Anaulacaspis beijingensis
Creators: name: Assing, Volker
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Staphylinidae
Anaulacaspis
Anaulacaspis beijingensis

description: Anaulacaspis beijingensis (PACE, 1998)
(Figs 173–177, Map 7)
Melagria beijingensis PACE, 1998: 398.
Melagria marginata PACE, 1998: 400; syn. n.
Type material examined: M. beijingensis: Holotype ♂: “ CHINA Beijing, B.N.U at light, V–VI.1993, G. de Rougemont / Holotypus Melagria beijingensis, det. R. Pace 1995 / Melagria beijingensis sp. n., det. R. Pace 1995 / Anaulacaspis beijingensis (Pace), det. V. Assing 2016” (MHNG). M. marginata: Holotype ♀: “ CHINA Beijing, Panshan, 8.v.1995, G. de Rougemont / Holotypus Melagria marginata, det. R. Pace 95 / Melagria marginata sp. n., det. R. Pace 1995 / Anaulacaspis beijingensis (Pace), det. V. Assing 2016” (MHNG).
Comment: The original description of A. beijingensis is based on a male holotype from “ China, Beijing, B.N.U., at light” and two female paratypes from “ China Yingtaogou” (PACE 1998), that of M. marginata on a unique female holotype from “ China, Beijing, Panshan” (PACE 1998). According to PACE (1998), A. marginata is distinguished from A. beijingensis by completely brown antennae (A. beijingensis: antennomeres I–II yellowishbrown), distinctly transverse antennomeres IX and X, parallel temples, a distinctly transverse pronotum, the coloration of the elytra (yellowish coloration extending anteriad along suture), and by the less strongly sclerotized and shorter distal portion of the spermathecal capsule. An examination of the holotypes of A. beijingensis and A. marginata, as well as of additional material from Shaanxi, whose aedeagus is identical to that illustrated by PACE (1998) for A. beijingensis, revealed pronounced intraspecific variation regarding all these characters, but no significant differences. Consequently, there is little doubt that the holotype of A. marginata is conspecific with that of A. beijingensis. Both names were made available in the same article. Anaulacaspis beijingensis is designated as the senior synonym, since this name is represented by a male type specimen.
Additional material examined: China: Shaanxi: 7 ♂♂, 4 ♀♀, 15 km N Xi’an, road to Xi’an airport, bank of Wei He river, 34°24'N, 108°55'E, 400 m, 22.VIII.1995, leg. Wrase & Schülke (MNB, cAss).
Redescription: Body length 1.8–2.2 mm; length of forebody 0.9–1.0 mm. Coloration: head, pronotum, and abdomen blackish-brown to blackish; elytra dark-brown to blackish-brown, posterior margin and sometimes also the sutural portion more or less extensively yellowish; legs dark-yellowish to yellowish-brown; antennae dark-brown to blackish brown, with the basal 2–3 antennomeres often more or less distinctly paler.
Head approximately 1.15 times as broad as long, with more or less pronounced sexual dimorphism; punctation fine and dense in both sexes. Eyes longer than postocular region in dorsal view. Antenna 0.7–0.8 mm long and with sexual dimorphism.
Pronotum 1.10–1.15 times as broad as long and approximately as broad as head, with pronounced sexual dimorphism.
Elytra approximately as long as, or slightly shorter than, pronotum; punctation dense and fine. Hind wings present.
Abdomen approximately as broad as elytra; punctation dense and distinct; interstices without appreciable microsculpture; tergite VIII (Fig. 173) strongly transverse and with truncate posterior margin, marginal setae moderately long and unmodified.
♂: head flattened or more or less extensively and more or less distinctly impressed; antenna approximately 0.8 mm long, antennomeres IV weakly oblong, V approximately as broad as long, and VI–X of gradually increasing width and increasingly transverse, X approximately 1.5 times as broad as long; pronotum with extensive median impression and with dense and distinct punctation; sternite VIII (Fig. 174) with strongly convex posterior margin, marginal setae fine and rather short; median lobe of aedeagus (Figs 175–176) approximately 0.33 mm long; ventral process apically very acute both in lateral and in ventral view.
♀: head neither flattened nor impressed; antenna approximately 0.7 mm long, antennomeres IV approximately as broad as long, V–X of gradually increasing width and increasingly transverse (more so than in male), X nearly twice as broad as long; pronotum without distinct median impression and with fine punctation; sternite VIII (Fig. 177) strongly transverse, posterior margin broadly concave in the middle and with moderately long and fine marginal setae.
Comparative notes: Based on the morphology of the aedeagus, the pronounced sexual dimorphism of the pronotum, as well as on the shapes of tergite VIII and sternite VIII, A. beijingensis belongs to the A. naevula group. Among the species of this group it is characterized particularly by the sexual dimorphism of the antennae (unique), the coloration, the shape and chaetotaxy of tergite VIII, and the conspicuously acute apex of the ventral process of the aedeagus.
Distribution and natural history: Anaulacaspsis beijingensis has been recorded only from Beijing and Shaanxi provinces, China (Map 7). The additional material was collected on a river bank at an altitude of 400 m.
description: Published as part of Assing, Volker, 2016, Revision of the Anaulacaspis species of the Palaearctic region (Coleoptera: Staphylinidae: Aleocharinae), pp. 201-255 in Beiträge Zur Entomologie = Contributions to Entomology 66 (2) on pages 244-245, DOI: 10.21248/contrib.entomol.66.2.201-255, http://zenodo.org/record/5212606