Belonuchus puncticulus Rougemont, 2004

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 : 2168-2170

Belonuchus puncticulus Rougemont, 2004

( Figure 8A,B )

Rougemont, 2004: 263 ( Belonuchus , type locality: Thailand: Doi Pui ) .

Examined material

Paratype: one male, China: Yunnan: Ruili , 4 February 1993, G. de Rougemont collected ( CRL) .

Description

Head and pronotum black, shining. Antennae black-brown with antennomeres I–II to various extent dark brown. Elytra black with posterior margin and suture markedly reddish-brown. Scutellum black. Abdomen black with feebly blue lustre. Mandibles, maxillary and labial palpi and legs dark brown.

Body depressed, 6.77 mm long (HPL: 1.96 mm). Head rounded quadrangular, 0.98 mm long, 0.90 mm wide, almost as long as wide (HW: HL = 0.92), slightly widened posteriad behind eyes, with broadly obtuse hind angles. Entire frons distinctly impressed, densely punctate, narrowly impunctate along midline, each side with 10–12 punctures. Tempora 0.41 mm long, sparsely and coarsely punctate; eyes small, slightly prominent, 0.25 mm long, 0.60 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, long waves. Antennae moderately long, antennomere I very long, thickened towards apex, antennomere III distinctly longer than antennomere II, antennomere IV slightly longer than wide, antennomeres V–VI almost as long as wide, antennomeres VII–X slightly transverse, antennomere XI distinctly longer than wide, obliquely truncate.

Pronotum distinctly narrowed posteriad, lateral margin distinctly concave in posterior half; 0.90 mm long, 0.73 mm wide, slightly wider than head (PW: HW = 0.82); 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 mm long, 1.22 mm wide, 1.27 times as long as pronotum, densely and finely punctate, punctures separated by one to two times their diameter. Scutellum large, triangular, densely and finely punctate.

Abdomen slightly narrowed posteriad, widest 1.14 mm, punctures separated by one to two 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 three 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. Genital segments with styli of tergite IX simple, moderately setose apically. Sternite IX with markedly asymmetrical proximal portion, apex slightly emarginate, each lobe bearing one moderately long apical seta. Tergite X simple, triangular, subtruncate at apex with numerous apical setae.

Aedeagus very characteristic, apical portion of median lobe narrowed to reverse triangular shape, with truncate apex ( Figure 8A ); in lateral view, apical portion with a small, dorso-lateral extension ( Figure 8B ); paramere small, bifurcate apically, branches widely separated at base, lacking sensory peg setae on underside of paramere.

Distribution

China (Yunnan), Thailand.

Remarks

Rougemont (2004) described Belonuchus puncticulus from China and Thailand. Belonuchus puncticulus and B. punctifrons ( Cameron, 1926) can be easily distinguished from the congeners by the impressed frons with dense punctures. Belonuchus puncticulus differs from B. punctifrons by smaller body, posterior margin and suture of elytra markedly reddish-brown (elytra entirely black in the latter species) and different morphology of aedeagus.

Figures

Figure 8. Belonuchus puncticulus Rougemont, 2004. (A) Aedeagus, ventral view; (B) median lobe of aedeagus, lateral view. Belonuchus punctifrons (Cameron, 1926). (C) aedeagus, ventral view; (D) median lobe of aedeagus, lateral view; (E) sternite VIII of male; (F) sternite VIII of female; (G) genital segment with styli of tergite IX; (H) sternite IX of male; (I) tergite X of male; (J) tergite X of female; (K) gonocoxites of female genital segment. Scale bars 0.5 mm.