Lathrobium jiuwanshanense X.-B. Lin and Peng, 2022

Lin, Xiao-Bin, Tan, Fei & Peng, Zhong, 2022, New data on the genus Lathrobium Gravenhorst (Coleoptera: Staphylinidae: Paederinae) of Guangxi, South China, Zootaxa 5099 (5), pp. 593-600 : 596-597

Lathrobium jiuwanshanense X.-B. Lin and Peng , new species

( Figs 1B , 3 )

Type material (2♂♂, 1♀). Holotype ♂:“ China: Guangxi,Huanjiang, Jiuwanshan N. R.,Yangmeiao, 25°12’22.15’’N, 108°40’32.01’’E, 1250 m, 25.IV.2021, Tang, Peng, Cai & Song leg.” ( SNUC); Paratypes: 1 ♀: same data as holotype ( SNUC) ; 1 ♂: “ China: Guangxi, Liuzhou City, Jiuwanshan N. R., Yangmei’ao , 25°11’42’’N, 108°38’51’’E, mixed leaf litter, sifted, 1200 m, 24–26.VII.2015, Li & Zhao leg.” ( SNUC) .

Description. Measurements (in mm) and ratios: BL 6.67–7.62, FL 2.86–3.37, HL 0.99–1.22, HW 0.99–1.14, AnL 1.99–2.20, PL 1.24–1.40, PW 1.06–1.26, EL 0.61–0.76, AL 1.46–1.50, HL/HW 1.00–1.07, HW/PW 0.90–0.93, HL/PL 0.78–0.87, PL/PW 1.11–1.19, EL/PL 0.48–0.54.

Habitus as in Fig. 1B . Body blackish brown, legs reddish brown, antennae dark brown to light brown.

Head punctation coarse and moderately sparse, distinctly sparser in median dorsal portion; interstices with distinct microreticulation. Eyes moderately small and composed of approximately 60 ommatidia.

Pronotum with weakly convex lateral margins in dorsal view; punctation similar to that of head; impunctate midline broad; interstices glossy and without microsculpture.

Elytral punctation moderately dense and shallow. Hind wings completely reduced. Protarsomeres I–IV with weak sexual dimorphism.

Abdomen with fine and dense punctation, punctation of tergite VII slightly less dense than that of anterior tergites; interstices with shallow microsculpture; posterior margin of tergite VII without palisade fringe; tergite VIII with weakly pronounced sexual dimorphism.

Male. Sternite VII ( Fig. 3D ) with posterior margin truncate at middle, with modified black setae; sternite VIII ( Fig. 3E ) with wide triangular posterior excision; aedeagus as in Figs 3F, G , with stout ventral process of highly distinctive shape, hooked apically in lateral view; internal sac with one sclerotized spine.

Female. Posterior margin of tergite VIII ( Fig. 3A ) strongly convex. Posterior margin of sternite VIII ( Fig. 3B ) strongly convex and with moderately dense micropubescence; tergite IX ( Fig. 3C ) with short antero-median portion and slender postero-lateral processes; tergite X ( Fig. 3C ) 2.5 times as long as antero-median portion of tergite IX.

Comparative notes. The new species resembles L. maoershanense Peng & Li, 2012 in habitus and the similarly derived morphology of sternites VII–VIII, but differs from this species by the stouter ventral process and the simple internal sac of the aedeagus. For illustrations of L. maoershanense see Peng et al. (2012: figures 1B, 3).

Etymology. The species is named for its type locality (Jiuwanshan Nature Reserve).

Distribution and natural history. Two type localities are situated in the Jiuwanshan Nature Reserve to the north of Huanjiang, northern Guangxi. The specimens were sifted from leaf litter and grass roots in shrub habitats at an altitude of 1200–1250 m.

Figures

FIGURE 1. Male habitus of Lathrobium spp., A L. caiyujiei B L. jiuwanshanense C L. zhusha. Scales: 1.0 mm.

FIGURE 3. Lathrobium jiuwanshanense. A female tergite VIII B female sternite VIII C female tergites IX–X. D male sternite VII E male sternite VIII F aedeagus in ventral view G aedeagus in lateral view. Scales: 0.5 mm.