Nazeris lamellatus, Assing, 2014

Assing, Volker, 2014, A revision of Nazeris. VI. On the fauna of East Yunnan, China (Coleoptera: Staphylinidae: Paederinae), Beiträge Zur Entomologie = Contributions to Entomology 64 (2), pp. 355-373 : 365-367

Nazeris lamellatus sp. n.

( Figs 34–39 , Map 3 )

Type material: Holotype ♂: “ CHINA [21] – Yunnan, NNE Pingbian , broad-leaved for., 23°00'39"N, 103°42'10"E, 1500 m, 26.VIII.2014, V. Assing / Holotypus ♂ Nazeris lamellatus sp. n., det. V. Assing 2014” (cAss).

Paratype ♂: same data as holotype (cAss) .

Description: Slender species of moderate size; body length 6.7–7.0 mm; length of forebody 3.5–3.6 mm. Coloration: body black; legs and antennae yellowish, with antennomere I slightly darker.

Head ( Fig. 34 ) moderately oblong, 1.06–1.07 times as long as broad, with moderately pronounced median elevation; lateral contours behind eyes smoothly curving towards posterior constriction in dorsal view, posterior angles obsolete; punctation very dense, rather coarse, rather shallow, partly confluent, and distinctly umbilicate; interstices forming narrow ridges, without microsculpture. Eyes slightly more than one-third as long as distance from posterior margin of eye to posterior constriction in dorsal view. Antenna approximately 2.0 mm long.

Pronotum ( Fig. 34 ) slender, approximately 1.25 times as long as broad and 0.9 times as broad as head; punctation very dense and much coarser than that of head; midline with narrow and rather long impunctate glossy elevation; lateral portions with uneven surface, with weakly pronounced longitudinal elevations without punctures; interstices without microsculpture and glossy.

Etymology: The specific epithet (Latin, adjective) alludes to the semi-membranous, very weakly sclerotized ventral process of the aedeagus.

Elytra ( Fig. 34 ) approximately 0.55 times as long as pronotum; humeral angles obsolete; dorsal surface depressed; punctation somewhat irregular and weakly defined, less coarse than that of pronotum; interstices with- out microsculpture and glossy. Hind wings completely reduced. Metatarsomere I elongated, nearly as long as the combined length of II–V.

Abdomen approximately 1.2 times as broad as elytra; punctation coarse and dense on tergites III–VI, slightly less dense and finer on tergite VII; interstices without microreticulation; posterior margin of tergite VII without narrow rudiment of a palisade fringe; posterior margin of tergite VIII strongly convex.

♂: sternite VII ( Fig. 35 ) moderately transverse, approximately 1.35 times as broad as long, posterior margin with a conspicuous median concavity; sternite VIII ( Fig. 36 ) weakly transverse, approximately 1.05 times as broad as long, posterior excision very narrowly V-shaped and approximately one-third as deep as length of sternite; aedeagus ( Figs 37–38 ) approximately 0.85 mm long; ventral process very weakly sclerotized and with semimembranous ventral and lateral portions; dorso-lateral apophyses ( Fig. 39 ) weakly sclerotized, apically slightly dilated, and short, approximately half as long as ventral process.

Comparative notes: Nazeris lamellatus is distinguished from all other congeners recorded from Yunnan by the completely different shape of the male sternite VII and the completely different morphology of the aedeagus, from most other species known from eastern Yunnan also by the median elevation, by the callosities and irregularly spaced punctation of the lateral portions of the pronotum, by the distinctly depressed elytra with somewhat irregular punctation, and by the shape of the posterior excision of the male sternite VIII. Among the described species of Nazeris , N. lamellatus may be most closely related to N. odzisan WATANABE, 1996 from North Vietnam, as can be inferred from the similar shape of the male sternite VIII (deep and narrow posterior excision), the presence of a posterior median concavity of the male sternite VII, and from the similar general morphology (shape of ventral process; short dorso-lateral apophyses) of the aedeagus. Based on the illustrations provided with the original description of N. odzisan , N. lamellatus differs from this species by the shape and chaetotaxy of the male sternite VII ( N. odzisan : posterior concavity very small; sternite with long and pronounced median impression, this impression without pubescence), by the different contours (both in lateral and in ventral view) of the ventral process of the aedeagus, and by the even shorter and apically more distinctly dilated dorsolateral apophyses. For illustrations of N. odzisan see WATANABE (1996).

Distribution and natural history: The type locality is situated to the north-northeast of Pingbian, in the periphery of the Dawei Shan Virgin Forest Park in southeastern Yunnan ( Map 3 ). The specimens were sifted from litter in a subtropical broad-leaved forest at an altitude of 1500 m.

Figures

Map 3: Distribution of Nazeris species in eastern Yunnan (N. zhangi lineage: black symbols): N. clavilobatus sp. n. (black circle); N. conicus sp. n. (black square); N. bulbosus sp. n. (black diamond); N. zhangi WATANABE & XIAO (black triangle), N. fibulatus sp. n. (white circle); N. lamellatus sp. n. (white diamond); N. semifissus sp. n. (white triangle).

Figs 34–45: Nazeris lamellatus sp. n. (34–39) and N. semifissus sp. n. (40–45): forebody (34, 40); male sternite VII (35, 42); male sternite VIII (36, 43); aedeagus in lateral and in ventral view (37–38, 44–45); left dorso-lateral apophysis (39); tergite VIII (41). Scale bars: 34, 40: 1.0 mm; 35–38, 41–45: 0.5 mm; 39: 0.1 mm.