Sphaerobulbus biplagiatus, Smetana, Aleš, 2006

Smetana, Aleš, 2006, Contributions to the knowledge of the “ Staphylinus­complex ” (Coleoptera: Staphylinidae: Staphylinini) of China. Part 13. The genus Sphaerobulbus Smetana 2003. Section 3, Zootaxa 1317, pp. 41-47 : 43-45

Sphaerobulbus biplagiatus spec. nov.

( Figs. 1–5 )

Type material. Holotype (male): CHINA: Yunnan: “ CHINA, W Yunnan Dequen, 15– 18.7. 2002 Lgt. E. Kučera” (ASC).

Description. Black, fore body rather dull; visible abdominal tergites 4 and 5 each with patch of golden tomentose pubescence in middle; maxillary and labial palpi piceous, antennae black, becoming vaguely paler toward apex, legs black with vaguely paler tarsi, front tarsi brownish. Head of rounded quadrangular shape, with entirely rounded posterior angles, wider than long (ratio 1.27), eyes small, slightly convex, tempora considerably longer than eyes from above (ratio 2.1), dorsal surface of head densely and finely punctate and pubescent, punctation gradually becoming less dense anteromediad; interspaces between punctures with dense, semimeshed microsculpture. Antenna moderately long, segment 3 slightly longer than segment 2 (ratio 1.18), segments 4 to 8 longer than wide, becoming gradually shorter, segments 9 and 10 about as long as wide, last segment shorter than two preceding segments combined. Pronotum slightly longer than wide (ratio 1.09), slightly narrowed anteriad, narrow marginal groove disappearing downwards at about anterior third of pronotal length; disc of pronotum with complete, indistinct, impunctate midline, dilated in front of posterior margin into slightly shiny (due to rudimentary microsculpture) mirror; punctation and pubescence similar to that on head, gradually becoming somewhat sparser mediad, interspaces between punctures with microsculpture similar to that on head. Scutellum sparsely, finely punctate and setose, surface rather shiny, with extremely fine, rudimentary microsculpture mediobasally. Elytra short, somewhat widened posteriad, base distinctly depressed, at suture considerably (ratio 0.66) at sides distinctly (ratio 0.82) shorter than pronotum at midline; punctation fine and dense, finely asperate, interspaces between punctures with fine, dense, granulose microsculpture, elytra therefore appearing dull; pubescence piceous­black, dense. Wings each reduced to minute, nonfunctional stump. Abdomen with fifth visible tergite lacking pale apical seam of palisade setae; tergite 2 (in front of first visible tergite) entirely, finely and densely punctate and pubescent; posterior basal line on first three visible abdominal tergites simple, almost straight; all tergites very finely and very densely punctate, punctation finer than that on elytra, evenly covering each tergite and in general becoming hardly sparser toward apex of abdomen; interspaces with very fine, rudimentary meshed microsculpture that becomes almost obsolete toward middle of each tergite; pubescence black, dense.

Male. Sternite 8 with moderately wide and deep, obtusely triangular medioapical emargination. Male genital segment with sternite 9 with rather deep and wide apical emargination ( Fig.1 ). Tergite 10 as in Fig. 2 , moderately large, with arcuate apex bearing long apical setae, otherwise moderately densely setose. Aedoeagus as in Figs. 3–5 ; median lobe with subparallel­sided middle portion, with rather short, triangular apical portion with acute apex; paramere situated on median lobe asymmetrically, with arcuate apex not quite reaching apex of median lobe; underside of paramere without black sensory peg setae; with two subapical setae at right margin, and with three curved spine­like setae ( Fig 5 ).

Female. Unknown.

Length 14.0 mm (abdomen slightly extended).

Geographgical distribution. Sphaerobulbus biplagiatus is at present known only from the type locality in northern Yunnan.

Bionomics. Nothing is known about the habitat requirements of this species

Recognition and comments. Sphaerobulbus biplagiatus shares the character state of a patch of golden tomentose pubescence in the middle of the visible abdominal tergites 4 and 5 with two species, but it differs from them by other morphological characters, as well as geographically. It is most similar to S. brezinai Smetana, 2003 , but the latter species is larger with longer antennae and not quite as short elytra, and the aedoeagus is shaped differently (see Figs. 32–34 in Smetana, 2003); in addition, S. brezinai is endemic to Yulongshan. The other species, S. businskorum Smetana, 2005 , is on average considerably larger (14.0–19.0 mm) with forebody distinctly shinier (due to the lack of microsculpture on interspaces between punctures on head and pronotum), with scutellum finely and densely punctate and setose, and with the differently shaped aedoeagus (see Figs. 15–17 in Smetana, 2005b); in addition, S. businskorum is at present known only from the high elevations of mountain ranges of Daxue Shan and Shalui Shan in west­central Sichuan.

Etymology. The specific epithet is a combination of the Latin adverb bis (twice) and the Latin adjective plagiatus, ­ a, ­ um (crooked, marked). It refers to the presence of the pair of yellow tomentose spots on abdominal tergites.

Figures

FIGURES 1 – 11. Details of Sphaerobulbus biplagiatus (1 – 5) and S. ornatus (6 – 11). 1, 6 — sternite 9 of male genital segment; 2, 7 — tergite 10 of male genital segment; 3, 8 — aedoeagus, ventral view; 4, 9 — apical portion of median lobe, ventral view, paramere removed; 5, 10 — underside of apical portion of paramere; 11 — tergite 10 of female genital segment.