Leptusa (Drepanoleptusa) emeiana, Assing, 2021

Assing, Volker, 2021, New species and additional records of Leptusa from the Palaearctic region, with a focus on the faunas of China and the Caucasus region (Coleoptera: Staphylinidae: Aleocharinae), Beiträge Zur Entomologie = Contributions to Entomology 71 (1), pp. 103-126 : 118-119

Leptusa (Drepanoleptusa) emeiana spec. nov.

urn:lsid:zoobank.org:act:43EA4727-AFD3-4C04-826C-73ADCE6DAEF0

( Figs 5 , 51–55)

Type material: Holotype : “ CHINA, Sichuan, Emei Shan, N29°32'48.4", E103°20'06.3", 2342 m, 17.vi.2010, sifting36, V. Grebennikov / Holotypus  Leptusa emeiana sp. n. det. V. Assing 2020” ( CAS) . Paratypes: 3 exs.: same data as holotype ( CNC, cAss) ; 2 exs.: “P. R. CHINA, Sichuan, Emei Shan, N 29°33.6' E 103°20.6', 27.vi.–5.vii.2009, 1800–2400 m, siftings11–17 V. Grebennikov ” ( CNC, cAss) ; 1 ex.: “P. R. CHINA, Sichuan, Emei Shan, N29°30'46.5", E103°19'57.0", 14.vi.2010, 3035 m, sifting28, V. Grebennikov ” ( CNC) ; 2 exs.: “P. R. CHINA, Sichuan, Emei Shan, N29°30'54.2", E103°19'50.6", 14.vi.2010, 3055 m, sifting29, V. Grebennikov ” (cAss) ; 2 exs.: “P. R. CHINA, Sichuan, Emei Shan, N29°32'37.3", E103°19'57.5", 18.vi.2010, 2440 m, sifting37, V. Grebennikov ” ( CNC) ; 1 ex.: “P. R. CHINA, Sichuan, Emei Shan, N29°33'51", E103°20'47", 23.v.2011, 1779 m, sift03, V. Grebennikov” ( CNC); 2 , 1  [most likely mislabeled]: “P. R. CHINA, Yunnan, E slope Cangshan at Dali, N25°40'13.2", E100°07'54.8", 13.v.2010, 2728 m, sifting08, V. Grebennikov” ( CAS, CNC, cAss) .

Comment: The description was originally based only on the three specimens bearing labels indicating they were collected in Cang Shan. They were studied nearly ten years ago. Since the species was at that time assumed to be endemic to the Cang (Diancang) Shan, the specific epithet cangica, an adjective derived from the name of the mountain, was chosen, and one of the three specimens was designated as the holotype and labeled accordingly (“ Holotypus  Leptusa cangica sp. n. det. V. Assing 2012”). When the material from several localities in Emei Shan was made available only several years later, it appeared very likely that the specimens bearing labels indicating that they were collected in Diancang were in fact mislabeled. Identical confusion was observed for Silusa edentula ASSING , in press, and a reverse confusion seems to be true of Leptusa auriculata (see the section on that species).

Etymology: The specific epithet (adjective) is derived from the name of the mountain range where this species was first discovered.

Description: Body length 1.9–2.2 mm. Habitus as in Fig. 5 . Colouration: body reddish, with abdominal segment VI and anterior portion of segment VII infuscate; legs and antennae pale-reddish.

Head weakly transverse; punctation dense and shallow; interstices narrower than diameter of punctures, with very shallow microsculpture and glossy; eyes weakly convex and small, little more than half as long as postocular region in lateral view, approximately as large as antennomere I in cross-section. Antennae gradually and moderately incrassate apically, preapical antennomeres approximately twice as wide as long.

Pronotum 1.25–1.30 times as wide as long and 1.20– 1.25 times as wide as head; maximal width in anterior half; posterior angles obtusely marked; punctation finer and less defined than that of head; microsculpture pronounced.

Elytra approximately 0.7 times as long as, and noticeably narrower than pronotum; punctation dense, much coarser than that of pronotum. Hind wings completely reduced.

Abdomen distinctly broader than elytra; punctation fine and not very dense; interstices with shallow microsculpture; posterior margin of tergite VII without palisade fringe.

: tergite VII with or without minute median tubercle posteriorly; tergite VIII with truncate and somewhat serrate posterior margin (Fig. 54); sternite VIII (Fig. 55) obtusely angled posteriorly and with fringe of long thin marginal setae; median lobe of aedeagus 0.32–0.33 mm long, shaped as in Figs 51–52; apical lobe of paramere short, abruptly narrowed apically (Fig. 53).

: tergite VIII of similar shape as in male; sternite VIII convex posteriorly; spermatheca not distinctive.

Comparative notes: The median lobe of the aedeagus somewhat resembles that of L. discolor , from which the new species is distinguished by numerous characters, particularly its smaller and relatively broader body, shorter antennae, a finer punctation of the forebody, a relatively broader pronotum, a less parallel and broader abdomen with much finer and sparser punctation, and by the different male sexual characters (much shorter and smaller tubercle on the male tergite VII, differently shaped male and female tergites and sternites VIII, different shape of the median lobe of the aedeagus). For illustrations of L. discolor see ASSING (2006 b).

Distribution and natural history: According to the labels, the type material was sifted in one locality in Diancang (Cang) Shan (Yunnan) and several localities in Emei Shan (Sichuan). This suggests that this small and micropterous species is remarkably widespread, provided that the specimens from Yunnan were not mislabeled; they were collected by V. Grebennikov only a month before some of the paratypes from Emei Shan. Therefore, the presence of this species is Diancang should be considered doubtful for the time being (see also the distribution section of L. auriculata above). The altitudes range from 1780 to 3055 m.

Figures

Figs 1–8: Male habitusof Leptusaspp.1 – L.excisa; 2 – L.grandipennis; 3– L.auriculata; 4– L.gonggana; 5– L.emeiana; 6 – L. jizuica;