Quedius

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 : 266-268

5. Quedius (Ve l le iu s) dilatatus ( Fabricius 1787)

( Fig. 4 A & 9).

Fabricius 1787: 220 (originally in Stahylininus; Type locality: Halae Saxonum); Westwood 1838: 164 ( Velleius ; habitat); Westwood 1838: 15; Erichson 1839: 484; Erichson 1840: 534; Kraatz 1857: 490; Sharp 1889: 29; Porta 1907: 104; Steel 1952: 278; Nakane 1963: 94; Coiffait 1978: 285; Naomi 1986: 242; Watanabe 1990: 61; Cho 1996: 114; Herman 2001: 3305 (complete list of references).

Synonymy:

Staphylinus serraticornis Schrank 1798: 641 ; Erichson 1839: 485; Erichson 1840: 524; Kraatz 1857: 490; Porta 1907: 104; Coiffait 1978: 285; Herman 2001: 3306 (complete list of references).

Staphylinus concolor Marsham 1802: 498 ; Leach 1819: 172; Erichson 1839: 485; Erichson 1840: 524; Kraatz 1857: 490; Porta, 1907: 104; Coiffait 1978: 285; Herman 2001: 3306 (complete list of references).

Redescription. Body length about 19.0 mm, body width 5.0 mm (EW), HW/PW/EW/AW = 1.0:1.6:1.6:1.2, HL/ PL/EL = 1.0:1.5:1.9.

Body entirely dark brown, pronotum and elytra more reddish-brown, humeri of elytra yellowish, antennae with last segment paler, pronotum and abdomen iridescent.

Head nearly quadrate, wider than long, HW/HL = 1.0:0.8, eyes large, longer than tempora in dorsal view, HEL/ HTL = 1.0:0.7; posterior frontal setiferous puncture positioned behind level of posterior side of eye and separated from posteromedian edge of eye by about two diameters of puncture, one or two basal setiferous puncture on each side and much smaller than posterior frontal setiferous puncture, temporal setiferous puncture slightly closer to nuchal constriction than to posterior edge of eye; one oblique narrow fovea on each side just behind insertion of antenna, dorsal surface covered with sparse fine punctures and dense microsculpture consisting of isodiametric meshes.

Antennae with apex of segment III wider than apex of segment I, segments IV–X each shallowly bifurcated, segment IV even not bifurcated, segment III longer than segment II, last segment about as long as 2 preceding segments combined.

Left mandible ( Fig. 9 E) with anterior tooth divided into two subteeth about equally sized, edge before anterior tooth smoothly curved, posterior tooth absent, right mandible ( Fig. 9 F) with three teeth.

Maxillary palpus with last segment parallel-sided and lacking seta, surface of basal half covered with many longitudinal foveae and of apical half covered with many pores, ratio of length of segments II–IV 1.0:0.8:0.8. Labial palpus with last segment fusiform and lacking seta, apex truncated, surface of apical portion covered with many pores, ratio of length of segments I–III 1.0:1.0:1.3.

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

Pronotum wider than long, PW/PL = 1.0:0.8; two large setiferous puncture in each dorsal row, each puncture accompanied by a much smaller puncture, one large setiferous puncture in each sublateral row, large lateral setiferous puncture behind level of sublateral row but before level of posterior puncture in dorsal row; dense microsculpture on anteromedian surface similar to those on head, but the meshes gradually becoming more transverse and vaguer towards lateral and posterior margin.

Scutellum densely setose, surface between setae covered with dense transverse wave-shaped microsculpture, anterior basal ridge with middle portion nearly straight, posterior basal ridge slightly arced backward ( Fig. 4 A).

Elytra about as wide as long, EL/ESL = 1.0:0.6; surface evenly and densely setose, surface between setae covered with dense micropunctures.

Abdomen with each tergite evenly and densely setose, tergite III–VII bearing large middle lateral setae, tergite VII bearing whitish apical fringe, tergite VIII bearing many large black setae on apical half.

Apices of meso- and metatarsomere V dilated.

Male. Sternite VIII bearing many large black setae on apical half, apical margin with a middle emargination and a small area before it glabrous; sternite IX ( Fig. 9 G) with basal portion slender and not very long, apical margin with a shallow middle emargination, surface from widest portion to apex covered with dense setae gradually becoming slightly larger towards apex; tergite X ( Fig. 9 H) with basal edge broadly arcuated backwards, apical portion nearly triangle-shaped and apex obtuse not truncated, surface of apical 1/3 bearing many large black setae; aedeagus in lateral view ( Fig. 9 A) with apex of paramere protruding slightly beyond apex of median lobe, paramere suddenly widened below apex, median lobe with a small hook facing paramere below apex ( Fig. 9 D), not appreciably concave below the hook, in dorsal view ( Fig. 9 B) paramere covering median lobe except on apical portion, apex of paramere ( Fig. 9 C) divided into two branches separated from each other, 2 apical and 2 lateral setae on each side, sensory peg setae on underside of paramere forming two irregular group each including about 20 setae and extending from apex towards base and beyond insertions of lateral setae.

Female. Tergite X ( Fig. 9 I) with basal side broadly and smoothly arcuated backwards, apical portion trilobed with two lateral lobes smaller than the middle lobe, apical portion of middle lobe nearly triangle-shaped but with apex obtuse, apical margin bearing several long setae.

Specimens examined. 1 male, China, Beijing, Changping, Huyu, 14.VII.1997, collected by Zhou Haisheng, deposited in IZ-CAS; 1 male, China, Shaanxi Province, Taibai Mountain, Songping Temple, 15.VIII. 1981; 1 female, Denmark, Bognaes, 19.X.2004, collected by O. Martin, deposited in IZ-CAS.

Comparison. Quedius (Velleius) dilatatus can be easily distinguished from other species by very shallowly bifurcated antennal segements IV–X. Its difference from Q. (V.) circumipectus was mentioned above.

Distribution. Quedius (Velleius) dilatatus is widely distributed from western Europe to eastern Asia. Absence of records in Middle Asia is most probably due to insufficient collecting there.

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 9. Q. (V.) dilatatus. 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; I, female abdominal tergite X. Scales = 0.5 mm.