Diartiger yaoluopingensis Yin

Yin, Zi-Wei & Li, Li-Zhen, 2013, Notes on synonymy of Diartiger Sharp with Microdiartiger Sawada (Coleoptera: Staphylinidae: Pselaphinae), with description of two new species from East China, Zootaxa 3717 (3), pp. 369-376 : 373

Diartiger yaoluopingensis Yin and Li, new species

( Figs 1 B, 3, 4)

Type material (27 ♂♂, 2 ♀♀). Holotype: CHINA: ♂, labeled ‘ China: SW Anhui, Liu’an City, Yue’xi County, Yaoluoping N. R., 30°58′24″N, 114°03′47″E, path near Zhao Guan, under rock, colony of Lasius sp., ca. 1235 m, 20.vi.2013, Dai & Peng leg. (SNUC)’. Paratypes: CHINA: 24 ♂♂, 2 ♀♀, same label data as holotpye; 2 ♂♂, same label data, except ‘30°59′05″N, 114°04′40″E, roadside near the resort, ca. 1055 m, 17.vi.2013 ’ (all SNUC).

Description. Male. Body ( Fig. 1 B) length 2.03–2.16 mm; reddish brown. Head longer than wide, HL 0.42– 0.43 mm, HW 0.27–0.28 mm; clypeus with angulate anterior margin; eyes each composed of about 20 facets; antennomeres IV ( Fig. 3 A) more than 1.4 times as long as III. Pronotum about same length as width, PL 0.39–0.42 mm, PW 0.38–0.40 mm. Elytra ( Fig. 3 E) wider than long, EL 0.54–0.57 mm, EW 0.76–0.80 mm; with distinct microsculpture; lacking tufts of setae at posterolateral margins, with bigger triangular, posteriorly-narrowed trichomes at posterolateral margins ( Fig. 3 F). Metathoracic wings fully-developed. Mesoventrite ( Fig. 3 G) with short median carina, metaventrite ( Fig. 3 G) convex, both meso- and metaventrites with sparse, thick setae along midline. Fore legs ( Fig. 3 B) simple; mesotrochanters ( Fig. 3 C) with large, triangular ventral spine, mesotibiae with small preapical tubercle; metatrochanters ( Fig. 3 D) with short, tiny ventral tubercle. Abdomen ( Fig. 3 H) wider than long, AL 0.68–0.74 mm, AW 0.84–0.88 mm; composite tergite with transverse thick basolateral trichomes curved mesally, first pair of paratergites with linear trichomes ( Fig. 3 I). Aedeagal length 0.4 mm; median lobe pointed apically in lateral view (Figs J–L).

Female. Antennae lack obvious sexual dimorphism. Identical to male except as follows: mesofemora and mesotibiae lacking spines or tubercles. Measurements: BL 2.69–2.77 mm, HL 0.45–0.46 mm, HW 0.53–0.54 mm, PL 0.55–0.56 mm, PW 0.59–0.60 mm, EL 0.71–0.73 mm, EW 1.12–1.13 mm, AL 0.98–1.02 mm, AW 1.10–1.12 mm.

Comparative notes. Diartiger yaoluopingensis is most similar to D. kubotai in sharing the similar ventral spine of the mesotrochanters, and lack of denticles on the mesofemora. The two species can be separated by the aedeagal form, and their distribution. The angulate clypeal anterior margin alone also quickly separates the new species from all other congeners which have round clypeal anterior margins.

Distribution. East China: Anhui Province.

Biology. Adults of the new species were collected from nests of Lasius sp. located under stones ( Fig. 4A ). A large number of Diartiger dentatus sp. n. and a small series of D. songxiaobini (see below) were collected in the same nests.

Etymology. The species is named after its type locality, Yaoluoping Natural Reserve.

Diartiger japonicus -group

Diagnosis. Head and pronotum sparsely covered with thick, suberect setae; maxillary palpi relatively large, narrowed apically; mesotrochanters lacking spine; elytra with distinct microsculpture; trichomes of elytra narrow, linear; basal cavity of composite tergite lacking ridge; aedeagal median lobe apparently divided to two parts, with large apical part.

Included species: D. japonicus , D. thinhi , D. songxiaobini .

Figures

FIGURE 1. Dorsal habitus of Diartiger dentatus (A) and D. yaoluopingensis (B). Scales: 0.5 mm.

FIGURE 3. Diagnostic features of Diartiger yaoluopingensis. A. Antenna. B. Fore leg. C. Mid leg. D. Hind leg. E. Left elytron. F. Elytral trichome, enlarged. G. Meso- and metaventrite. H. Left half of abdomen. I. Abdominal trichome, enlarged. J. Aedeagus, in dorsal view. K. Same, in lateral view. L. Same, in ventral view. Scales: all 0.2 mm, except F, I = 0.1 mm.

FIGURE 4. A. General habitat of Diartiger dentatus and D. yaoluopingensis. B. Diartiger dentatus and D. yaoluopingensis in a nest of Lasius sp. C. A living Diartiger dentatus.