Sinlathrobium chenzhilini X. Chen & Z. Peng 2024, sp. nov.

Sinlathrobium chenzhilini X. Chen & Z. Peng sp. nov. Figs 1 B, 1 E, 3 Material examined. Holotype. China – Guangxi Prov. • ♂; glued on a card with two labels as follows: “ China: Guangxi Prov., Xing’an County, Maoer Shan, 25°52'27''N, 110°24'44''E, alt. 1940 m, 29. VII. 2014, Peng, Song, Yu & Yan leg. ” “ HOLOTYPE: Sinlathrobium chenzhilini sp. nov., Chen & Peng des. 2024 ” [red handwritten label]; SNUC. Paratypes. China – Guangxi Prov. • 7 ♂♂, 5 ♀♀; Xing’an County, Maoer Shan, 25°52'27''N, 110°24'44''E, alt. 1940 m, 29. VII. 2014, Peng, Song, Yu & Yan leg; SNUC • 2 ♂♂; Xing’an County, Maoer Shan, 25°53'15''N, 110°25'47''E, alt. 2030 m, 30. VII. 2014, Peng, Song, Yu & Yan leg; SNUC. Description. Measurements (in mm) and ratios: BL 6.12–7.78, FL 3.67–3.89, HL 0.89–0.94, HW 1.04–1.09, PL 1.11–1.20, PW 0.96–1.05, EL 1.07–1.15, AL 1.81–1.91, AeL 1.04–1.14, HL / HW 0.85–0.87, HW / PW 1.03–1.08, HL / PL 0.78–0.80, PL / PW 1.14–1.16, EL / PL 0.95–0.96. Habitus as in Fig. 1 B. Coloration: body black, elytra with extensive orange spot in postero-lateral angles, this spot reaching posterior and lateral margins, near suture; legs with the femora blackish, tibiae dark brown and tarsi brown; antennae dark brown to brown. Head (Fig. 1 E) transverse, widest across eyes; punctation coarse and very dense, in median dorsal portion and on frons distinctly sparser; interstices with shallow microsculpture. Eyes large and bulging, 0.90–0.92 times as long as postocular region in dorsal view. Antennae not particularly slender. Pronotum (Fig. 1 E) nearly parallel-sided; punctation distinctly sparser and distinctly coarser than that of head; interstices without microsculpture and glossy. Elytra (Fig. 1 E) broader than pronotum; humeral angles pronounced; punctation coarse and rather dense; interstices without microsculpture and glossy. Hind wings fully developed. Abdomen somewhat narrower than elytra; tergites III – VI with very fine and dense punctation, tergites VII – VIII with distinctly sparser punctation; posterior margin of tergite VII with palisade fringe. Male. Sternites III – VI unmodified; sternite VII (Fig. 3 D) strongly transverse, with shallow median impression without modified pubescence, posterior margin broadly concave; sternite VIII (Fig. 3 E) transverse, with shallow median impression posteriorly, this impression without modified setae, posterior excision V-shaped and moderately deep; aedeagus as in Fig. 3 F, G, ventral process symmetric, dorsal plate long and strongly sclerotized. Female. Tergite VIII (Fig. 3 A) with broadly convex posterior margin; sternite VIII (Fig. 3 B) weakly oblong, and with strongly convex posterior margin; anterior portion of tergite IX (Fig. 3 C) divided in middle, tergite X (Fig. 3 C) approximately twice as long as tergite IX in the middle. Distribution and biological notes. The type locality is situated in the Maoer Shan to the north of Guilin, northern Guangxi. The specimens were sifted from leaf litter and dead wood in mixed deciduous forests at altitudes from approximately 1940 up to 2030 m. Etymology. This species is dedicated to Zhi-Lin Chen, who supported us on our field trips. Comparative notes. The highly similar male sexual characters, particularly the shape of the male sternites VII – VIII and the similarly derived morphology of the aedeagus, suggest that S. chenzhilini is very closely related to S. assingi sp. nov. and S. lobrathioides (Assing, 2012). It differs from S. assingi by the coloration of legs, particularly by the distinctly sparser and finer punctation of the pronotum, and by the differently shaped ventral process of the aedeagus. It differs from S. lobrathioides by the somewhat longer elytra, particularly by the sparser punctation of the head and pronotum, and by the longer dorsal plate of the aedeagus. For illustrations of S. assingi see Figs 1 A, 1 D, 2.