Orphnebius (Deroleptus) elevatus, Assing, 2019

Assing, Volker, 2019, On the Lomechusini fauna of the Palaearctic and Oriental regions. XXVI. New species, a new synonymy, and additional records (Coleoptera: Staphylinidae: Aleocharinae), Beiträge Zur Entomologie = Contributions to Entomology 69 (1), pp. 33-70 : 51-52

Orphnebius (Deroleptus) elevatus spec. nov.

urn:lsid:zoobank.org:act:839D7EBF-6AD4-420B-97A1-8448D1F5036B

( Figs 12–15 , 16, 33, 109)

Type material: Holotype: “ LAOS, Khammouane prov., Nakai env., 14–18.iv.2017, 17°34'N, 105°10'E, 500 m, A. & R. Hergovits lgt. / Holotypus Orphnebius elevatus sp. n., det. V. Assing 2017” ( MMB).

Etymology: The specific epithet is the past participle of the Latin verb elevare and alludes to the presence of long elevations on either side of the elytral suture.

Description: Body length 4.8 mm; length of forebody 2.0 mm. Coloration ( Figs 12–13 , 16, 33): head blackish-brown; pronotum reddish; elytra reddish with the postero-lateral portions slightly and diffusely darker; abdomen reddish with segment VII blackish-brown; legs yellowish-red; antennae reddish; maxillary palpi yellowish with palpomere III slightly darker.

Head ( Figs 12–13 ) nearly 1.5 times as broad as long, posterior angles obsolete; clypeus not membranous, truncate anteriorly; dorsal surface with sparse and fine punctation, median dorsal portion extensively impunctate; interstices without microsculpture. Eyes large and bulging, nearly reaching posterior margin of head. Antenna (Fig. 33) not particularly slender, 1.4 mm long; antennomeres III slender, IV approximately as long as broad, V–X weakly transverse, only slightly increasing in width, X much less than 1.5 times as broad as long, and XI approximately as long as the combined length of IX and X.

Pronotum ( Figs 12–13 ) of transversely trapezoid shape, broadest anteriorly, approximately 1.5 times as broad as long and approximately 0.9 times as broad as head; disc rather strongly convex in cross-section; lateral margins straight in dorsal view, converging posteriad; punctation extremely fine and sparse, midline broadly impunctate.

Elytra ( Figs 12–13 ) approximately 1.2 times as long as, and distinctly broader than pronotum; on either side of suture with an oblong elevation; punctation fine and rather sparse; interstices without microsculpture and very glossy. Hind wings fully developed. Legs long and slender; metatibia approximately 1.0 mm long; metatarsus nearly as long as metatibia; metatarsomere I slightly longer than the combined length of II and III.

Abdomen (Fig. 16) gradually tapering from base to apex; sternite IV and paratergites IV each with a horizontal postero-lateral extension, the sternal and the paratergal extension contiguous ( Fig. 14 ); tergites III– VI practically impunctate, except for a pair of tubercles near posterior margin of tergite VI each bearing a long dark seta; tergite VII ( Fig. 15 ) with dense and extensive non-setiferous punctation, these punctures separated by longitudinal ridges anteriorly, near posterior margin with approximately 10 small setiferous tubercles, posterior margin with palisade fringe; tergite VIII ( Fig. 15 ) in posterior portion with dark setae inserting in distinct tubercles, posterior margin strongly concave and with pronounced tubercles rendering the margin serrate.

: unknown.

: sternite VIII with convex posterior margin; spermatheca (Fig. 109) of distinctive shape.

Comparative notes: Like O. globifer , O. elevatus belongs to the O. siwalikensis group. In coloration, habitus, and the modifications of the abdominal segment IV, O. elevatus is most similar to O. baccillatus ASSING, 2016 , whose original description is based on a unique female holotype from Laos. The new species is distinguished from O. baccillatus by shorter and more slender (i.e., finer) antennae, smaller body size ( O. baccillatus : body length 6.2 mm; length of forebody 2.5 mm), the presence of elevations on either side of the elytral suture, the shorter extension of sternite IV, the longer extension of paratergites IV (in relation to the extension of sternite IV), the pair of setiferous tubercles near the posterior margin of tergite VI, the more strongly concave posterior margin of tergite VIII, and above all by the completely different shape of the spermatheca. For illustrations of O. baccillatus and numerous other species of the O. siwalikensis group see ASSING (2016b).

Distribution and natural history: The type locality is situated in Khammouane province, Laos, at an altitude of 500 m. Additional data are not available.

Figures

Figs 1–15:Myrmoecia urartu (1), Pella feldmanni (2), Orphnebius taurus (3–5), O. fortesetosus (6–7), O. morulus (8–9), O. globifer (10–11), andO. elevatus (12–15): habitus (1–3); head and pronotum (4–5); forebody (6, 8, 10, 12–13); abdomen (7, 9, 11); anterolateral portion of abdomen (14); tergites VII–VIII (15). Scale bars: 1–3: 1.0 mm; 4–15: 0.5 mm.