Holotype. China – Xizang Prov. • ♂; glued on a card with two labels as follows: “China: Xizang Prov., Dingjie County, Chentang Town, Xiuxiongma Vill., alt. 27°54'11"N, 87°22'42"E, 2700–3000 m, 25.VI.2021, Peng, Yin & Zhang leg.” “Holotype: Paederuschentangus sp. n., Yang & Peng des. 2024” [red handwritten label]; SNUC. Paratypes. China – Xizang Prov. • 8 ♂♂, 12 ♀♀; Dingjie County, Chentang Town, Xiuxiongma Vill., alt. 27°54'11"N, 87°22'42"E, 2700–3000 m, 25.VI.2021, Peng, Yin & Zhang leg; SNUC • 4 ♂♂, 12 ♀♀; Dingjie County, Chentang Town, Ganma Zangbu, 27°51'38"N, 87°24'59"E, alt. 2300 m, 30.VII.2022, Peng, Song, Yin & Zhang leg; SNUC • 3 ♀♀; Dingjie County, Chentang Town, Ganma Zangbu, 27°51'50"N, 87°24'24"E, alt. 2400 m, 28.VI.2021, Z. Peng leg; SNUC.

Measurements (in mm) and ratios: BL: 9.39–11.22; FL: 4.43–5.00; HL: 1.25–1.37; HW: 1.47–1.57; AnL: 2.78–3.17; PL: 1.34–1.57; PW: 1.42–1.50; EL: 1.05–1.12; EW: 1.49–1.62; AW: 1.62–1.69; AL: 1.72–1.74; HL/HW: 0.84–0.87; HW/PW: 0.98–1.05; HL/PL: 0.87–0.93; PL/PW: 0.95–1.05; EL/PL: 0.71–0.78; diameter of eye: 0.37–0.42.

Habitus as in Figs 1A, 8. Coloration: head and abdomen black; antennae light brown, sometimes antennomeres 4–11 infuscate; pronotum red; elytra black with bluish-green hue; legs black with blackish-brown tarsi.

Head (Fig. 1A) transverse, widest across eyes; punctation coarse and moderately dense; interstices glossy. Eyes distinctly convex. Antennae slender, antennomere 4 approximately 3.8 times as long as broad and antennomere 10 nearly twice as long as broad. Mandibles (Fig. 2A, B) each with apically bifid molar tooth, without evident sexual dimorphism.

Pronotum (Fig. 1A) weakly transverse or as long as broad, strongly convex in cross section; punctures distinctly sparser and shallower than that of head.

Elytra (Fig. 1A) nearly trapeziform; punctation coarse, well defined, and dense. Hind wings reduced. Metatarsomere I shorter than combined length of metatarsomeres II and III.

Abdomen slightly broader than elytra; punctation dense; interstices with distinctly transverse microsculpture; posterior margin of tergite VII without palisade fringe.

Male. Anterior margin of labrum (Fig. 2B) in middle with semicircular median excision; posterior margin of tergite VIII (Fig. 2E) pointed in middle; sternite VII unmodified; sternite VIII (Fig. 2F) with deep posterior excision, this excision approximately 0.4 times as long as sternite VIII; aedeagus as in Fig. 2G–I, ventral plate apically convex in ventral view; dorsal plate asymmetric, apically acute and not reaching apices of parameres in ventral view; parameres weakly asymmetric and apically distinctly curved in lateral view; internal sac with single distinctive sclerotized spine.

Female. Anterior margin of labrum (Fig. 2A) in middle with shallow median excision. Posterior margin of tergite VIII (Fig. 2C) strongly convex; posterior margin of sternite VIII (Fig. 2D) obtusely pointed in middle.

The species was found in three localities in the Chentang area, to the south of Dingjie, southern Xizang. The specimens were sifted from moss, grass roots and loose gravel in shrub habitats at altitudes of 2300–3000 m (Figs 8, 9).

The species is named after its type locality (Chentang).

Based on the sexual characters and the external characters, closer affiliations with other Paederus species from Xizang are not evident. However, the highly similar male sexual characters, particularly the similarly derived morphology of the aedeagus, suggest that P.chentangus is very closely related to P.megascutum Willers, 1999 from Nepal. It differs from P.megascutum by the shape of the head (weakly transverse in P.megascutum), by the shorter elytra, and particularly by the stouter parameres and the curved ventral plate of the aedeagus in ventral view. For illustrations of P.megascutum, see Willers (1999: figs 7, I4, II4).