Quedius sagittalis, Zhao, Zong-Yi & Zhou, Hong-Zhang, 2015

Zhao, Zong-Yi & Zhou, Hong-Zhang, 2015, Phylogeny and taxonomic revision of the subgenus Velleius Leach (Coleoptera: Staphylinidae: Staphylininae), Zootaxa 3957 (3), pp. 251-276 : 261-263

2. Quedius (Ve l le iu s) sagittalis sp. nov.

( Fig. 4 C & 6).

Description. Body length about14.0 mm, body width 3.0 mm (EW), HW/PW/EW/AW = 1.0:1.4:1.5:1.4, HL/PL/ EL = 1.0:1.4:1.9.

Body entirely dark brown, head nearly black, pronotum some reddish, hypomera of elytra from humeri to apices yellowish, pronotum and abdomen iridescent, last segment of antenna paler.

Head nearly quadrate, wider than long, HW/HL = 1.0:0.8, eyes large, in dorsal view longer than tempora, HEL/HTL = 1.0:0.5; posterior frontal setiferous puncture positioned before posterior edge of eye and adjacent to eye, two basal setiferous punctures on each side with the outer one smaller than the inner one, temporal setiferous puncture about equally distant to posterior edge of eye and to nuchal constriction; no oblique fovea behind insertion of each antenna, dorsal surface covered with sparse fine punctures and dense microsculpture, the meshes of microsculpture isodiametric on anterior portion but transverse on posterior portion of head.

Antennae with apex of segment III obviously wider than apex of segment I, segments IV and X each shallowly, segments V–IX each deeply bifurcated, segment III longer than segment II, last segment about as long as 2 preceding segments combined.

Left mandible ( Fig. 6 E) with anterior tooth not divided into subteeth, edge before anterior tooth not smoothly curved but forming an angle, posterior tooth present with notch before it very deep, right mandible ( Fig. 6 F) only with one tooth.

Maxillary palpus with last segment lacking seta and nearly fusiform, surface of basal half covered with many longitudinal foveae and of apical half covered with many pores, ratio of segment II–IV as 1.0:0.7:1.0.

Labial palpus with last segment lacking seta and strongly dilated to nearly globose, much wider than penultimate segment, apical portion covered with many pores and apex with developed sensory organ, ratio of segment I–III as 1.0:1.0:1.5.

Neck surface covered with microsculpture consisting of transverse meshes, and also covered with fine punctures sparser than those on head.

Pronotum wider than long, PW/PL = 1.0:0.7; two setiferous punctures in each dorsal row with the anterior one smaller, two setiferous punctures in each sublateral row, the posterior puncture in sublateral row slightly behind the posterior puncture in dorsal row and both behind level of large lateral setiferous puncture; surface covered with very vague but dense transverse microsculpture.

Scutellum densely setose, surface between setae covered with dense transverse microsculpture, anterior basal ridge with middle portion angled backwards but not broken, posterior basal ridge slightly arced forward ( Fig. 4 C).

Elytra slightly wider than long, EW/EL = 1.0:0.9, EL/ESL = 1.0:0.6, surface evenly and densely setose, surface between setae smooth and without micropuncture.

Abdomen with each tergite densely setose, setae gradually becoming sparser towards apex; tergite III lacking and tergite IV–VII bearing one large middle lateral setae on each side, tergite VII bearing whitish apical fringe; tergite VIII bearing many large black setae on apical half.

Apices of meso- and metatarsomere V not dilated.

Male. Sternite VIII bearing many large black setae on apical half, apical margin with a middle emargination, a small area before it without any seta; sternite IX ( Fig. 6 G) with basal portion slender and long, apical portion with a small emargination on apical margin, surface from widest portion to apex covered with dense setae gradually becoming slightly larger towards apex; tergite X ( Fig. 6 H) with basal edge strongly arcuate backwards, apical portion round, not obviously triangle-shaped, apex obtuse, apical 1/3 covered with many large setae and a few smaller setae; aedeagus in lateral view ( Fig. 6 A) with apex of paramere not protruding beyond that of median lobe, the former slightly bent towards median lobe, paramere not suddenly widened below apex, median lobe with an apical hook facing paramere and concaved below the hook, in dorsal view ( Fig. 6 B) paramere narrower than median lobe through whole length, paramere from apex to base firstly slightly widened and then slightly narrowed, median lobe from apex to base just gradually and slightly widened, apical portion of paramere (Fig. C) not divided into two branches but just with a small emargination at apical margin, 2 apical and 2 lateral setae on each side, sensory peg setae on underside of paramere forming two irregular longitudinal groups each consisting of 8 setae and extending from apex just to insertions of lateral setae.

Female. Unknown at present.

Type material. Holotype male, China, Shaanxi Province, Mei County, Taibai Mountain, 1800m, 04.VI.2007, collected by Zhou Hongzhang, deposited in IZ-CAS.

Etymology. The species is named from Latin word sagittalis (meaning arrow-shaped) referring to the pointed middle portion of the anterior ridge of scutellum.

Comparison. Quedius (Velleius) sagittalis is very similar to Q. (V.) japonicus , including body size and color. But the anterior ridge of scutellum in the former species is entire, while the ridge is broken in the latter.

Distribution. At present this new species is known only from Taibai Mountain in Shaanxi Province of China.

Figures

FIGURE 4. Some structures of Velleius. A – B, antenna. (A) Q. (V.) dilatatus, (B) Q. (V.) rectilatus. C – D, head in dorsal view. (C) Q. (V.) dilatatus, (D) Q. (V.) rectilatus, AFSP = anterior frontal setiferous puncture, PFSP = posterior frontal setiferous puncture, (E) pronotum of Q. (V.) dilatatus, DR = dorsal row, SLR = sublateral row (Q. (V.) dilatatus without the posterior puncture), LLSP = large lateral setiferous puncture, (F) elytra of Q. (V.) rectilatus. G – I, scutellum. (G) Q. (V.) dilatatus, (H) Q. (V.) japonicus, (I) Q. (V.) sagittalis, abr = anterior basal ridge, pbr = posterior basal ridge, (J) abdominal tergite V of Q. (V.) dilatatus, LMLS = large middle lateral seta, (K) male abdominal tergite VIII of Q. (V.) elongatus, showing all large setae but not small ordinary ones, (L) male abdominal sternite VIII of Q. (V.) elongatus, showing all large setae and the glabrous area in front of apical emargination. Scales = 0.5 mm.

FIGURE 6. Q. (V.) sagittalis. A – D, aedeagus, (A) lateral view, (B) dorsal view, (C) underside of paramere apex, showing sensory peg setae, (D) apical portion of median lobe in lateral view, E – F, mandibles, dorsal view, (G) male abdominal sternite IX, (H) male abdominal tergite X. Scales = 0.5 mm.