Lesteva (s. str.) obesa Cheng, Li & Peng, 2019

Cheng, Zhi-Fei, Li, Li-Zhen & Peng, Zhong, 2019, New species and new records of Lesteva Latreille, 1797 (Coleoptera Staphylinidae: Omaliinae) from China, Zootaxa 4560 (1), pp. 1-39 : 19-20

Lesteva (s. str.) obesa Cheng, Li & Peng , new species

( Figs 16A , 18 A–B, 19A–C, 34)

Type material (1 ex.). Holotype: ♂: ‘ China: Chongqing City (重庆市), Chengkou County (城口县), Mt East Dabashan (东大巴山), upper Huang’an Gou (黄安沟), N31.51.785, E109.09.459, alt. 2039 m, 22–23.iv.2008, Hao Huang & Wang Xu leg. ’ / HOLOTYPE (red), L. obesa sp. nov., det. Cheng, Li & Peng, 2019, SNUC .

Description. Measurements (in mm) and ratios: BL 2.50; FL 1.72; HL 0.41; HW 0.53; PL 0.53; PW 0.60; EL 1.13; EW 1.29; HL/HW 0.77; PL/PW 0.88; EL/EW 0.88; PL/EL 0.82; AnL 1.38; AeL 0.50.

Habitus as in Fig. 16A . Reddish brown, head usually darker, blackish brown; mouthparts and antennae fuscous brown; elytra reddish brown, but lateral and posterior margin paler; elytra with obscure oblique dark red maculae, extending from shoulders toward suture in middle of the elytra; femora fuscous brown, tibiae paler, tarsi yellowish brown. Pubescence of body pale, evident and recumbent.

Head subtriangular, with very coarse and dense punctation, widest across eyes; eyes moderately large and prominent, twice as long as temples; ocelli distinct, distance between ocelli 1.22 times as long as distance between ocellus and inner margin of the compound eye. Antennae elongate, relative lengths of the antennomeres I–XI: 1.54: 1: 1: 1.08: 1.08: 1.08: 1: 1: 1: 1: 1.77.

Pronotum subcordate, distinctly convex, moderately transverse widest near anterior third; lateral margins arcuate at anterior two-thirds and nearly straight at posterior third; punctation and pubescence coarser and sparser than those on head; disc with shallow U-shaped impression. Scutellum subtriangular, with fine and sparse punctation and pubescence.

Elytra subtrapezoidal, gradually dilated posteriorly, posterior angles broadly rounded; punctation and pubescence distinctly finer and sparser than those on pronotum.

Abdomen broad, widest at segment IV (first visible abdominal segment) then narrowed posteriorly; surface of tergites somewhat closely covered with very fine punctation and pubescence, without microsculpture; tergite V with a pair of large and moderately transverse tomentose patches.

Male. Apical margin of the tergite VIII ( Fig. 18A ) weakly concave; sternite VIII ( Fig. 18B ) transverse, apical margin strongly concave. Median lobe of the aedeagus ( Figs 19 A–C) significantly wide basally, narrowing toward apex, slightly longer than parameres; parameres somewhat asymmetrical, with four short apical setae.

Female. Unknown.

Comparative notes. Based on the coloration of the body, punctation and pubescence of the head and pronotum and shape of the median lobe of the aedeagus, the new species is most similar to L. qinlingmontis Rougemont (Shaanxi: Qinling Shan), from which it can be distinguished by a shallow U-shaped impression on the disc of the pronotum, shapes of the elytra and slender parameres. For illustrations of L. qinlingmontis see Rougemont. (2017: 3, 3a).

Distribution and natural history. The type locality is situated in Mt. East Dabashan to the Chengkou County, northern Chongqing, near Shaanxi Province ( Fig. 34 ). The specimen was sifted from leaf litter near a stream in mixed deciduous forests at an altitude of 2039 m.

Etymology. The specific epithet ‘ obesa ’ mean ‘obese’, referring to the morphology of the body in the male of the new species.

Figures

FIGURE 16. Habitus (males) of Lesteva: A—L. obesa sp. nov.; B—L. ochra. Scale bar: 1.0 mm.

FIGURE 18. Abdominal tergite VIII and sternite VIII (males, dorsal view) of Lesteva: L. obesa sp. nov. (A—abdominal tergite VIII, B—abdominal sternite VIII); L. ochra (C—abdominal tergite VIII, D—abdominal sternite VIII); L. pulcherrima (E— abdominal tergite VIII, F—abdominal sternite VIII); L. rufimarginata (G—abdominal tergite VIII, H—abdominal sternite VIII). Scale bar: 0.1 mm.

FIGURE 19. Aedeagus of Lesteva (A–C. L. obesa sp. nov. Male. D–F. L. ochra Male): A–C. Aedeagus, in dorsal (A), ventral (B) and lateral (C) view; D–F. Aedeagus, in dorsal (A), ventral (B) and lateral (C) view. Scale bar: 0.2 mm.

FIGURE 34. Distribution of 24 species of Lesteva in China: 1—L. alesi, 2—L. aureomontis, 3—L. brevimacula, 4—L. cala, 5—L. chujoi, 6—L. davidiana, 7—L. elongata, 8—L. fikaceki, 9—L. flavopunctata, 10—L. hajeki, 11—L. jaechi, 12—L. lignipisces, 13—L. miragricola, 14—L. mollis, 15—L. nivalis, 16—L. obesa, 17—L. obliquonotata, 18—L. qinlingmontis, 19—L. ruficollis, 20—L. ruzickai, 21—L. schoenmanni, 22—L. smetanai, 23—L. tonitrumontis, 24—L. yunnanicola.