Atheta (Microdota) amischoides, Assing, 2009

Assing, V., 2009, New species and additional records of Homalotini, Athetini, Pygostenini, and Lomechusini from Yunnan, China (Coleoptera: Staphylinidae: Aleocharinae), Linzer biologische Beiträge 41 (1), pp. 485-507 : 498-501

Atheta (Microdota) amischoides nov.sp. ( Figs 42-47 )

Holotype Ƌ: China: Yunnan [ CH 07-35], Dali Bai Aut. Pref., Wuliang Shan, 9 km SW Weishan, 2450-2500 m, 25°10'14"N, 100°14'22"E, W slope, oaks and pines, sifted, 13. VI.2007, leg. A. Pütz / Holotypus Ƌ Atheta amischoides sp.n. det. V. Assing 2007 (cAss). Paratypes: 3ƋƋ: same data as holotype (cPüt, cAss).

D e s c r i p t i o n: 2.0- 2.3 mm. Habitus as in Fig. 42 . Coloration: head, abdominal segments V-VI, and anterior half of segment VII dark-brown to blackish-brown; pronotum, elytra, abdominal segments III-IV, and posterior half of segment VII paler brown; segment VIII dark-yellowish; legs yellowish; antennae dark-brown, with antennomeres I- II reddish-brown.

Head somewhat wedge-shaped, i. e., distinctly dilated behind eyes and weakly transverse, approximately 1.1 times as wide as long ( Fig. 43 ); punctation rather sparse and extremely fine, barely noticeable; surface with shallow, but distinct microreticulation and with moderate shine. Eyes composed of numerous ommatidia, weakly projecting from lateral contours of head and slightly shorter than postocular region in dorsal view. Antennae gradually and distinctly incrassate apically; antennomere IV weakly transverse; X almost twice as wide as long.

Pronotum approximately 1.20 times as wide as long and 1.20 times as wide as head; maximal width in anterior half; posterior angles moderately marked ( Fig. 43 ); punctation similar to that of head; microsculpture slightly more distinct than that of head; pubescence of midline directed cephalad.

Elytra approximately 1.2 times as wide and at suture approximately 0.8 times as long as pronotum; punctation dense and fine, but more distinct than that of pronotum ( Fig. 44 ); microsculpture present. Hind wings apparently present, but possibly of reduced length. Metatarsomere I approximately as long as II.

Abdomen approximately as wide as elytra, widest at segments V-VI; tergites III-V anteriorly with shallow impression; punctation fine, moderately dense on tergite III, decreasing in density from tergites IV-VI, and very sparse on tergites VI-VIII; microsculpture shallow, but distinct; posterior margin of tergite VII with palisade fringe.

Ƌ: tergite VIII posteriorly broadly convex, not crenulate ( Fig. 44 ); posterior margin of sternite VIII broadly convex and narrowly membranous ( Fig. 45 ); median lobe of aedeagus of distinctive shape and with characteristic internal structures ( Figs 46-47 ).

♀: unknown.

E t y m o l o g y: The name (adjective) refers to the resemblance of this species, especially regarding its head shape, to some species of the genus Amischa THOMSON.

C o m p a r a t i v e n o t e s: From all its consubgeners known from China, this species is separated especially by the distinctive morphology of the aedeagus and additionally as follows:

from A. alternantoides PACE (Yunnan) , whose male sexual characters are unknown, by much shorter and more slender elytra;

from A. chinamicula PACE (Zhejiang) by larger size, different head shape, and a posteriorly non-crenulate male tergite VIII;

from A. elytralis PACE (Zhejiang) by much shorter elytra;

from A. formosanorum PACE ( Taiwan, Hongkong) by darker coloration and larger size;

from A. gibba PACE (Sichuan) by distinctly shorter and more slender elytra, and by the smoothly convex posterior margin of the male tergite VIII;

from A. gonggaensis PACE (Sichuan) by different head shape, as well as by much shorter and more slender elytra;

from A hailuogouensis PACE (Sichuan) by smaller size and darker coloration;

from A. hongkongiphila PACE ( Hongkong) by different head shape, much smaller eyes, and narrower elytra;

from A. ipercristata PACE (Gansu) by much shorter and more slender elytra, and by the completely different shape of the male tergite VIII;

from A. jiensis PACE (Beijing) by more slender body and different head shape;

from A. laminarum PACE (Yunnan) by different head shape, smaller eyes, and much shorter setae (legs, forebody);

from A. lanzhouensis PACE (Gansu) by a less slender body, different head shape, and the smoothly convex posterior margin of the male tergite VIII;

from A. masculifrons PACE (Yunnan) by the completely different shape of the male tergite VIII;

from A. miriapex PACE (Sichuan) by larger eyes and darker coloration;

from A. permixta PACE (Gansu) , A. pseudovagans PACE ( Hongkong) , A. persimplex PACE ( Hongkong) , and A. kadooriaorum PACE ( Hongkong) by much smaller eyes and different head shape;

from A. liaoningensis PACE (Liaoning) , A. marcopoloi PACE (Xinjiang) , A. mon PACE (Honkong) , A. nanior PACE (Yunnan) , A. philamicula PACE (Sichuan) , A. ponderata PACE (Yunnan) (male sexual characters unknown), A. tang PACE (Sichuan) , A. tardoides PACE (Yunnan) (male sexual characters unknown), A. iperintroflexa PACE (Beijing) (male sexual characters unknown), and A. sichuanicola PACE (Sichuan) by different head shape and much shorter and more slender elytra, from the latter also by much smaller eyes;

from A. neoamicula PACE (Sichuan) , whose male sexual characters are unknown, by different head shape, more slender body, and more slender elytra;

from A. ocularis CAMERON ( Hongkong) by much smaller eyes, different head shape, the the posterior not dentate male tergite VIII;

from A. taichungensis PACE (Taiwan) by darker coloration of the antennal base and by much shallower microsculpture of the head and pronotum;

from A. taiwanensis PACE (Taiwan) by much darker antennae, larger eyes, and distinctly longer elytra;

from A. tricoloroides PACE (Zhejiang) by darker coloration, different head shape, and shorter elytra;

from A. yanensis PACE (Beijing) by uniformly yellowish legs and different head shape;

from A. zhongianensis PACE (Yunnan), whose male sexual characters are unknown, by the absence of impressions on the head and pronotum, as well as by the narrower and uniformly brownish elytra;

from A. xueica ASSING (Yunnan) , A. foliacea ASSING (Yunnan) , A. dimorpha ASSING (Yunnan) , A. detruncata ASSING (Yunnan) , A. hastata ASSING (Yunnan) , A. geostiboides ASSING (Yunnan) , A. elisa ASSING (Shaanxi) , and A. puetzi PACE (Shaanxi) by larger eyes, longer elytra, and (fully?) developed hind wings.

For illustrations of the sexual characters of the above species see PACE (1992a, 1993, 1995, 1998c, 1999b, 2004b) and ASSING (2002, 2004a, 2006a).

D i s t r i b u t i o n a n d b i o n o m i c s: The type locality is situated in the Wuliang Shan, to the southwest of Weishan in Yunnan province. The specimens were sifted from the litter of oak and pine at an altitude of approximately 2500 m.

Figures

Figs 42-47: Atheta amischoides nov.sp.: (42) habitus; (43) forebody; (44) male tergite VIII; (45) male sternite VIII; (46-47) median lobe of aedeagus in lateral and in ventral view. Scale bars: 42: 1.0 mm; 43: 0.5 mm; 44-45: 0.2 mm; 46-47: 0.1 mm.