Nazeris semifissus, 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 : 367-368

Nazeris semifissus sp. n.

( Figs 40–45 , Map 3 )

Type material: Holotype ♂: “ CHINA [22a] – Yunnan, SE Pingbian, primary forest, 22°54'31"N, 103°41'44"E, 2100 m, 28.VIII.2014, V. Assing / Holotypus ♂ Nazeris semifissus sp. n., det. V. Assing 2014” (cAss).

Paratypes: 1 ♂, 2 ♀♀: same data as holotype (cAss) ; 4 ♂♂: same data as holotype, but leg. M. Schülke (cSch, cAss) ; 1 ♂: “ CHINA [22] – Yunnan, SE Pingbian, primary forest, 22°54'31"N, 103°41'44"E, 2100 m, 27.VIII.2014, V. Assing” (cAss) .

Etymology: The specific epithet (Latin, adjective: halfdivided) alludes to the conspicuously long and narrow posterior incision of the male sternite VIII.

Description: Species of moderate size; body length 5.0– 6.2 mm; length of forebody 2.8–3.1 mm. Coloration: head dark-reddish to dark-brown; pronotum dark-brown to blackish-brown; elytra dark-reddish to reddish-brown; abdominal segments III–VI dark-reddish to reddishbrown, segment VII dark-brown to blackish with narrowly reddish posterior margin, and segments VIII–X reddish-yellow with the posterior portion of tergite VIII more or less distinctly and more or less extensively infuscate ( Fig. 41 ); legs and antennae yellowish, with antennomere I slightly darker.

Head ( Fig. 40 ) moderately oblong, 1.06–1.08 times as long as broad, disc with moderately pronounced and rather extensive median elevation; lateral contours behind eyes smoothly and weakly curving towards posterior constriction in dorsal view, posterior angles obsolete; punctation very dense, rather coarse, weakly confluent in places, and distinctly umbilicate; interstices forming narrow ridges, without microsculpture. Eyes approximately one-third as long as distance from posterior margin of eye to posterior constriction in dorsal view, or slightly longer. Antenna approximately 1.9 mm long, rather long in relation to body size.

Pronotum ( Fig. 40 ) rather weakly oblong, 1.15–1.18 times as long as broad and 0.90–0.95 times as broad as head; punctation dense and much coarser than that of head; midline with more or less pronounced impunctate glossy elevation in posterior half; lateral portions with uneven surface, with irregular longitudinal glossy callosities; interstices without microsculpture and glossy.

Elytra ( Fig. 40 ) approximately 0.53 times as long as pronotum; humeral angles obsolete; dorsal surface more or less extensively depressed or impressed anteriorly; punctation defined and rather coarse, but distinctly less coarse than that of pronotum; interstices without microsculpture and glossy. Hind wings completely reduced. Metatarsomere I much shorter than the combined length of II–V.

Abdomen approximately 1.25 times as broad as elytra; punctation coarse and dense on tergites III–V, less dense and finer on tergite VI, and rather sparse and fine on tergites VII and VIII; interstices without microreticula- tion; posterior margin of tergite VII without palisade fringe; posterior margin of tergite VIII strongly convex ( Fig. 41 ).

♂: sternite VII ( Fig. 42 ) strongly transverse, approximately 1.55 times as broad as long, with shallow postero-median impression with sparse long and dark setae obliquely directed postero-mediad, posterior margin with conspicuously large concavity, this concavity with a pair of dense clusters of long black setae in the middle and with a sparser row of very long black setae laterally; sternite VIII ( Fig. 43 ) indistinctly transverse, posterior excision conspicuously narrow and deep, approximately half as deep as length of sternite; aedeagus ( Figs 44–45 ) approximately 0.95 mm long; ventral process of oblong triangular shape and apically acute, subapically with a small ventral tooth (best visible in lateral view); dorso-lateral apophyses long and straight, extending somewhat beyond apex of ventral process, and apically moderately dilated.

Comparative notes: Nazeris semifissus is well-characterized by the conspicuous modifications of the male sternite VII, the remarkably deep and narrow posterior incision of the male sternite VIII, and by the morphology of the aedeagus. Similar apomorphies were not found in any other species recorded from Yunnan and adjacent regions (Guangxi and Guizhou provinces; North Vietnam).

Distribution and natural history: The type locality is situated in the Dawei Shan Virgin Forest Park near Pingbian in southeastern Yunnan ( Map 3 ) and identical to that of N. discissus . The specimens were sifted from leaf litter in a primary subtropical broad-leaved forest at an altitude of 2100 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.