Clidicus qiuae, Cheng & Yin, 2019

Cheng, Zhi-Fei & Yin, Zi-Wei, 2019, Two new species of Clidicus Laporte, 1832 (Coleoptera: Staphylinidae: Scydmaeninae) from Yunnan, China, Zootaxa 4623 (2), pp. 321-330 : 322-326

Clidicus qiuae sp. nov.

( Figs 1–4 , 7 )

Type material (71 exx). Holotype: CHINA: ♂, ‘ China: Yunnan, Wenshan City , Maguan County (IJẌƃ), Gulinjing Town (Ħẇḃş), Piaochang Village ( ṞFḤ) , Gulinjing N. R. (ĦẇḃssküDṽ), 22°51′20.03″N, 103°59′10.27″E, alt. 1,700 m, 27.ii.2018, Jian-Yue Qiu & Hao Xu leg. / HOLOTYPE (red) ♂, C. qiuae sp. n., det. Cheng & Yin, 2019, SNUC’ (in SNUC) . Paratypes: CHINA: 28 ♂♂, 42 ♀♀, same label data as the holotype, each with a following type label : ‘ PARATYPE (yellow) ♂ (or ♀), C. qiuae sp. n., det. Cheng & Yin, 2019, SNUC’ (all in SNUC) .

Diagnosis. Body often larger than 5.0 mm. Anterior margin of frons broadly emarginate. Anterior margin of labrum with small, triangular emargination at middle. Maxillary palpomeres 2–3 relatively short in relation to palpomere 4. Antennomeres 2–11 each slightly to distinctly elongate. Aedeagus moderately elongate, broadest near middle; parameres symmetric.

Description. Male. BL 5.08–5.30 mm, body ( Fig. 1A ) moderately stout, with flattened subrectangular head and strongly convex pronotum and elytra, covered with coarse and dense setae, reddish-brown, tarsi slightly paler.

Head ( Fig. 2A ) subrectangular and transverse, broadest at temples, HL 0.96–1.05 mm, HW 1.24–1.27 mm; tempora about 3.5× length of eye in dorsal view, evenly rounded; vertex with large and deep posteromedian irregular impression; frons broadly emarginate at anterior margin; clypeus transverse and convex, demarcated from frons by deep and distinct fronto-clypeal groove; supraantennal tubercles small but distinctly elevated. Eyes small, nearly round, not projecting laterally from head silhouette, with fine facets. Punctures on vertex and frons small, but distinct. Setae on head moderately long, sparse and suberect to erect. Antennae ( Fig. 2B ) slender, all antennomeres elongate, relative lengths of antennomeres 1–11: 4.58: 1.0: 1.25: 1.33: 1.33: 1.33: 1.42: 1.42: 1.33: 1.33: 1.58; AnL 3.10–3.47 mm.

Labrum ( Fig. 2C ) subrectangular in dorsal view, with small distinct triangular emargination at middle of anterior margin; anterior margin with single row of five pairs of long and erect setae. Mandible ( Fig. 2D ) subtriangular, with broad base and curved distal tooth; teeth robust; prostheca with short and dense setae from base to nearly middle of mandible. Maxilla ( Fig. 2E ) with triangular stipes bearing single long seta, subtriangular palpifer with long setae on external margin, elongate galea and broad lacinia with short and dense setae. Maxillary palpus with dense short setae and additionally several long thick setae; palpomere 1 minute and elongate; palpomere 2 moderately long and slender, broadened distally and strongly curved; palpomere 3 large and broadened, broadest near apex; palpomere 4 short, subconical. Labium ( Fig. 2F ) elongate, with rectangular mentum about 2.5× as wide as long; prementum moderately large, with anterior surface flattened and divided by longitudinal groove, with several short and long setae. Labial palpus with several long setae; palpomere 1 short and broad, slightly elongate, with one long seta on antero-mesal margin; palpomere 2 strongly elongate, constricted at base and broadened apically, with truncate apex; palpomere 3 subconical with pointed apex, much shorter and narrower than palpomere 2. Lateral lobe of hypopharynx long, with dense microtrichia.

Pronotum in dorsal view inversely subtrapezoidal, broadest near anterior 1/4, PL 1.18–1.27 mm, PWb 0.90–0.96 mm, PWm 1.24–1.33 mm; disc convex, sharply demarcated from narrow posterior ‘collar’ by narrow transverse groove with small, slightly unevenly distributed pits. Punctures and setae on disc similar to those on head.

