Orsunius wunderlei, Assing, 2011

Assing, V., 2011, Orsunius gen. nov. from the Oriental region (Coleoptera: Staphylinidae: Paederinae: Medonina), Linzer biologische Beiträge 43 (1), pp. 221-244 : 224-226

Orsunius wunderlei nov.sp. ( Figs 1-14 )

T y p e m a t e r i a l: Holotype Ƌ: " Thailand, Chiang Mai, Doi Inthanon, Doi Pui, 1100- 1500 m, 10.XI.1995, P. Wunderle / Holotypus Ƌ Orsunius wunderlei sp.n. det. V. Assing 2011" (cAss). Paratypes: 43 exs.: same data as holotype (cWun, cAss, cFel, cSch, OÖLL).

D e s c r i p t i o n: Body length 4.0-5.0 mm. Habitus as in Fig. 1 . Coloration: head and pronotum reddish; elytra reddish-yellow to reddish, with the anterior half often slightly and diffusely darker; abdomen reddish to dark-reddish, with the apical portions of segments VII and VIII yellowish; legs and antennae yellowish.

Head of transversely rectangular shape, 1.20-1.25 times as broad as long ( Fig. 2 ); posterior margin distinctly concave in the middle; punctation coarse and dense ( Fig. 3 ); posterior median portion of dorsal surface with small area without, or with sparse punctation; interstices glossy, in most of dorsal surface distinctly narrower than diameter of punctures, reduced to narrow ridges; sides with relatively few long dark-brown setae. Eyes large, slightly longer than postocular portion in dorsal view. Antennae slender ( Fig. 4 ); preapical antennomeres approximately as wide as long. Ventral aspect of head with microsculpture; gular sutures anteriorly separated by a distance of approximately the width of antennomere III. Mouthparts as in Figs 5-8 , 12-13 .

Pronotum approximately 1.2 times as wide as long and 1.05-1.10 times as broad as head ( Fig. 2 ); posterior angles rounded, weakly marked; lateral margins visible only in posterior two thirds when viewed from above; lateral and anterior margins with rather few and not particularly long brownish setae; punctation slightly less coarse and less dense than that of head ( Fig. 9 ); midline broadly impunctate.

Elytra approximately 1.1 times as long as pronotum ( Fig. 2 ); punctation very dense and fine; interstices without microsculpture. Hind wings fully developed. Protarsomeres I-IV strongly dilated ( Fig. 1 ). Metatarsomere I longer than II and slightly shorter than the combined length of II and III.

Abdomen narrower than elytra; punctation extremely fine and dense, slightly less dense on posterior tergites; interstices with distinct microsculpture composed of isodiametric and short transverse meshes; posterior margin of tergite VII with palisade fringe.

Ƌ: sternite VII not distinctly modified; sternite VIII with truncate posterior margin ( Fig.

14); aedeagus approximately 0.9 mm long; ventral process large, laterally compressed, somewhat asymmetric in ventral view, and with apex of distinctive shape ( Figs 10-11 ).

C o m m e n t: The possibility that the absence of long black setae on the head, pronotum, and the elytra is an artefact resulting from post-mortem treatment of the material cannot be ruled out with certainty.

E t y m o l o g y: The species is named after my dear friend and colleague Paul Wunderle, who collected the types of this species, as well as those of O. prolongatus .

C o m p a r a t i v e n o t e s: This species is characterized particularly by the morphology of the aedeagus. For characters separating it from the similar and evidently closely related O. yunnanus see the following section.

D i s t r i b u t i o n a n d n a t u r a l h i s t o r y: Thetypelocalityissituatedin the Doi Inthanon, approximately 50 km to the southwest of Chiang Mai, northern Thailand. The specimens were sifted from a ditch with deep and moist leaf litter mixed with dead wood at an altitude of 1100-1500 m in November (WUNDERLE pers. comm.).

Figures

Figs 1-11: Orsunius wunderlei nov.sp.: (1) habitus; (2) forebody; (3) median dorsal portion of head; (4) antenna; (5) labrum; (6) maxilla; (7) labial palpus; (8) ligula; (9) median dorsal portion of pronotum; (10) aedeagus in lateral view; (11) apical portion of aedeagus in ventral view. Scale bars: 1: 1.0 mm; 2, 4: 0.5 mm; 3, 9-11: 0.2 mm; 5-8: 0.1 mm.

Figs 12-19: Orsunius wunderlei nov.sp. (12-14) and O. yunnanus nov.sp. (15-19): (12) left mandible; (13) right mandible; (14, 17) male sternite VIII; (15) habitus; (16) forebody; (18) aedeagus in lateral view; (19) apical portion of ventral process in lateral view. Scale bars: 15: 1.0 mm; 16: 0.5 mm; 12-14, 17-19: 0.2 mm.