Domene immarginata, Assing & Feldmann, 2014

Assing, V. & Feldmann, B., 2014, On Domene scabripennis ROUGEMONT and its close relatives (Coleoptera: Staphylinidae: Paederinae), Linzer biologische Beiträge 46 (1), pp. 499-514 : 505-509

Domene immarginata nov.sp.

( Figs 18-26 , 35 , 44 , Map 1 )

Type material Holotype: " 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] / Holotypus Domene immarginata sp.n., det. V. Assing 2013" ( cAss). Paratypes [see also Addendum]: 1, 3 [3 teneral]: same data as holotype ( cSch); 2 [1 slightly teneral], 1: " CHINA: Yunnan, Lincang Pref., Bang-ma Shan , 33 km SSW Lincang, 2150 m, 23°35'41''N, 100°00'27''E, decid. forest remnant, N-slope, litter and dead wood sifted, 11.IX.2009, leg. M. Schülke [CH09-42]" ( cSch, cAss); 2 [1 teneral]: same data, but leg. Wrase ( cSch); 1, 1: " CHINA: Yunnan, Lincang Pref., Xue Shan, 48 km N Lincang, 2070 m, 24°19'03''N, 100°07'13''E, forest remnant, N-slope, litter & mushrooms sifted, 12.IX.2009, leg. M. Schülke [CH09-45]" ( cSch, cFel); 1: " CHINA: Yunnan, Baoshan Pref., Gaoligong Shan, W pass 35 km SE Tengchong, 2100 m, 24°50'18''N, 98°45'43''E, devast. prim. dec. forest, litter, wood, mushrooms sifted, 25.VIII.2009, leg. M. Schülke [CH09-06]" ( cAss); 1: " CHINA: Yunnan, Baoshan Pref., Gaoligong Shan, 33 km SE Tengchong, 2150 m, 24°51'22''N, 98°45'36''E, devast. primery [sic] deciduous forest, litter, wood, mushrooms sifted, 28.VIII.2009, leg. M. Schülke [CH09-08a]" ( cAss).

Etymology: The specific epithet is composed of the Latin prefix im- and the past participle of the Latin verb marginare (to seam, to border); it alludes to the absence of a palisade fringe at the posterior margin of the abdominal tergite VII.

Description: Body length 9.0-11.0 mm; length of forebody 5.2-6.2 mm. Habitus as in Fig. 18 . Coloration: body blackish; legs brown, with the profemora and the apical halves of the meso- and metafemora blackish-brown to blackish; antennae dark-brown, with antennomere I usually somewhat darker.

Head ( Fig. 19 ) 1.00-1.03 times as long as broad, widest behind eyes; punctation ( Fig. 20 ) moderately coarse, distinctly umbilicate, and very dense, interstices forming narrow ridges. Antenna 3.9-4.0 mm long; antennomere X nearly twice as long as broad.

Pronotum ( Fig. 19 ) approximately 1.2 times as long as broad and 1.06-1.08 times as broad as head, widest at anterior angles and distinctly tapering posteriad; lateral margins convex in dorsal view; punctation ( Fig. 21 ) similar to that of head or slightly coarser; midline with or without narrow rudiments of a glossy line.

Elytra ( Fig. 19 ) approximately 0.75 times as long as pronotum, each elytron with 2-3 more or less distinct and more or less irregular longitudinal narrowly elevated ridges; disc often more or less distinctly impressed; suture elevated in posterior two thirds; macropunctation ( Fig. 22 ) coarse, irregular, partly confluent, and partly somewhat seriate; interstices with irregular micropunctation, otherwise not microsculptured. Hind wings reduced. Protarsomeres I-IV rather weakly dilated in both sexes.

Abdomen approximately as broad as elytra; punctation extremely fine and dense on tergites III-VI, even finer, but somewhat less dense on tergite VIII; interstices with distinct microreticulation; posterior margin of tergite VII without palisade fringe; tergite VIII with convex posterior margin.

: sternite VII ( Fig. 23 ) with unmodified pubescence; sternite VIII ( Fig. 24 ) with narrow and shallow postero-median impression, this impression with few scattered modified, rather short and stout black setae, on either side of posterior excision with cluster of short dark setae; aedeagus ( Figs 25-26 ) approximately 1.15 mm long; ventral process very slender and distinctly curved in lateral view; dorsal plate lamellate and moderately sclerotized, with long apical and very short, weakly sclerotized basal portion.

: tergites IX-X and sternite VIII as in Figs 35 , 44.

Comparative notes: As can be inferred from the similar external morphology (especially the sculpture of the elytra) and particularly from the similar modifications of the male sternite VIII (distinct cluster of modified setae on either side of the posterior excision) and the similarly derived morphology of the aedeagus (ventral process very slender), D. immarginata is most closely related to the species pair D. scabripennis + D. alesiana , from which it differs by the shape of the head (widest behind eyes), the less coarse punctation of head and pronotum, the more oblong and more slender (in relation to head) pronotum, the absence of a palisade fringe at the posterior margin of the abdominal tergite VII, the shape and chaetotaxy of the male sternite VIII (with more distinct median depression with modified pubescence; shape of posterior excision), as well as by the shape of the ventral process and by the absence of sclerotized spines in the internal sac of the aedeagus. It additionally differs from D. scabripennis by the distinctly darker coloration of the legs.

Distribution and natural history: Thedistributionisconfinedto several localities in the Bangma Shan, the Xue Shan (to the north of Lincang), and the Gaoligong Shan in western Yunnan, China ( Map 1 ). The specimens were sifted from forest leaf litter at altitudes of 2070-2210 m. Some of them are more or less distinctly teneral.

Figures

Map 1: Distributions of the species of the Domene scabripennis group: D. immarginata (white circles), D. sagittata (black diamond), D. scabripennis (black triangle), D. alesiana (white triangle), and D. firmicornis (black circle).

Figs 18-26: Domene immarginata nov.sp.: (18) habitus; (19) forebody; (20) median dorsal portion of head; (21) median portion of pronotum; (22) anterior sutural portion of elytra; (23) male sternite VII; (24) male sternite VIII; (25) aedeagus in lateral view; (26) apical portion of aedeagus in ventral view. Scale bars: 18-19: 1.0 mm; 23-26: 0.5 mm; 20-22: 0.2 mm.

Figs 27-35: Domene sagittata nov.sp. (27-34) and D. immarginata nov.sp. (35): (27) habitus; (28) forebody; (29) median dorsal portion of head; (30) sutural portion of elytra; (31) male sternite VII; (32) male sternite VIII; (33) aedeagus in lateral view; (34) apical portion of aedeagus in ventral view; (35) female tergites IX-X. Scale bars: 27-28: 1.0 mm; 31-35: 0.5 mm; 29-30: 0.2 mm.

Figs 36-44: Domene firmicornis nov.sp. (36-43) and D. immarginata nov.sp. (44): (36) forebody; (37) median portion of head; (38) median portion of pronotum; (39) disc of left elytron; (40) male sternite VII; (41) male sternite VIII; (42) aedeagus in lateral view; (43) apical portion of aedeagus in ventral view; (44) female sternite VIII. Scale bars: 36: 1.0 mm; 40-44: 0.5 mm; 37-39: 0.2 mm.