Pachypaederus kongshuhensis Li, 2021

Li, Xiaoyan, Cai, Yanpeng & Chen, Haifeng, 2021, The third species of the genus Pachypaederus Fagel, 1958 (Coleoptera, Staphylinidae, Paederinae) from the Oriental region, ZooKeys 1037, pp. 15-22 : 15

Pachypaederus kongshuhensis Li sp. nov. Figures 1 , 2 , 3

Type material.

Holotype: ♂, China: Yunnan Province: Tengchong County, Mingguang Town, Kongshuhe County (空树河村), 2100 m elev., 25.7245°N, 98.6341°E, 30.VI.2016, coll. by Xiaoyan Li (IZ-CAS). Paratypes: ♂, 2 ♀♀, same data as holotype (IZ-CAS).

Description.

BL: 8.7-9.0 mm; FL: 3.6-3.8 mm. HL: 1.08 mm; HW: 1.25 mm; PL: 1.39 mm; PW: 1.17 mm; EL: 1.08 mm; EW: 1.39 mm; EYL: 0.36 mm; POL: 0.50 mm.

Body glossy with typical " Paederus " color pattern; head and two apical segments of abdomen, the apical half of femora, and basal two-thirds of elytra dark blue; other parts brown; antennomeres 1 and 2 and 9-12 brownish yellow. Abdominal segments 4-6 with black patches in middle, and patches decreasing in size anteriad.

Head wider than long (average HL/HW = 0.86). Eyes moderately large (average HL/EYL = 3.0), protruding laterally. Diameter of eye longer than gena and shorter than temple (average ratio, gena: eye: temple = 0.70: 1: 1.38). Surface of head smooth. Vertex and frons glabrous with sparse punctures, lateral portions of head with more denser, shallower, and coarser punctures which are irregularly distributed and of variable size.

Antennae filiform and densely pubescent, starting from antennomere 9. Ventral portion of neck with a reversed V-shaped protrusions.

Pronotum slightly longer than wide (average PL/PW = 1.12). Scutellum glossy with reticulate microsculpture and fine setiferous punctation. Mesoventrite pressed, surface smooth, with fine microsculpture, and anterior margins ridged. Metaventrite small with anterior portion even and posterior surface pressed with fine microsculpture.

Elytra trapezoidal-sided, longer than wide (average EL\EW = 0.79 and ESL/EL = 0.68), wings reduced completely. Surface uneven, lustrous, with fine reticulate microsculpture, punctures smaller and denser than that on pronotum, diameter of a puncture usually shorter than interval between punctures.

Tergites III-VI of abdomen with setiferous punctures small and sparse; basal area of each tergite without distinct punctate row. Sternites with punctation similar to that on tergites.

Male. Labrum (Fig. 1B ) narrower than in female, with two small pairs of teeth on anterior margin. Tergite VIII with punctures denser and larger than those on tergites III-VII. Sternites III-VII with setae slightly directed mediad. Sternite VII with microsculpture and punctures much denser than those on sternites III-VI, posterior margin broadly notched. Sternite VIII with deep, parallel-sided, median incision, base of incision truncate, depth longer than half the length of sternite (Fig. 1F ). Sternite IX asymmetrical, apex slightly emarginate and inner ridge symmetrical (Fig. 1G ).

Female. Labrum (Fig. 1C ) well developed, distinctly wider than that in male, two pairs of anterior teeth distinctly larger and sharper. Sternite VIII deeply notched as in Figure 1D . Sternite IX (Fig. 1E ) with basal part bilobed and gradually narrowed apically, posterior margin shallowly emarginated in middle.

Aedeagus (Figs 2A-C , 3A-C ), robust and asymmetrical. AEL = 2.27 mm, AEW = 0.5 mm. Parameres symmetrical and filiform in shape; posterior part slightly clavate. Dorsal plate long and asymmetrical, gradually narrower posteriad and apical part rather sharp and curved leftward in dorsal view. Ventral plate short, with apex broadly round. Internal sac complex and exposed in ventral side, the interior armature with several elongate sclerites and several broad and lamelliform sclerites.

Diagnosis.

The new species Pachypaederus kongshuhensis sp. nov. can be easily distinguished from the two Oriental congeners by a combination of bicolored body and the morphology of the aedeagus. Pachypaederus pallitarsis is completely black, while in P. capillaris , the apex of the dorsal plate faces to the left and there are fewer sclerites in the internal sac of the aedeagus.

Distribution.

The species is known only from westernmost Yunnan Province, China, at an altitude of 2100 m. The specimens were collected in June as they were moving under fresh grass along the sides of a river.

Etymology.

The specific epithet is derived from the type locality, Kongshuhe, a mountain village in westernmost Yunnan Province, China, near the border between Myanmar and China.

Figures

Figure 1. Pachypaederus kongshuhensis Li, sp. nov., morphology A habitus B labrum and mandibles in male C labrum and mandibles in female D sternite VIII in female E sternite IX and lateral proctiger in female F sternite VIII in male G sternite IX in male. Scale bars: 1.0 mm (A); 0.2 mm (B-G).

Figure 2. Pachypaederus kongshuhensis Li, sp. nov., morphology A aedeagus, in ventral view B aedeagus, in lateral view C aedeagus, in dorsal view. Scale bars: 0.2 mm.

Figure 3. Pachypaederus kongshuhensis Li, sp. nov., morphology A aedeagus, in ventral view B aedeagus, in lateral view C aedeagus, in dorsal view. Scale bars: 0.2 mm.