Bisnius lubricus, 2011

Li, Liang & Zhou, Hong-Zhang, 2011, Revision and phylogenetic assessment of the rove beetle genus Pseudohesperus Hayashi, with broad reference to the subtribe Philonthina (Coleoptera: Staphylinidae: Staphylinini), Zoological Journal of the Linnean Society 163 (3), pp. 679-722 : 715-716

BISNIUS LUBRICUS LI & ZHOU SP. NOV. ( FIG. 30A–F )

Type material: Holotype: ♂, China: Sichuan: Ganzi: Hailuogou (29°55′N, 102°15′E), 3000 m asl, 16.v.2009, Zhou Yulingzi collected (IZ-CAS); paratypes: 2 ♂♂, same data as holotype (IZ-CAS).

Description: Body black, shining. Elytra with strongly metallic lustre. Abdomen with strongly iridescent lustre. Mandibles, maxillary and labial palpi dark brown.

Body 7.59–8.32 mm long ( HPL: 2.37–2.45 mm). Head of rounded quadrangular shape, slightly narrowed posteriad, 1.06–1.14 mm long, 1.06 mm wide, almost as long as wide ( HW: HL = 0.93–1.00). Lateral and medial interocular punctures distant, distance separating medial punctures slightly smaller than distance separating medial punctures from lateral punctures. Tempora 0.41 mm long, almost evenly rounded, with scattered, large setiferous punctures; eyes moderately large, slightly prominent, 0.33– 0.41 mm long, 0.80–1.00 times as long as tempora. Dorsal surface of head with distinct and profound microsculpture of specialized short lines. Antennae moderately long, antennomere I very long, thickened towards apex, antennomere III distinctly longer than antennomere II, antennomeres IV–V slightly longer than wide, antennomere VI almost as long as wide, antennomeres VII–X slightly transverse, antennomere XI distinctly longer than wide, obliquely truncated.

Pronotum slightly narrowed anteriad, 1.06– 1.14 mm long, 1.06–1.14 mm wide, slightly wider than head ( PW: HW = 1.00–1.08); dorsal rows on pronotum each with four large punctures, sublateral rows each with two punctures; microsculpture fine, similar to that on head.

Elytra slightly widened posteriad, 1.47–1.63 mm long, 1.47–1.55 mm wide, along sides 1.38–1.43 times as long as pronotum, sparsely and largely punctate, punctures separated by three to five times their diameter. Scutellum large, triangular, densely and finely punctate.

Abdomen a little narrowed posteriad, widest 1.39–1.55 mm; each tergite only with a few scattered punctures, frequently almost impunctate; surface between punctures without microsculpture of transverse striae. Tergites III–VI with two basal carinae, elevated area between basal carinae almost impunctate.

Male: Sternite VIII with moderately wide, obtusely triangular medioapical emargination ( Fig. 30E ). Genital segment with stylus of tergite IX simple, moderately setose apically. Sternite IX with more or less symmetrical basal portion, apex deeply emarginate ( Fig. 30D ). Tergite X simple, triangular, subrounded at apex, with numerous apical setae ( Fig. 30F ).

Aedeagus with median lobe narrowed into subacute apex ( Fig. 30A ); in lateral view, apical portion of median lobe slightly bent dorsad (parameral side) ( Fig. 30B ); paramere large, shorter than median lobe, bilobed, lobes long, narrowly separated from each other at base; face adjacent to median lobe with sensory peg setae, closely arranged along inner lateral margin of paramere ( Fig. 30C ).

Female: Unknown.

Etymology: The specific epithet is derived from the Latin word lubric- (smooth), and refers to the sleek abdomen.

Distribution: At present known only from China (Sichuan).

Remarks: The new species is similar to Bisnius xuae Li & Zhou, 2010a . Bisnius lubricus Li & Zhou sp. nov. can be easily distinguished from B. xuae by slightly wider head, sparser punctures on elytra and abdomen, and much larger paramere with distinctly deeper medioapical emargination.

Figures

Figure 30. Bisnius lubricus sp. nov. A, aedeagus, dorsal (parameral side) view; B, median lobe of aedeagus, lateral view; C, underside of paramere; D, sternite IX of male; E, sternite VIII of male; F, tergite X of male. Scale bars = 0.5 mm.