Lathrobium gutianense Peng and Li

Peng, Zhong, Li, Li-Zhen & Zhao, Mei-Jun, 2014, Seventeen new species and additional records of Lathrobium (Coleoptera, Staphylinidae) from mainland China, Zootaxa 3780 (1), pp. 1-35 : 15-17

Lathrobium gutianense Peng and Li , new species

( Figs 9 B, 11)

Type material. (1 ♂, 1 ♀). HOLOTYPE: ♂, labelled ‘ CHINA: Zhejiang Prov., Kaihua County, Gutian Shan, 29°14'N, 118°06'E, 20.vi.2013 alt. 320 m, Jia-Yao Hu leg.’ ( SNUC). PARATYPES: 1 ♀, same label data as holotype ( SNUC).

Description. Measurements (in mm) and ratios: BL 10.73–11.50, FL 5.17–5.39, HL 1.46–1.48, HW 1.62– 1.65, AnL 3.06–3.10, PL 1.85–1.87, PW 1.65–1.67, EL 0.89–0.93, AL 1.60, HL/HW 0.90, HW/PW 0.98–0.99, HL/PL 0.79–0.80, PL/PW 1.12, EL/PL 0.48–0.49.

Habitus as in Fig. 9 B. Body brown with paler apex, legs light brown to yellowish brown, antennae light brown to reddish brown.

Head weakly transverse; punctation coarse and dense, sparser in median dorsal portion; interstices with shallow microreticulation. Eyes 0.32–0.34 times as long as postocular region in dorsal view and composed of nearly 70 ommatidia.

Pronotum with weakly convex lateral margins in dorsal view; punctation somewhat sparser than that of head; impunctate midline narrow; interstices without microsculpture.

Elytra short; punctation moderately dense, shallow, and moderately defined. Hind wings completely reduced. Protarsi with weakly pronounced sexual dimorphism.

Abdomen with fine and dense punctation, that of tergite VII slightly sparser than that of anterior tergites; interstices with very shallow microsculpture; posterior margin of tergite VII without palisade fringe; tergite VIII ( Fig. 11 A) without sexual dimorphism, posterior margin nearly truncate in both sexes.

Male. Sternites III–V unmodified; sternite VI ( Fig. 11 D) with very shallow median impression posteriorly, this impression with dense short setae; sternite VII ( Fig. 11 E) strongly transverse, asymmetric, with deep median impression posteriorly, this impression with dense short setae and additional stout black setae of different lengths along posterior margin of this impression, posterior margin broadly and asymmetrically concave; sternite VIII ( Fig. 11 F) asymmetric, with deep, asymmetric and weakly oblique median impression posteriorly, this impression with numerous short black setae in the middle and delimited by cluster of moderately modified short darkish setae on one side, posterior excision distinctly asymmetric, deep, and in asymmetric position; aedeagus as in Figs 11 G, H, ventral process strongly curved subapically and weakly hooked apically in lateral view; dorsal plate with moderately long sclerotized apical portion and somewhat shorter lamellate basal portion; internal sac with pair of large spines and with additional series of numerous weakly sclerotized small spines apically ( Fig. 11 I).

Female. Sternite VIII ( Fig. 11 B) longer than that of male, posterior margin distinctly produced; tergite IX ( Fig. 11 C) with moderately long antero-median portion without median suture, and with moderately long postero-lateral processes; tergite X 2.3 times as long as antero-median portion of tergite IX ( Fig. 11 C).

Comparative notes. As can be inferred from the highly similar sexual characters, L. gutianense is most likely the adelphotaxon of the geographically close of L. zhaotiexiongi Peng & Li, 2012 , from which it differs by the chaetotaxy of the male sternite V (unmodified), the chaetotaxy of the male sternite VII (impression more densely furnished with modified short setae), the shape and chaetotaxy of the male sternite VIII (posterior margin not bisinuate and less furnished with modified setae), and particularly by the morphology of the aedeagus (ventral process shorter). For illustrations of L. zhaotiexiongi see Peng et al. (2012b). Lathrobium gutianense is distinguished from the sympatric L. nannani sp. n. by greater body size, by the shape and chaetotaxy of the male sternites VII and VIII, as well as the morphology of the aedeagus (shape of ventral process and dorsal plate, internal sac with numerous weakly sclerotized small spines apically).

Distribution and biological notes. The type locality is situated in the Gutian Shan to the northwest of Kaihua, western Zhejiang. The specimens were sifted from leaf litter, grass and humus from the floor of a hardwood forest with beech and Rosaceae at an altitude of 320 m (Hu, pers. comm.).

Etymology. The species is named after its type locality.

Figures

FIGURE 9. Habitus of Lathrobium spp., A — L. fengae; B — L. gutianense; C — L. nannani. Scale bars: 1.0 mm.

FIGURE 11. Lathrobium gutianense. A — female tergite VIII; B — female sternite VIII; C — female tergites IX – X. D — male sternite VI; E — male sternite VII; F — male sternite VIII; G — aedeagus in ventral view; H — aedeagus in lateral view; I — sclerotized internal structure of aedeagus in lateral view. Scale bars: A – H: 0.5 mm; I: 0.1 mm.