Quedius (Microsaurus) arcus, Cai & Zhao & Zhou, 2015

Quedius (Microsaurus) arcus View in CoL sp. nov.

( Figs. 5, 5-1 View FIGURE 5 )

Type material. Holotype ♂, CHINA: Ningxia Province: Jingyuan County, Liupan Mountain, Erlong River Forest Farm , 2000 m, 23. VI. 2008, coll. Haisheng Zhou and Zongyi Zhao. Paratypes: CHINA: Ningxia Province: 1 ♀, Jingyuan County, Liupan Mountain, Erlong River Forest Farm, 2000 m, 21. VI. 2008, coll. Haisheng Zhou and Zongyi Zhao ; 4 ♂♂, 5 ♀♀, Jingyuan County, Liupan Mountain, Erlong River Forest Farm, 2050 m, 22. VI. 2008, coll. Haisheng Zhou and Zongyi Zhao ; 6 ♂♂, Jingyuan County, Liupan Mountain, Erlong River Forest Farm, 2000 m, 23. VI. 2008, coll. Haisheng Zhou and Zongyi Zhao ; 1 ♂♂, Jingyuan County, Liupan Mountain, Longtan Forest Farm, 1950 m, 23. VI. 2008, coll. Haisheng Zhou and Zongyi Zhao ; 1 ♂, Jingyuan County, Liupan Mountain, Xixia Forest Farm, 2100 m, 25. VI. 2008, coll. Haisheng Zhou and Zongyi Zhao ; 1 ♂, 4 ♀♀, Jingyuan County, Liupan Mountain, Xixia Forest Farm, 2200 m, 27. VI. 2008, coll. Haisheng Zhou and Zongyi Zhao ; 3 ♂♂, 1 ♀, Jingyuan County, Liupan Mountain, Fengtai Forest Farm, 2300 m, 3. VII. 2008, coll. Haisheng Zhou and Zongyi Zhao ; 1 ♀, Jingyuan County, Liupan Mountain, Dongshanpo Forest Farm, 2200 m, 6. VII. 2008, coll. Haisheng Zhou and Zongyi Zhao.

Description. Head black; pronotum, scutellum and elytra blackish brown; abdomen blackish brown, each tergite with posterior margin slightly paler; antennae dark reddish brown, labrum dark brown, mandibles dark reddish brown, maxillary and labial palpi dark brown; legs blackish brown.

BL = 11.9 mm, BW = 2.0 mm, MHWL = 5.6 mm, FHWL = 5.5 mm, HL/PL/EL/MHWL/FHWL = 1.00: 1.33: 1.50: 4.48: 4.45, HW/PW/EW/AW = 1.00: 1.36: 1.51: 1.61

Head ( Fig. 5A View FIGURE 5 ) round, about as long as wide, HW/HL = 1.05; eye moderately large and slightly convex, in dorsal view tempora shorter than length of eye, gradually narrowed posteriad, HEL/HTL = 1.67; posterior frontal setiferous puncture situated behind level of posteriomedial margin of eye, separated by distance about twice as long as diameter of puncture; one smaller setiferous puncture between it and temporal setiferous puncture at posterior margin of eye; temporal setiferous puncture situated slightly closer to nuchal constriction of head than to posterior margin of eye, with several small setiferous punctures arranged in an oblique curve behind it; two basal setiferous punctures situated closer to nuchal constriction than to posterior frontal setiferous puncture; head with fine and dense microsculpture of transverse waves and irregular meshes. Antenna moderately long with segment I longer than segment II or III, segment III distinctly longer than segment II, segments IV–VII, XI slightly longer than wide, segments VIII–X slightly wider than long.

Pronotum ( Fig. 5B View FIGURE 5 ) slightly wider than long, PW/PL = 1.08, slightly narrowed anteriad, lateral margins not explanate, posterior margin broadly rounded, posterior angle vaguely visible; three setiferous punctures in each dorsal and sublateral row, last sublateral row puncture situated behind level of large lateral setiferous puncture; surface of pronotum with very fine and dense microsculpture of transverse waves.

