Osoriellus coruscus, 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 : 263-264

Osoriellus coruscus n. sp.

( Figs 45 A-C, 95C)

Type material: Holotype, male: Brazil: Rio de Janeiro, Paulo a Virginia , 10.8.1958, leg. R. Arlé (377) ( INPA).

Paratype: Brazil: female with same data as holotype ( UIC) .

Diagnosis: The species resembles O. exiguus in size and shape of the pronotum. In addition to the differences mentioned below in the diagnosis of O. exiguus , the shape of the aedeagus slightly differs from that of O. exiguus . In O. coruscus the apical lobe is short and thick and the apex truncate, whereas it is elongate in O. exiguus .

Description: Length: 2.6 mm. Colouration: Dark yellow; posterior margin of elytra light brown; legs and antennae light yellow.

Head: 0.35 mm long, 0.47 mm wide; eyes small; not prominent; temples twice as long as eyes; side of fore-head more or less evenly convergent to front angles of clypeus; angles of clypeus produced to short teeth; setiferous punctation of clypeus sparse; punctation of vertex much denser and deeper, but with wide impunctate midline; microsculpture weak; laterad deeper and denser; midline without microsculpture; surface shiny; supraocular area less shiny than vertex.

Antennae slightly longer than head; second antennomere thick and oblong; thicker than antennomeres 3 to 5; third antennomere conical; only half as long as second; fourth to fifth antennomeres approximately quadrate; sixth antennomere wider than long; following antennomeres distinctly wider than preceding antennomeres and increasing in width; 1.5 times as wide as long.

Pronotum: 0.45 mm long, 0.50 mm wide; widest at anterior angles; slightly narrowed to smoothly rounded posterior angles; lateral margin narrow; in dorsal aspect, not visible near anterior angles; setiferous punctation as deep and dense such as on posterior head; on average, interstices between punctures less than half as wide as diameter of punctures; without microsculpture; surface polished and shiny.

Elytra: 0.60 mm long, 0.50 mm wide; with coarse and deep setiferous punctation; ground-sculpture distinctly coriaceous and deep; punctation scarcely visible; surface matt. Abdomen with deep and coarse setiferous punctures; tergites without basal impression; punctation on segments VII and VIII slightly less dense than on preceding segments; anterior segments matt; segments VII and VIII slightly shiny.

Protibia: 0.27 mm long, 0.07 mm wide; 8 long spines on outer edge; apical spines not inserted on digits; WLR: 2.0; in posterior aspect, comb of inner emargination totally visible; posterior face with sparse setation; setae approximately half as long as protibial width.

Aedeagus thick; with short and stout apex; apical lobe smoothly curved.

Etymology: The specific name coruscus derived from the same Latin word meaning shiny and refers to the shiny surface of the pronotum.

Figures

Fig. 43-47: Osoriellus-s. str.-group: O. exiguus (43), Osoriellus indescriptus (44), O. coruscus (45), O. luteus (46); O. punctatellus (47); antenna (A), protibia (B), aedeagus in lateral aspect (C); scale bar: 0.1 mm.