Hesperus pengi, Cai & Li & Tang, 2024

Cai, Yu-Jie, Li, Yue-Yang & Tang, Liang, 2024, New species group and two new species of the genus Hesperus from China (Coleoptera: Staphylinidae: Philonthina), Zootaxa 5474 (5), pp. 550-562 : 560-561

Hesperus pengi sp. nov.

(Chinese name: ǾK刃Ḇdzûà)

( Figs 11, 12 , 18, 24 , 45–50)

Type material. Holotype. China: ♂ glued on a card with labels as follows: “China: Hainan Prov., Wuzhishan City, Mt. Wuzhishan , 18°53′N, 109°41′E, alt. 1800 m, 20.IV.2012, Peng & Dai leg.” “Holotype / Hesperus pengi / Cai, Li & Tang” [red handwritten label] ( SHNU) . Paratype. 1♀, same data as holotype ( SHNU) .

Description. Measurements of male: BL: 11.40 mm, FL: 5.17 mm. HL: 1.25 mm, HW: 2.01 mm, EYL: 0.63 mm, TL: 0.45 mm, PL: 1.85 mm, PW: 1.68 mm, EL: 2.48 mm, EW: 2.50 mm. HW/HL: 1.61, TL/EYL: 0.72, PL/ PW: 1.10, EL/EW: 0.99.

Measurements of female: BL: 10.35 mm, FL: 5.39 mm. HL: 1.24 mm, HW: 1.74 mm, EYL: 0.68 mm, TL: 0.43 mm, PL: 1.92 mm, PW: 1.67 mm, EL: 2.57 mm, EW: 2.75 mm. HW/HL: 1.40, TL/EYL: 0.64, PL/PW: 1.15, EL/EW: 0.93.

Head, neck and pronotum reddish brown to black; antennae ( Fig. 18 ) with antennomeres 1–7 black, base of antennomere 2 reddish, antennomeres 8–11 creamy white; mandibles red, maxillary and labial palpi reddish brown; elytra reddish-brown, each elytron with a large black spot reaching lateral sides and occupying about half-length of elytron, posterior margins pale yellow; scutellum black; abdomen with segments III–V reddish-brown, segments VI and VII black except for the reddish basal margin of both segments and the broadly yellowish apical margin of segment VII, segment VIII with proximal half yellowish and distal half black, segments IX and X brown; legs reddish brown with femora and coxa black.

Head ( Fig. 24 ) rounded trapezoid, markedly transverse in male (1.61 times as wide as long), less so in female (1.40 times as wide as long), eyes longer than tempora; dorsal surface with large, impressed punctures, forming sinuate row on each side, about half way between midline and eyes consisting of about five punctures, posterior portion of head sparsely punctate; entire head with distinct microsculpture of transverse waves; antennae with antennomere 4 slightly oblong, antennomere 5 about as long as wide, subsequent antennomeres becoming gradually shorter and slightly to more distinctly transverse, antennomeres 6–10 slightly asymmetrical, antennomere 11 almost as long as antennomere 9 and 10 combined.

Pronotum 1.10–1.15 times as wide as long, widest close to anterior angles, distinctly concave in posterior half; dorsal surface moderately densely, irregularly punctate, size of punctures similar to those of head, with broad impunctate midline, surface with distinct microsculpture of transverse waves similar to that of head.

Elytra about as long as wide (0.93–0.99 times as long as wide), with depression between shoulders, densely and finely punctate, punctures separated by about one puncture diameter, with weak indication of a lateral carina in posterior half; pubescence yellow, long and dense along shoulder and posterior elytral margin; scutellum triangular, densely and coarsely punctate, bearing long and yellow pubescence.

Abdomen with tergite III with two basal lines, bent posteriad before reaching spiracle, surface of tergites III– VII with dense and pit-like punctures.

Male. Protarsomeres 1–4 moderately dilated, heart-shaped; sternite VIII with posterior margin emarginate at middle, sternite IX ( Fig. 49 ) with narrow, moderately long, asymmetrical basal portion, apex deeply emarginated, tergite X ( Fig. 50 ) triangular; aedeagus ( Fig 45–48 ) with median lobe and paramere slightly asymmetrical, median lobe narrowed towards apex in ventral view, gradually tapered towards hatchet-like apical hook in lateral view, paramere shorter than median lobe, sharply narrowed into obtusely pointed apex, with eight long setae, two at apex and three on each lateral margin.

Female. Protarsomeres 1–4 less dilated than in male; sternite VIII without medio-apical emargination.

Etymology. The species is named in honor of Dr. Zhong Peng who collected the specimens of the new species.

Distribution. This species is only known in the island of Hainan, China.

Diagnosis. The species can be easily recognized from H. babai by the completely different coloration: head, neck and pronotum reddish brown to black, abdomen with segments III–V reddish-brown. Additionally, the apical portion of median lobe is longer, distinctly bent dorsad in lateral view, paramere sharply narrowed into obtusely pointed apex.

Figures

FIGURES 7–12. Habitus. 7, 8—Hesperus watanabei; 9, 10—H. babai; 11, 12—H. pengi. Scale bars: 1 mm.

FIGURES 13–24. Characters of Hesperus. 13–18—antennae; 19–24—head; 13, 19—H. birmanus; 14, 20—H. flexibilis; 15, 21—H. susannekontrusae; 16, 22—H. watanabei; 17, 23—H. babai; 18, 24—H. pengi. Scale bars: 1 mm.

FIGURES 45–50. Hesperus pengi. 45, 46—aedeagus in lateral view; 47, 48—aedeagus in ventral view; 49—sternite IX of male; 50—tergite X of male. Scale bars: 0.1 mm.