Scutellum ( Fig. 5C View FIGURE 5 ) with very fine and dense microsculpture of transverse waves, impunctate.

Elytra ( Fig. 5C View FIGURE 5 ) moderately long, slightly wider than long, EW/EL = 1.06, ESL/EL = 0.56, slightly broadened posteriad, surface of each elytron covered with dense and coarse setiferous punctures, transverse interspaces between punctures nearly equal to diameter of puncture, surface between punctures without microsculpture.

Abdominal tergite II impunctate; setiferous punctures of other tergites slightly finer and denser than those of elytra, almost evenly distributed on each tergite, and generally becoming sparser toward apex of abdomen; tergite VII with whitish apical seam of palisade setae.

Male first four segments of fore tarsus strongly dilated, sub-bilobed, each heavily covered with modified pale setae ventrally, segment II about as wide as apex of tibia; tergite VIII with basal ridge complete and nearly straight, with two long setae on each side; sternite VIII ( Fig. 5-1A View FIGURE 5 ) with basal ridge complete, slightly arched backward in middle, with four long setae on each side, apical margin with a shallow and moderately wide medioapical emargination, a small triangular area in front of the emargination impunctate; sternite IX ( Fig. 5-1B View FIGURE 5 ) with basal portion long and curved, with apex almost truncate; tergite X ( Fig. 5-1C View FIGURE 5 ) with basal side broadly and shallowly concave, apical margin slightly protruded and rounded; aedeagus in lateral view ( Fig. 5-1F View FIGURE 5 ) with apex of paramere almost reaching that of median lobe, median lobe with a small hook-shaped process at apex and a strong conspicuous longitudinal ridge along midline below apex, both pointing toward paramere side; aedeagus in parameral view ( Fig. 5-1G View FIGURE 5 ) with paramere a little narrower than median lobe even at its widest point, slightly asymmetrical, apex with small medioapical emargination, hook-shaped process of median lobe fitting into this emargination, median lobe wide at base, gradually constricted at about basal 2/3, apical 1/3 dilated laterally and narrowed into acute apex ( Figs. 5E, F, 5-1D View FIGURE 5 ). apical portion of paramere with two long apical setae at each side of apical emargination, and two subapical setae on each lateral side below apex, underside with 5 sensory peg setae arranged in cluster near apex at each side of apical emargination ( Figs. 5D, 5-1E View FIGURE 5 ).

Female first four segments of fore tarsus similar to those of male, but less dilated, segment II distinctly narrower than apex of tibia; tergite VIII with basal ridge complete, nearly straight, with one long seta on each side; sternite VIII with basal ridge complete, nearly straight, with three long setae on each side; tergite X ( Fig. 5-1H View FIGURE 5 ) with basal side broadly and shallowly concave, with a distinct subtriangular area in middle more strongly sclerotized and pigmented, apical margin protruded and pointed.

Hind wings. Male and female with hind wings monomorphic. Both male and female with hind wings fully developed, BL/MHWL/FHWL = 1.00: 0.47: 0.47; MHWL/FHWL = 1.01.

Distribution. China (Ningxia).

Diagnosis. This new species belongs to the lineage comprised of Q. arcus sp. nov., Q. bernhauerianus Korge , Q. subwrasei sp. nov. and Q. wrasei Smetana within euryalus group. They share the character combination: relatively large body size (>= 9.5 mm), dark body color (blackish brown to black), relatively smaller and less convex eyes, asymmetrical apical portion of male sternite IX, slightly asymmetrical paramere of aedeagus and inverted Y-shaped process at apex of median lobe. However, it can be easily distinguished from others by having apical portion of male sternite IX less distinctly asymmetrical and the conspicuous ridge below apex of median lobe.

Etymology. The specific name is from the Latin noun arcus (a bow) in apposition, referring to the broadly rounded posterior margin of pronotum.