Osoriellus asperatus, 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 : 259-260

Osoriellus asperatus n. sp.

( Figs 67 A-C, 95F)

Type material: Holotype, male : Brazil: Amazonas, Manaus, INPA/Smithsonian Reserve 2 (59°50'W, 2°25'S), leaf litter of terra firme forest, collected by Winkler method, male, January 1994, leg. R. Didham ( BMNH).

Paratypes: Brazil: with same data as for holotype, 3 females, 1 male, January 1994, February 1994, March 1994 ( BMNH, UIC); Reserva Ducke , 26 km NE of Manaus, flight intercept trap, female, 1995-1996 ( BMNH) .

Diagnosis: The species is characterised by the dense coriaceous punctation of the pronotum that is so far unique in the Neotropical Osoriellus species.

Description: Length: 3.4 mm. Colouration: Black, anterior half of elytra dark red.

Head: 0.43 mm long, 0.69 mm wide; eyes thick and distinctly prominent; nearly twice as long as temples; sides of fore-head convergent to anterior angles; not sinuate; anterior edge of clypeus even; extremely dense setiferous punctation deep and coariaceous; interstices between punctures less than one fifth as wide as diameter of punctures; yellow setae long; only small area at base of antennae impunctate.

Antennae slightly shorter than head and half of pronotum combined; second antennomere oval and distinctly thicker than third antennomere; 1.5 times as long as third antennomere; following antennomeres increasing in width; third and fourth antennomeres approximately quadrate; following antennomeres wider than long; eighth antennomere 1.5 times as wide as long; tenth antennomere only slightly wider than long; surface matt.

Pronotum: 0.67 mm long, 0.70 mm wide; widest near anterior angles; sides approximately parallel in anterior half; in posterior half, more strongly and evenly narrowed to posterior angles; slightly sinuate shortly in front of posterior angles; posterior angles nearly rectangular; lateral margin fine; in posterior half, slightly wider than in anterior half; in dorsal aspect, hardly visible in anterior half; extremely dense setiferous punctation deep and coarse; partly coriaceous; punctures larger than on head; interstices between punctures one fifth as wide as diameter of punctures; wide, parallel midline impunctate; yellow setae at least as long as three times of diameter of punctures; without microsculpture; surface matt.

Elytra: 0.78 mm long, 0.75 mm wide; widest near middle; shoulders nearly rectangular; setiferous punctation less dense than on head and pronotum, but also deep and coarse; on average, interstices between punctures as wide as half of diameter of punctures; on average, yellow setae as long as double diameter of punctures; coriaceous ground-sculpture weak; surface matt.

Abdomen as densely and deeply punctate as fore-body; surface matt.

Protibia: 0.34 mm long, 0.12 mm wide; with 7 long spines on outer edge; apical spines inserted on short and wide digits; WLR: 3.1; in posterior aspect, comb at inner emargination totally visible; posterior face with moderately dense setation; yellow setae approximately as long as half of width of protibia.

Aedaegus with thick basal lobe and short and thick apical lobe; apical lobe narrowed to obtuse, widely rounded apex; on inner edge of apical lobe, one sensilla in apical third and four sensillae in basal third.

Etymology: The specific name derived from the same Latin word meaning coarse and refers to the coarse punctation of the species.

Figures

Fig. 63-67: Osoriellus-s. str.-group:Osoriellus humicola(63), O. parumpunctatus (64),O. obtusicollis (65),O. tuxtlae(66),O. asperatus (67); antenna (A), protibia (B), aedeagus in lateral aspect (C); scale bar: 0.1 mm.