Priochirus (Eutriacanthus) bipunctatus, Fauvel, 1895

Wu, Jie & Zhou, Hong-zhang, 2007, Taxonomy Of The Subgenus Eutriacanthus Jakobson, Of The Genus Priochirus Sharp, From Southern China, With The Description Of Two New Species From Guangxi And Yunnan (Coleoptera: Staphylinidae: Osoriinae), Raffles Bulletin of Zoology 55 (2), pp. 267-276 : 271-273

Priochirus (Eutriacanthus) bipunctatus, Fauvel, 1895

( Figs. 8–11 )

Leptochirus bipunctatus Fauvel, 1895: 180 (type locality: Bírmanie, Carin Cheba , 900–1,100 m; Carin Ghécu, 1,300–1,400 m; Tenasserim, mont Mooleyit, 1,800–1,900 m; Plapoo; Siam, monts de La Khone).

Priochirus bipunctatus Heller, 1898: 7 ; Bernhauer & Schubert, 1910: 15 (subgenus Triacanthus ); Cameron, 1930: 97 (subgenus Triacantochirus); Scheerpeltz, 1933: 1002; Greenslade, 1971: 138 (subgenus Eutriacanthus ); Herman, 2001: 1115.

Leptochirus nigrita Fauvel, 1902: 13 (variety of bipunctatus ; type locality: Malacca; Sumatra); Bernhauer & Schubert, 1910: 15; Herman, 2001: 1115 (synonym of bipunctatus ).

Material examined. – 2 males, 3 females, China, Guangxi, Napo , 960–1,005 m, 12 Apr.1998, Haisheng Zhou coll. ( IOZ-CAS) ; 1 male, 4 females, China, Yunnan, Xishuangbanna, Mengla , 730 m, 13 Feb.2004, Jie Wu coll. ( IOZ-CAS) ; 5 males, 7 females, China, Hainan, Wuzhi mountain , 820 m, 7 Jul.2004, Jie Wu and Yongjie Chen coll. ( IOZ-CAS) .

Redescription. – Body moderately depressed. Antennae reddish-brown; head dark red and shiny; pronotum and elytra red; femorae and tibiae dark red, tarsi slightly red-brown; abdomen black with posterior margin of each segment slightly red-brown.

Head transverse ( Fig. 8 ), parallel-sided, frontal angle weakly convex behind lateral teeth; frontal impression about twice as wide as median length, posterior margin obliquely convergent backwards forming a sharp angle; median tooth distinctly projecting and pointed, slightly longer than 2 lateral teeth, distinctly contracted behind apex, base strongly convex along central disc of frontal impression; lateral teeth pointed, apex slightly curved inwards, lateral face with 5 or 6 setae turning upward, medially with row of long setae extending onto anterior margin; median sulcus deep, not anteriorly connected with frontal impression, gradually broadened backwards, posterior end about twice as wide as middle width of median longitudinal sulcus on pronotum; vertex smooth and shiny, some scattered punctures and setae along lateral and postero-lateral margins, posterior margin near to posterior end of sulcus with indistinct fovea bearing 3 or 4 setae; clypeus short and declivous anteriorly, slightly convex in middle, anterior margin almost truncate. Eyes glabrous and distinctly convex, longitudinal diameter about 1/2 length of head.

Mandible similar to that of P. (E.) pulchellus , but with relatively denser setae occurring along lateral margin. Mentum trapeziform and setose, anterior margin truncate, median tooth small and pointed, lateral margin moderately convex, with two waved and rugose transverse ridges ( Fig. 11 ).

Antennae almost reaching shoulder of elytra posteriorly; 1st segment baculiform, emarginate at apex; 2nd segment smallest and transverse; 3rd segment elongate and narrowed at base, about 1.5 times as long as 2nd; 4–6th segments longer than wide; 7–10th segments gradually transverse; 11th segment slightly elongate, apically rounded, about 1.8 times as long as 10th.

Pronotum wider than long, anterior margin weakly bisinuate, sides parallel, posterior margin slightly protruding backwards in middle; surface smooth with sparse micropunctures, near to lateral region with fine vermiform sculptures; median longitudinal sulcus deep, widest in middle, not reaching both anterior and posterior margins; disc on each side of sulcus with big puncture; along marginal area with some scattered, coarse, setiferous punctures, especially denser at anterior and posterior angle; lateral line complete on posterior margin of pronotum and reaching basal line. Mesoscutellum tongueshaped, smooth and shiny.

Protibiae laterally with 13–16 denticles, which gradually becoming shorter basally, on dorsal side with distinct spine closely behind apical spur. Middle and hind tibiae densely setose.

Elytra slightly wider than long, humeri rounded, almost parallel-sided, weakly convex in posterior 1/4, combined posterior margins distinctly emarginate; surface with sparse micropunctuations; along base and sides with moderately dense setae of various length.

Abdomen cylindrical, broadened posteriorly and widest at 7th segment; all segments, except 8th, narrowed at base; surface with sparse setae, mostly long and erect, relatively denser at

lateral sides; punctures small, especially denser in basal half of tergites, gradually becoming sparser posteriorly.

Male: Aedeagus similar to that of P. (E.) pulchellus , but parameres rounded at apex, not pointed ( Figs. 9, 10 ).

Measurements. – Body length: 13.0–15.0 mm. HL: 0.62 mm; HW: 3.47 mm; PL: 1.56 mm; PW: 2.13 mm; EL: 2.08 mm; EW: 2.16 mm (n = 3).

Remarks. – In coloration, this species is similar to P. (E.) apicalis Eppelsheim, 1895, but with a black abdomen, not reddish as in the latter. Furthermore, the median tooth in this species is distinctly contracted behind the apex, not stout as in P. (E.) apicalis. This species is widely distributed in Southeast Asia and is recorded from southern China for the first time.

Distribution. – China (Guangxi, Hainan, Yunnan); India, Myanmar, Thailand and Indonesia.

Figures

Figs. 8–11. Priochirus (Eutriacanthus) bipunctatus (Fauvel, 1895): 8, head and pronotum, dorsal view; 9, aedeagus, dorsal view; 10, aedeagus, lateral view; 11, mentum. Scale bars: (Fig. 8) = 1.00 mm; (Figs. 9–11) = 0.25 mm.