Trisunius iaculatus, Assing, 2011

Assing, V., 2011, Trisunius gen. nov. from the southern East Palaearctic and the Oriental regions (Coleoptera: Staphylinidae: Paederinae: Medonina), Linzer biologische Beiträge 43 (1), pp. 195-220 : 207-208

Trisunius iaculatus nov.sp. ( Figs 34-40 )

T y p e m a t e r i a l: Holotype Ƌ: " China: Yunnan [CH07-30], Nujiang Lisu Aut. Pref., Nu Shan , 7 km NNW Coajian, 25°43'29''N, 99°07'57''E, 2420 m, second. pine forest with shrubs, litter, bark sifted, 11.VI.2007, M. Schülke / Holotypus Ƌ Trisunius iaculatus sp.n. det. V. Assing 2011" (cAss) . Paratypes: 4 exs.: same data as holotype (cSch) ; 6 exs.: " China: Yunnan [CH07-13], Baoshan Pref., Gaoligong Shan, E pass, 36 km SE Tengchong, 2200 m, 24°49'32''N, 98°46'06''E, decid. forest, litter, wood, fungi sifted, 31.V.2007, M. Schülke " (cSch, cAss); 1 ex.: same data, but "leg. A. Pütz " (cPüt); 8 exs. [2 teneral]: " China: Yunnan, Lincang Pref., Laobie Shan, Wei Bo Shan pass, 24°08'16''N, 99°42'53''E, 2375 m, creek valley, devastated second. decid. forest, litter & moss sifted, 8.IX.2009, leg. M. Schülke [CH09-35]" (cSch, cAss); 11 exs. [1 teneral]: " China: Yunnan, Lincang Pref., Wuliang Shan, old pass road, W side, 24°42'58.6''N, 10°29'52.0''E, 2200 m, small creek valley with primary forest remnant, litter & debris sifted, 12.IX.2009, leg. M. Schülke [CH09-47]" (cSch, cAss); 2 exs.: " China: Yunnan, Lincang Pref., Bangma Shan, E pass, 17 km NW Lincang, 23°57'31''N, 99°56'13''E, 2040 m, secondary pine forest, litter, dead wood & mushrooms sifted, 9.IX.2009, leg. M. Schülke [CH09-36]" (cSch, cAss); 12 exs. [teneral]: " China: Yunnan, Lincang Pref., Bangma Shan, 20 km NW Lincang, 2210 m, 23°58'25''N, 99°54'36''E, water reservoir, devast. forest with ferns, litter & ferns sifted, reservoir bank, 9.IX.2009, leg. M. Schülke [CH09-37]" (cSch, cAss); 1♀: " China: Yunnan, Pu'er Pref., Ailao Shan, 37 km NW Jingdong, 24°45'12''N, 100°41'24.5''E, 2300 m, devastated forest remnant, litter & dead wood sifted, 13.IX.2009, leg. M. Schülke [CH09-48]" (cSch); 3 exs. [1 teneral]: " China: Yunnan, Baoshan Pref., Gaoligong Shan, 78 km N Tengchong, 2000 m, 25°44'49''N, 98°33'29''E, cleft with creek and forest remnant, litter & dead wood sifted, 1.IX.2009, leg. M. Schülke [CH09-21]" (cSch, cAss); 2 exs.: " China: Yunnan, Lincang /Dali Pref., Wuliang Shan , old pass road, N pass, 24°45'16.4''N, 100°29'50.3''E, 2350 m, forest remnant & tea plantation litter, mushrooms, grass sifted, 16.IX.2009, leg. M. Schülke [CH09-55]" (cSch, cAss) .

D e s c r i p t i o n: Body length 3.0- 3.5 mm. Habitus as in Fig. 34 . Coloration variable: head (except for the yellowish to reddish-yellow frons) and pronotum reddish to dark-brown; elytra brown to dark-brown, usually at the suture and the humeral angles more or less extensively yellowish, occasionally of uniform coloration; abdomen blackish-brown; legs and antennae reddish.

Head ( Fig. 35 ) approximately as broad as long; punctation fine and moderately dense; interstices with distinct microsculpture. Eyes approximately half as long as postocular region in dorsal view, or slightly shorter. Anterior margin of labrum with two teeth on either side of median incision ( Fig. 36 ), external teeth sometimes very small.

Pronotum ( Fig. 35 ) approximately 1.05 times as long as wide and 0.90-0.95 times as wide as head; punctation less fine and more distinct than that of head; midline with narrow impunctate band; interstices with microsculpture at least in anterior, lateral, and posterior portions, median dorsal portion often without microsculpture.

Elytra 1.05-1.15 times as long as pronotum ( Fig. 35 ); humeral angles marked; punctation dense and shallow, less distinct than that of pronotum; interstices without microsculpture. Hind wings fully developed. Metatarsomere I approximately as long as II.

Abdomen slightly narrower than elytra, widest at segment VI; punctation fine and moderately dense; interstices with distinct microsculpture; posterior margin of tergite VII with palisade fringe.

Ƌ: sternite VII not distinctly modified ( Fig. 37 ); sternite VIII with small posterior excision ( Fig. 38 ); aedeagus approximately 0.45 mm long; ventral process of distinctive shape, in lateral view slender and apically very acute, in ventral view spear-shaped and apically acute ( Fig. 39-40 ).

E t y m o l o g y: The specific epithet is derived from the Latin noun iaculum (spear) and refers to the shape of the ventral process of the aedeagus in ventral view.

C o m p a r a t i v e n o t e s: This species is characterized particularly by the conspicuous shape of the aedeagus, as well as by the coloration of the elytra and the relatively long elytra.

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: The known distribution of T. iaculatus includes the Nu Shan, Gaoligong Shan, Laobie Shan, Wulian Shan, Bangma Shan, and Ailao Shan in western Yunnan, China. The type specimens were sifted from the leaf litter in various forest habitats at altitudes of 2000-2400 m in May, June, and September. Several specimens collected in September are teneral. Syntopic species are T. truncatus , T. spathulatus , and T. ligulatus .

Figures

Figs 34-40: Trisunius iaculatus nov.sp.: (34) habitus; (35) forebody; (36) labrum; (37) male sternite VII; (38) male sternite VIII; (39) aedeagus in lateral view; (40) ventral process of aedeagus in ventral view. Scale bars: 34: 1.0 mm; 35: 0.5 mm; 37-38: 0.2 mm; 36, 39-40: 0.1 mm.