on long teeth; WLR: 0.57; in posterior aspect, inner emargination with comb distinctly visible throughout its total length; posterior face sparsely covered by long yellow setae.

Aedaegus with thick basal and apical lobe; apex of apical lobe thick and obtusely rounded; four sensillae at apex and row of sensillae at inner edge of apical lobe.

Etymology: The specific name diversus derives from the same Latin word and means different. It refers to the varying size of punctures on the pronotum.

Figures

Fig. 32-37: Osoriellus-guiananus-group: Osoriellus guiananus (32), O. breviceps (33), O. solidus (34), O. macrops (35), O. melancholicus (36), O. diversus (37); antenna (A), protibia (B), aedeagus in lateral aspect (C); scale bar: 0.1 mm.