Elytra in dorsal view oval, broadest near anterior 2/5, strongly narrowing toward apices, EL 2.88–3.10 mm, EW 1.89–1.95 mm, EI 1.50–1.64. Each elytron bears five dorsal and one lateral rows of large and deep pits, second row shortened anteriorly, cuticle between rows with fine and dense setiferous punctures; setae moderately long, denser and thicker than those on head and pronotum, recumbent towards apex. Hind wings absent. Scutellum hardly visible.

Aedeagus ( Fig. 3 A–C) stout, AeL 1.30–1.35 mm, in lateral view strongly curved; parameres symmetric, slen- der, much longer than median lobe, strongly sclerotized, with blunt apices, base and each internal edge fused with median lobe. Sperm pump ( Fig. 3D ) with largest diameter at external margins of funnels, 0.63–0.68 mm in length (measured between external margins of funnels), short and stout, with short basal funnel and longer distal funnel, distance between funnels moderately long, lumen of internal duct broadened between funnels.

Female ( Fig. 1B ). Externally similar to the male, but differs in much shorter antennae, and relatively stouter elytra. Measurements: BL 4.78–5.58 mm; HL 0.93–1.02 mm; HW 1.18–1.40 mm; AnL 2.92–3.02 mm; PL 1.18– 1.36 mm; PWb 0.81–1.02 mm; PWm 1.24–1.36 mm; EL 2.67–3.22 mm; EW 1.86–2.17 mm; EI 1.42–1.49 mm. Female genitalia ( Fig. 3E ) with long and entangled ductus of complicated form around base of spermatheca; bursa copulatrix elongate, finger-shaped; spermatheca ( Fig. 3F ) strongly elongate, 0.38–0.41 mm (largest diameter of the spermatheca) long, with long connecting duct of accessory gland; proctiger rhomboidal, slightly wider than long, posterior margin densely fringed with long and dense setae; coxites elongate, 1.5× as long as wide, apex rounded, with setose margin.

Comparative notes. The new species is morphologically close to several congeners from Indochina, i. e., C. beroni Orousset , C. bellator Jałoszyński, Hlaváč & Nomura , C. rufescens Jałoszyński, Hlaváč & Nomura , and C. omoios Jałoszyński, Hlaváč & Nomura , sharing with them a more or less similarly general stout aedeagus with sym- metric parameres. Clidicus qiuae can be readily separated from these species by the following features:

- from C. beroni by a larger body size (5.08–5.30 mm vs. 4.20 mm), laterally expanded parameres, and a relatively larger distal funnel of a much less elongate sperm pump;

- from C. bellator by a larger body size (5.08–5.30 mm vs. 4.15–4.40 mm), more elongate antennomeres, a much more elongate sperm pump, and a different form of the spermatheca;

- from C. rufescens by a much larger body size (5.08–5.30 mm vs. 3.45–3.72 mm), an impressed anterior margin of the frons (flat in C. rufescens ), the more elongate antennomeres, and different structures of the aedeagus, sperm pump, and spermatheca;

- from C. omoios by a larger body size (5.08–5.30 mm vs. 4.22–4.40 mm), the more elongate antennomeres, a more elongate aedeagus, and different forms of the sperm pump and spermatheca.

Comments. All individuals were collected under moist, thick layer of leaf litter within an hour in the morning. The collecting site was on a slope at the edge of the forest, with the searching area of approximately 30 m 2 ( Fig. 4 A–B). Both collectors were looking for larvae of cetoniine beetles beneath the leaf litter layer, and then noticed the red, shining reflection of these large-sized scydmaenines after stirring the litters. After being exposed, the beetles were observed crawling around on the ground and the surface of the litter layer ( Fig. 4 C–D).

Distribution. Southern China: Yunnan ( Fig. 7 ).

Etymology. The new species is named after our friend, Jian-Yue Qiu, who was one of the collectors of the new species.

Figures

FIGURE 1. Dorsal habitus of Clidicus qiuae. A. Male. B. Female. Scale bars: 2 mm.

FIGURE 2. Diagnostic features of Clidicus qiuae male. A. Head dorsum. B. Left antenna. C. Labrum. D. Right mandible. E. Left maxilla. F. Labium. Scale bars: 0.5 mm in A–B; 0.2 mm in C–F.

FIGURE 3. Diagnostic features of Clidicus qiuae (A–D. Male. E–F. Female). A–C. Aedeagus, dorsal (A), lateral (B), and ventral (C). D. Sperm pump. E. Female genital segment. F. Spermatheca, enlarged. Scale bars: 0.5 mm in A–D; 0.2 mm in E; 0.1 mm in F.

FIGURE 4. Collecting environment of Clidicus qiuae. A, B. Collecting site—a slope at the edge of the forest. C, D. Exposed adults of Clidicus qiuae after the leaf litter was stirred (pictures provided by Hao Xu).

FIGURE 7. Distribution of extant species of Clidicus.