Orphnebius serratus spec. nov.

(Figs 7, 32, 39, 236–243)

Type material: Holotype ♂: “ Laos-N (Louangphrabang), 11.–21.v.2002, 19°35'N, 101°58'E, Thong Khan, ~ 750 m, Vít Kubáň leg. / Holotypus ♂ Orphnebius serratus sp. n., det. V. Assing 2015” (NHMB) .

Paratypes: 19 exs. [2 teneral]: same data as holotype (NHMB, cAss); 1 ♀: “ Laos, Phongsaly prov., Phongsaly env., 6.–17.v.2004, ~ 1500 m, 21°41'N 102°06–8'E, V. Kubáň leg.” (NHMB); 1 ♀: “ Lao, Phongsaly prov., 21°41–2''N 102°06–8'E, 28.v.–20.vi.2003, Phongsaly env., ~ 1500 m, Vít Kubáň leg.” (cAss); 1 ♂ [teneral]: “ Laos, Phongsaly prov., 21°21'N 102°03'E, Ban Sano Mai, 19.–26.v.2004, ~ 1150 m, Vít Kubáň leg.” (NHMB) 1 ♂ [teneral]: “ Laos-N (Oudomxai), 1–9.v.2002, ~ 1100 m, 20°45'N 102°09'E, Oudom Xai (17 km NEE), Vít Kubáň leg.” (NHMB) .

Etymology: The specific epithet (Latin, adjective) alludes to the serrate posterior margin of the abdominal tergite VIII.

Description: Body length 3.0–5.0 mm; length of forebody 1.5–2.1 mm. Coloration: forebody black; abdomen red; legs with the femora and tibiae blackish-brown, and with the tarsi reddish; antennae blackish with antennomeres II–IV at least partly dark-reddish; maxillary palpi brown with the apical palpomere yellowish.

Head (Fig. 32) of transversely rectangular shape, approximately 1.5 times as broad as long (length measured from sclerotized portion of clypeus); posterior angles nearly obsolete; posterior margin truncate or weakly convex; clypeus extensively membranous; dorsal surface nearly impunctate. Eyes large, more than twice as long as postocular region in dorsal view. Antenna (Fig. 7) 1.0– 1.2 mm long; antennomere I very short, barely as long as the combined length of antennomeres II and III; antennomere IV weakly transverse and flattened; antennomere V much broader than antennomere IV; antennomeres V–X distinctly asymmetric, moderately flattened, and strongly transverse, more than twice as broad as long, and gradually increasing in width; XI short, only slightly longer than the combined length of IX and X.

Pronotum (Fig. 32) approximately 1.3 times as broad as long and 1.06–1.10 times as broad as head, moderately convex in cross-section; lateral and posterior margins together nearly forming a semi-circle, posterior angles completely obsolete; disc with a median pair of punctures, otherwise practically impunctate; lateral margins with three long, erect, stout black setae.

Elytra (Fig. 32) 0.75–0.80 times as long as pronotum; punctation sparse and fine; pubescence long, fine, pale, and sub-erect or depressed. Hind wings fully developed. Protibia moderately to distinctly dilated, more so in larger than in smaller specimens (Fig. 39). Metatarsomere I slightly shorter than the combined length of II and III.

Abdomen: tergites III–VI with a lateral setiferous puncture on either side, VI with four additional punctures at posterior margin; tergite VII with dense non-setiferous punctures in posterior two-thirds, posterior margin with palisade fringe; tergite VIII (Fig. 240) with a curved transverse series of eight setiferous tubercles bearing long black setae in posterior portion, with a lateral cluster of fine setae on either side, posterior margin convex and with eight short teeth; sternite VIII with broadly convex posterior margin.

♂: segments IX–X distinctly modified ( O. hauseri type), with dense and long pubescence; median lobe of aedeagus (Figs 236–238) approximately 0.83 mm long; ventral process short, bifid, both apices incised in the middle; paramere (Fig. 239) approximately 0.7 mm long, with slender condylite; paramerite of distinctive shape, external margin notched at apical two-fifths.

♀: segments IX–X distinctly modified (modifications of the O. hauseri type), with dense and long pubescence; proximal portion of spermathecal capsule simply curved, near distal portion distinctly dilated (Figs 241–243).

Comparative notes: Orphnebius serratus is distinguished from other species of the O. serratus subgroup by the dilated protibiae, by the distinctive shapes of the median lobe and the parameres of the aedeagus, and by the shape of the spermatheca.

Distribution and natural history: The specimens were collected in five localities in Louangphrabang, Phongsaly, and Oudomxai provinces, North Laos, at altitudes between 750 and 1500 m, together with numerous other Orphnebius species.