Queskallion saetosum, Cai & Li & Zhou, 2020

Cai, Yanpeng, Li, Xiaoyan & Zhou, Hongzhang, 2020, A new species of Queskallion Smetana, 2015 (Coleoptera, Staphylinidae, Quediina) from China, ZooKeys 945, pp. 153-161 : 153

Queskallion saetosum sp. nov. Figures 1 , 2

Material examined.

Holotype: China • ♂; Sichuan Province, Baoxing County, Longdong, Ruobigou; alt. 1600 m; 10 August 2003; Xiaodong Yu (IZ-CAS) leg. Paratypes: 3 ♂♂, 1 ♀; same locality as holotype; 10-13 August 2003; Xiaodong Yu (IZ-CAS) leg.

Diagnosis.

This new species is very similar to Q. tangi Smetana in all characters, but it can be distinguished from the latter by having the male paramere of the aedeagus slightly narrower than the median lobe, underside with sensory peg setae arranged into one characteristic inversed Y-shaped figure, female tergite X with apical margin forming distinctive M-shaped indention; whereas the latter has male paramere of aedeagus with subapical portion slightly dilated laterally becoming wider than median lobe, underside with sensory peg setae arranged into two S-like figures, female tergite X with apical margin deeply and arcuately emarginated.

Description.

Head dark brown to blackish brown; pronotum, scutellum and elytra dark brown; abdomen dark brown, each tergite with posterior margin slightly paler; head, pronotum and abdomen strongly iridescent; antennae dark brown, labrum yellowish-brown, mandibles dark brown, maxillary and labial palpi dark brown; legs dark brown.

BL = 8.5 mm, BW = 1.7 mm, HL/PL/EL = 1.00: 1.52: 1.80, HW/PW/EW/AW = 1.00: 1.60: 1.84: 1.55.

Head (Fig. 1A ) obtusely quadrangular, nearly as wide as long, HW/HL = 1.05; eye moderately large and slightly convex, in dorsal view tempora shorter than length of eye, gradually narrowed posteriad, HEL/HTL = 1.50; no additional setiferous punctures between anterior frontal setiferous punctures; posterior frontal setiferous puncture situated distinctly behind level of posteriomedial margin of eye, about midway between posteriomedial margin of eye and nuchal constriction of head; temporal setiferous puncture situated closer to posterior margin of eye than to nuchal constriction, with some small setiferous punctures behind and below it; one basal setiferous puncture situated closer to nuchal constriction than to posterior frontal setiferous puncture; head with very fine and dense microsculpture of transverse waves and meshes. Antenna moderately long, with segment I longer than segment II or III, segment III longer than segment II, segments IV-XI slightly longer than wide.

Pronotum (Fig. 1B ) large and broad, wider than long, PW/PL = 1.10, distinctly narrowed anteriad, posteriolateral and posterior margins continuously and broadly rounded, lateral margins not explanate; three setiferous punctures in each dorsal and sublateral row, one additional setiferous puncture situated between each dorsal and sublateral row, distinctly behind level of last dorsal and sublateral row puncture, last sublateral row puncture situated behind level of large lateral setiferous puncture; one smaller additional setiferous puncture before each large lateral puncture; surface of pronotum with microsculpture similar to that of head, but even finer.

Scutellum (Fig. 1C ) with dense setiferous punctures, surface with very fine and dense microsculpture of transverse waves.

Elytra (Fig. 1C ) broad, slightly wider than long, EW/EL = 1.08, ESL/EL = 0.52, nearly parallel-sided laterally, each elytron with surface covered with dense setiferous punctures, transverse interspaces between punctures about as wide as diameter of punctures; surface between punctures with semigranulose microsculpture. Wings fully developed.

Abdominal tergite II finely punctate; setiferous punctures of other tergites finer and sparser than those of elytra, distinctly becoming sparser toward posterior margin of each tergite, and generally becoming so toward apex of abdomen; tergite VII with whitish apical seam of palisade setae.

Male with first four segments of foretarsus moderately dilated, sub-bilobed, each heavily covered with tenent setae ventrally, segment II slightly narrower than apex of tibia. Tergite VIII with basal ridge complete, slightly arched backward in middle, surface without long seta; sternite VIII (Fig. 2A ) with basal ridge complete, slightly sinuate, with two long setae on each side, apical margin with very shallow and narrow medioapical emargination, a very small triangular area in front of the emargination impunctate; sternite IX (Fig. 2B ) with basal portion long and curved, with a moderately deep arcuate medioapical emargination, with two long setae on each side of the emargination apically; tergite X (Fig. 2C ) with basal side broadly and deeply concave, apical margin rounded, vaguely protruded. Aedeagus in lateral view (Fig. 2F ) with apex of paramere not quite reaching that of median lobe, median lobe bent toward parameral side, without any process at apex; in parameral view (Fig. 2G ) with paramere slightly narrower than median lobe, apical 1/4 gradually narrowed, forming rounded apex, median lobe wide at base, slightly narrowed in middle, distinctly constricted at about apical 1/5, apex subtruncate, with an inconspicuous medioapical emargination (Figs 1E , 2D ); apical portion of paramere with four moderately long apical setae, and two similar subapical setae on each lateral side below apex, underside with numerous sensory peg setae arranged into one characteristic inversed Y-shaped figure at apex (Figs 1D , 2E ).

Female first four segments of fore tarsus similar to those of male, but less dilated; sternite VIII with basal ridge inconspicuous, with 2 long setae on each side; tergite X (Fig. 2H ) with basal side broadly and deeply concave, with subtriangular area in middle more strongly sclerotized and pigmented, apical margin incomplete, forming distinctive M-shaped indention.

Distribution.

Queskallion saetosum sp. nov. is at present known only from the type locality in central Sichuan Province (Fig. 3 ), China, at an altitude of 1600 m. The specimens were collected from stacks of withered grass on the roadside in August.

Etymology.

The specific name is from the Latin adjective saetosus, - a, - um (bristly), referring to the additional setae on the pronotum.

Figures

Figure 1. Q. saetosum sp. nov., morphology A head B pronotum C elytra D underside of paramere E apical portion of median lobe, parameral view. Scale bars: 1 mm (A-C); 0.20 mm (D, E).

Figure 2. Q. saetosum sp. nov., morphology A male sternite VIII B male sternite IX C male tergite X D apical portion of median lobe, parameral view E underside of paramere F aedeagus, lateral view G aedeagus, parameral view H female tergite X. Scale bars: 0.20 mm.

Figure 3. Known distribution of Queskallion species in China, Myanmar and Nepal.