Tachinus (Tachinoderus) flavimaculatus Feng & Yin, 2021

Feng, Yong-Yan & Yin, Zi-Wei, 2021, Tachinus flavimaculatus, a new species of the subgenus Tachinoderus Motschulsky from China (Coleoptera: Staphylinidae: Tachyporinae), Zootaxa 5039 (1), pp. 129-133 : 129-132

Tachinus (Tachinoderus) flavimaculatus Feng & Yin , sp. nov.

Chinese Common Name: 浅Ṅ圆⁂aeffiffl

( Figs 1–2 )

Type material. Holotype: CHINA: ♂: ‘China: Xizang, Linzhi City , Motuo Co. ( ḄȒ 县), 96K, nr. Gon’ri Vill. (Ḱ H村), 1400 m, FIT, 17-21.iii.2017, Song, Bi, Yang leg.’ ( SNUC) . Paratypes: CHINA: 1 ♂, 1 ♀: same label data as of holotype ; 2 ♂♂: ‘ China: Xizang, Linzhi City , Pailong Co. ( ẆAE 县), 30°0’34.71”N, 94°57’57.64”E, 2190 m, FIT, 15.vii.-01.viii.2019, Zi-Wei Yin leg. ’; 4 ♂♂: ‘ China: Xizang, Bomi Co. (波Ẋ县), Yigong Town (BḰ县9), 30°17’16.25”N, 94°44’42.32”E, 2300 m, leaf litter, 20.vii.2019, Zi-Wei Yin leg.’ (all in SNUC) .

Diagnostic description. Male. Habitus as in Fig. 1A ; total body length (from clypeal anterior margin to apex of abdomen) 3.19–3.80 mm, fore body length (from clypeal anterior margin to apex of elytra) 2.18–2.45 mm; head, pronotal disc, elytra and abdomen black, antennomeres 3–10, and most parts of legs darkish-brown, antennomeres 1, 2, and 11, mouthparts, sides and posterior margin of pronotum, shoulder of elytra and tarsi yellowish-brown. Head sub-triangular, length (from anterior margin of clypeus to anterior margin of pronotum, excluding area covered by pronotum) 0.54–0.58 mm, width across eyes 0.66–0.70 mm, with fine and sparse punctures, with microsculpture posterior to eyes and at base; eyes prominent, longitudinal length 0.19 mm; antennae elongate, length 1.20–1.25 mm, relative lengths of antennomeres 1–11: 1.75: 1.13: 1.50: 1.0: 1.38: 1.25: 1.38: 1.38: 1.38: 1.13: 2.0. Pronotum strongly transverse, length along midline 0.75–0.83 mm, maximum width 1.17–1.31 mm, length/width 0.63–0.64, surface with punctures as of head, without microsculpture. Elytra slightly transverse, length along suture (excluding scutellum) 0.96–1.05 mm, maximum width 1.22–1.34 mm, length/width 0.78, with shallow and sparse punctures that are larger than those of pronotum, lacking microsculpture. Surface of abdomen lacking pruinose spots, with punctures more distinct than those of elytra and dense microsculpture consisting of transverse waves between punctures (tergites III–VII); tergite VIII ( Fig. 2A ) with four moderately long lobes, inner lobes much longer than outer ones; sternite VII ( Fig. 2B ) with posterior margin roundly and deeply emarginate, granules evenly arranged in row at middle along posterior margin, others sparsely arranged in oval area; sternite VIII ( Fig. 2C ) with four lobes, deeply incised between inner lobes, median length of sternite 0.78 times as long as depth of incision. Length of aedeagus ( Fig. 2D, E ) 0.70 mm, median lobe broad at base and narrowing toward apex, evenly curved ventrally, parameres elongate and broadened before apices, almost straight in dorso-ventral view.

Female. General habitus ( Fig. 1B ) similar to male. Measurements (as for male): total body length 3.26 mm, fore body length 2.15 mm, length of head 0.56 mm, width 0.66 mm, length of eye 0.19 mm, length of antenna 1.19 mm, length of pronotum 0.71 mm, width 1.11 mm, length/width 0.64, length of elytra 0.95 mm, width 1.18 mm, length/ width 0.81. Tergite VIII ( Fig. 2F ) with four lobes, inner lobes slightly longer than outer ones, incision between inner lobes V-shaped, sternite VIII ( Fig. 2G ) with six lobes, fimbriate lobes longer and broader than others.

Comparative notes. Tachinus flavimaculatus sp. nov. shares with T. rimosus Ullrich from central Nepal and T. sugayai Schülke distributed in eastern and southern China a similar general appearance, and the shoulders of the elytra bearing a pair of light maculae ( Ullrich 1975; Schülke 2003). From T. rimosus the new species can be readily separated by the complete lack of pruinose spots on tergites III–V, relatively shorter median lobe of the aedeagus, and much deeper median emargination and incision of male sternite VII and female tergite VIII, respectively; from T. sugayai the new species differs in the darker color of the body, much sparser granules of male sternite VII, dorso-ventrally less curved parameres of the aedeagus, and female tergite VIII with four lobes (inner two lobes merged into a single plate in T. sugayai ). Prior to the present study, only one species of the T. nepalensis group, i.e., T. bimorphus Chang, Li, Yin & Schülke , has been known from Xizang ( Chang et al. 2019). Tachinus bimorphus has yellow antennomeres 10–11, the sides of the elytra are slightly narrowing toward apex from apical third, the punctation of elytral disc is much more distinct, and the shapes of the aedeagus and female tergite are of totally different shapes.

Distribution. China: Xizang.

Etymology. The new specific epithet is a Latin participle combined from flâvus (- a, - um), meaning ‘yellow, golden’, and maculâtus (- a, - um), meaning ‘stained, spotted’. The name refers to the light-yellow maculae of the elytral shoulders.

Figures

FIGURE 1. Habitus of Tachinus flavimaculatus sp. nov. A. Male. B. Female. Scale bars: 0.5 mm.

FIGURE 2. Diagnostic features of Tachinus flavimaculatus sp. nov. (A–E. Male. F, G. Female). A, F. Tergite VIII. B. Sternite VII. C, G. Sternite VIII. D, E. Aedeagus, in ventral (D) and lateral (E) view. Scale bars: 0.2 mm.