Ocypus (Pseudocypus) aereus Cameron , 1928

Smetana, Aleš, 2009, Contributions to the knowledge of the “ Staphylinus-complex ” (Coleoptera: Staphylinidae: Staphylinini) of China. Part 21. The genus Ocypus Leach, 1819, subgenus Pseudocypus Mulsant & Rey, 1876. Section 4, Zootaxa 2286, pp. 1-30 : 23-25

Ocypus (Pseudocypus) aereus Cameron, 1928

( Figs. 57–61 )

aereus Cameron, 1928 , 565 ( Ocypus ; subg. Pseudocypus )

Cameron, 1932, 204 ( Staphylinus ; subg. Pseudocypus ); Scheerpeltz, 1933, 1390 ( Staphylinus ); Scheerpeltz, 1976, 90 ( Staphylinus ); Smetana & Davies, 2000, 43 ( Ocypus ; subg. Pseudocypus ); Herman, 2001, 3362 ( Ocypus ); Smetana, 2004, 677 ( Ocypus ; subg. Pseudocypus ).

Type material. Cameron (1928: 565) described the species from one female taken in Sikkim: Tangu, altitude 11,500 feet (26.iv.1924). The holotype in the Natural History Museum, London, is labeled as follows: “ Holotype ”[round label with red margin] / ”Sikhim: Tangu. 11,500 ft. 26.iv.1924. Maj. R. W. G. Hingston.” / ” Ocypus aereus Cam. TYPE ” [ TYPE in red ink] / ” HOLOTYPE Ocypus aereus Cameron, 1928 det. R. G. Booth 2009". The specimen is pinned, it is in fair condition, right antenna is missing except for two basal segments.

The holotype is the only known female of this species. Due to the frail condition of the holotype, I refrained from dissecting it.

Additional material studied: CHINA: Xizang: “VII b” / ”II. Dolan Expedition WestChina / Tibet leg. E. Schäfer, 1934 / 36” (2) ( ASC, NMW).

Diagnosis. Small-sized species with black appendages, with punctures bearing parascutellar and posteromedian seta on each elytron large, pit-like, with abdominal tergites each bearing shallow impression on each side of midline, and with characteristically shaped aedoeagus.

Description. Entirely black, head, pronotum and elytra with dark greenish metallic lustre, shiny, elytra slightly less so; all appendages uniformly black, except apical portion of each mandible partially paler, dark rufobrunneous; pubescence of dorsal side of body black. Head of obtusely quadrangular shape, with obtuse posterior angles, wider than long (ratio 1. 21), slightly dilated posteriad behind eyes, eyes moderately large, little convex, tempora about as long as eyes from above; dorsal surface of head finely, moderately densely punctate, interspaces between punctures on disc mostly considerably larger than diameters of punctures, punctation becoming much denser on tempora and on lateral portions of posterior margin; more or less appreciable impunctate midline present on posterior half of head; interspaces between punctures without microsculpture. Dorsal side of neck with fine and dense punctation finer and denser that that on head. Antenna short, segments 3 slightly longer than segment 2 (ratio 1.16), segments 4 to 6 slightly longer than wide, becoming gradually shorter, segments 7 to 10 about as long as wide to slightly wider than long, last segment short, considerably shorter that two preceding segments combined. Pronotum as long as wide, slightly narrowed anteriad, moderately convex, narrow marginal groove disappearing downwards at about anterior third of pronotal length; impunctate midline complete, punctation similar to that on disc of head, but denser; interspaces between punctures without microsculpture. Pronotal hypomeron without microsetae. Scutellum densely punctate, with black tomentose pubescence on apical half. Elytra moderately long, slightly dilated posteriad, at suture shorter (ratio 0.81), at sides vaguely shorter (ratio 0.94) than pronotum at midline; punctation very fine, dense, subgranulose, transverse interspaces between punctures mostly about as large as diameters of punctures, without microsculpture; punctures bearing parascutellar and posteromedian seta on each elytron large, pit-like, puncture bearing parascutellar seta smaller than that bearing posteromedian seta. Wings: development unknown. Abdomen with fifth visible tergite without pale apical seam of palisade setae; tergite 2 (in front of first visible tergite) with only a row of setiferous punctures along apical margin; visible tergites 1–5 each bearing shallow impression on each side of midline, punctation of tergites fine, dense, becoming sparser toward apical margin of each tergite, and in general toward apex of abdomen; interspaces with very fine, dense submeshed microsculpture becoming markedly denser and coarser toward lateral margins of each tergite.

Male. Area behind anterior angles of pronotum densely punctate on ground with distinct microsculpture of longitudinal striae. Sternite 8 with moderately wide and deep, obtusely triangular medioapical emargination. Genital segment with tergite 10 densely setose, with almost truncate apex ( Fig. 57 ); sternite 9 short and wide, with narrow, rather long basal portion, apical portion with narrowly arcuate apex ( Fig.58 ). Aedoeagus ( Figs.59–6 l) short, relatively wide, median lobe in ventral view markedly asymmetrical, with right lateral portion markedly triangularly expanded. Paramere situated on median lobe asymmetrically, shaped as in Figs. 59, 60 , with subacute apex not reaching apex of median lobe; underside of paramere lacking sensory peg setae, but with minute sensory setae situated as in Fig. 61 .

Female. Area behind anterior angles of pronotum sparingly punctate on ground with distinct microsculpture of longitudinal striae. There was no female available for dissecting (see Type material), the shape of tergite 10 of genital segment remains therefore unknown for now.

Length 13.0–14.0 mm.

Geographical distribution. Ocypus aereus is at present known from the Himalaya in Nepal ( Scheerpeltz 1976: 90) and Sikkim ( Cameron 1932: 204), and from Xizang (Tibet) in the People’s Republic of China.

Bionomics. Nothing is known about the habitat preferences of this species.

Recognition and comments. Ocypus aereus may be easily recognized by the black coloration of the body and the appendages, combined with the pit-like character of the punctures bearing parascutellar and posteromedian seta on each elytron (see the description for details), and with the presence of the shallow impression on each side of midline of the visible abdominal tergites 1–5.

Figures

FIGURES 57 – 61. Details of Ocypus aereus. 57 — tergite 10 of male genital segment (1.2 mm); 58 — sternite 9 of male genital segment; 59 — aedoeagus, ventral view (1.6 mm); 60 — underside of paramere (1.05 mm); 61 — apical portion of underside of paramere.