Belonuchus applanatus, Li & Zhou, 2010

Li, Liang & Zhou, Hong-Zhang, 2010, Revision of the Chinese species of the genus Belonuchus Nordmann (Coleoptera: Staphylinidae: Philonthina), Journal of Natural History 44 (35 - 36), pp. 2149-2177 : 2155-2157

Belonuchus applanatus sp. nov.

( Figure 3A–G )

Type material

Holotype: male, China: Yunnan: Xishuangbanna: Menla , 940 m, 19 February 2004, Wu Jie and Lu Yongping collected (IZ-CAS) . Paratypes: 22 males, 34 females, same data as holotype (IZ-CAS) .

Description

Head and pronotum black, shining. Antennae black-brown with antennomeres I–III to various extent reddish-brown or dark brown. Elytra black-brown or dark brown with posterior margin and suture sometimes reddish-brown. Scutellum black. Abdomen black with feebly blue lustre, posterior margins of tergites III–VII narrowly reddishbrown; tergite VIII sometimes entirely reddish-brown. Mandibles, maxillary and labial palpi and legs reddish-brown.

Body depressed, 6.20–7.34 mm long (HPL: 1.88–2.04 mm). Head rounded quadrangular, 0.81–1.06 mm long, 0.90–0.98 mm wide, almost as long as wide (HW: HL = 0.92–1.10), slightly widened posteriad behind eyes, with broadly obtuse hind angles. Frons with four large punctures more or less placed as a transverse row. Tempora 0.41–0.49 mm long, sparsely and coarsely punctate; eyes moderately large, slightly prominent, 0.25–0.33 mm long, 0.60–0.80 times as long as tempora. Lateral portions of head with scattered, large setiferous punctures; vertex largely impunctate. Dorsal surface of head with distinct and profound microsculpture of oblique waves. Antennae short, antennomere I very long, thickened towards apex, antennomere III slightly longer than antennomere II, antennomere IV almost as long as wide, antennomeres V–X distinctly transverse, antennomere XI almost as long as wide, obliquely truncate.

Pronotum distinctly narrowed posteriad, lateral margin slightly concave in posterior half; 0.90–0.98 mm long, 0.73–0.81 mm wide, slightly narrower than head (PW: HW = 0.81–0.91); dorsal rows on pronotum each with four large punctures, sublateral rows each with two large punctures; dorsal surface with distinct and profound microsculpture of transverse waves.

Elytra slightly widened posteriad, 1.14–1.22 mm long, 1.14–1.22 mm wide, 1.16–1.27 times as long as pronotum, densely and finely punctate, punctures separated by two to three times their diameter. Scutellum large, triangular, densely and finely punctate.

Abdomen slightly narrowed posteriad, widest 0.98–1.06 mm, punctures separated by two to three times their diameter at base, gradually becoming sparser toward apex of each tergite; surface between punctures with exceedingly fine and dense microsculpture of transverse striae; first four visible abdominal tergites with two basal lines, elevated area between basal lines almost impunctate.

Male. Anterior tarsomeres I–IV simple, not dilated, without modified pale setae ventrally. Sternite VIII with inconspicuous medio-apical emargination ( Figure 3F ). Genital segments with styli of tergite IX simple, moderately setose apically. Sternite IX with markedly asymmetrical proximal portion, slightly emarginate apically ( Figure 3E ). Tergite X simple, triangular, widely emarginate at apex with two long apical setae ( Figure 3C ).

Aedeagus slender ( Figure 3A–G ); median lobe with apical portion evenly, narrowed into subacute apex; in lateral view, apical portion slightly bent dorsad; paramere small, divided into two short widely separated branches, lacking sensory peg setae on underside of paramere.

Female. Anterior tarsomeres I–IV similar to that of male. Sternite VIII rounded at apex, without medio-apical emargination ( Figure 3G ). Genital segments with styli of tergite IX similar to that of male. Tergite X triangular, subtruncate at apex, with numerous apical setae ( Figure 3D ).

Etymology

The specific epithet is derived from Latin word applanatus (meaning “depressed”) and refers to the depressed body form.

Distribution

At present known only from China (Yunnan).

Remarks

The new species is similar to Belonuchus tripunctatus Fauvel, 1895 (NHML), but can be easily distinguished from the latter by distinctly smaller body size and sparser punctures on tempora and abdominal tergites.

Figures

Figure 3. Belonuchus applanatus sp. nov. (A) Aedeagus, ventral view; (B) median lobe of aedeagus, lateral view; (C) tergite X of male; (D) tergite X of female; (E) sternite IX of male; (F) sternite VIII of male; (G) sternite VIII of female. Scale bars 0.5 mm.