Platydracus (Platydracus) juang Smetana

Smetana, Aleš, 2005, Contributions to the knowledge of the “ Staphylinus­complex ” (Coleoptera, Staphylinidae, Staphylinini) of China. Part 10. A new species of the genus Platydracus Thomson, 1858, Zootaxa 1048, pp. 21-25 : 22-23

Platydracus (Platydracus) juang Smetana , sp. nov.

( Figs. 2–4 )

Type material. Holotype (female): China: “ China, N Fujian, 1.– 4.VI. FENGSHUI GUAN 27.9N 117.85E, ~ 1700 m Jaroslav Turna leg. 2004". In the Naturhistorisches Museum, Wien, Austria.

Description. Entirely deep black; maxillary and labial palpi piceous­black, apices of last segments slightly paler; antennae and legs uniformly black. Head of rounded quadrangular shape, vaguely dilated behind eyes toward broadly rounded, entirely obsolete posterior angles, wider than long (ratio 1.21); eyes moderately large, moderately convex, tempora longer than eyes from above (ratio 1.36); disc of head slightly depressed anteriorly and with a similar but smaller depression on each side posteromediad of each eye; tempora densely and moderately coarsely punctate, punctation of disc becoming gradually sparser anteriad and toward vaguely indicated impunctate midline, coarse punctures intermixed with very fine punctures; pubescence black; surface between punctures without microsculpture. Antenna short and robust, segments 2 and 3 subequal in length, segment 4 slightly, segments 5 to 10 distinctly transverse, gradually incrassate, last segment short, shorter than two preceding segments combined. Pronotum slightly longer than wide (ratio 1.10), almost parallelsided, narrow marginal groove disappearing downwards just in front of middle of pronotal length; disc with inconspicuous impunctate midline; punctation and pubescence similar to that on head, but punctation slightly sparser and finer, surface between punctures without microsculpture. Scutellum with dense rugulose punctation and black pubescence, surface without microsculpture. Elytra moderately long, at suture about as long as, at sides slightly longer (ratio 1.1) than pronotum at midline; punctation dense, moderately coarse and slightly rugulose, interspaces between punctures without microsculpture; pubescence black, becoming paler behind humeri and along lateral margins. Wings fully developed. Abdomen with fifth visible tergite bearing distinct, pale apical seam of palisade setae; tergite two (in front of first visible tergite) impunctate, except for some fine punctures along apical margin; first four visible tergites impressed at base; basal impressions with coarse, rugged punctation, rest of each tergite with fine and sparse punctation becoming gradually sparser toward apex of abdomen; surface between punctures without microsculpture; pubescence piceous, becoming paler toward lateral margins of tergites.

Female. Tergite 10 of genital segment relatively narrow, markedly narrowed toward subacute apex, densely setose medioapically ( Fig. 2 ).

Length 15.0 mm.

Geographical distribution. Platydracus juang is at present known only from the type locality in Wuyi Shan in northern Fujian.

Bionomics. Nothing is known about the collecting circumstances of the holotype.

Recognition and comments. Platydracus juang differs from P. brachycerus by the larger size and more robust body, by the larger and wider head that is entirely, broadly rounded posteriorly, by the denser punctation of the head, by the longer pronotum, by the coarser punctation in the basal impressions of the first four visible abdominal tergites and by the finer and sparser punctation on the rest of the tergites, and by the markedly different shape of tergite 10 of the female genital segment ( Figs. 1, 2 ).

The spelling of the type locality on the label is not quite correct. It should read Fenshui Guan.

Etymology. The specific epithet is the Chinese word juang (big, strong, stout). It refers to the appearance of the species in comparison with P. brachycerus .

Figures

FIGURES 1 – 2. Tergite 10 of female genital segment of (1) Platydracus brachycerus, and (2) Platydracus juang.

FIGURES 3 – 4. Platydracus juang: habitus (3), and detail: head and pronotum (4).