Tachinus (Tachinoderus) lobutulus Chang, Li & Yin, new species

Chinese Common Name: 小叶圆胸隐翅虫

(Figs 6–7, 12)

Type material ( 10 exs). Holotype: CHINA: Ƌ: ‘ China: Yunnan Prov., Xishuangbanna (西双版纳), Menglun Town (勐仑镇), Ba-ka-xiao-zhai (巴卡小寨), 21°58’00’’N, 101°12’01’’E, alt. 800 m, 31.iii.2018, sifting, Peng,

Shen & Cheng leg.’ (SNUC); Paratypes: CHINA: 1 ♀: ‘ China: Nanban Village, Nabanhe conv., Yunnan Prov., 7.i.2004 , Li & Tang leg.’; 1 ♂: same label data, except ‘alt. 700 m, 26.vii.2005, Li & Li leg.’; 1 ♀: same label data, except ‘N22.10.032, E100.39.359, alt. 720 m, 22.xi.2008, Hu Jia-Yao & Yin Zi-Wei leg.’; 1 ♂: same label data, except ‘ 06.v.2009, Hu Jia-Yao & Tang Liang leg.’; 1 ♂, 1 ♀: ‘ China: Yunnan Prov., Nanbanhe N. R. (纳版河自然 保护区), Manfei (曼费), N22.09.593, E100.41.327, alt. 660 m, 18.xi.2008 , Hu Jia-Yao & Tang Liang leg.’; 1 ♂, 1 ♀: also from Manfei, except ‘alt. 700 m, 05.v.2009 , Jia-Yao Hu & Zi-Wei Yin leg.’; 1 ♀: also from Manfei, except ‘ 9.i.2004 , Li & Tang leg.’(all in SNUC).

Diagnostic description. Male. Habitus as in Fig. 6A; TBL 3.39–4.0 mm, FBL 2.21–2.64 mm; head black, pronotal disc, elytra, abdomen and posterior tibiae darkish-brown, antennomeres I, XI, mouthparts, pronotal posterolateral areas, and most parts of legs yellowish-brown. Head sub-triangular, HL 0.42–0.61 mm, HW 0.52– 0.75 mm, with microsculpture at posterior portion; eyes prominent, EyL 0.19–0.24 mm; antenna elongate, AnL 2.17–2.26 mm, relative lengths of antennomeres I–XI: 1.25: 1: 1.5: 1.5: 1.5: 1.5: 1.5: 1.5: 1.25: 1.25: 1.75. Pronotum strongly transverse, PL 0.7 5– 0.84 mm, PW 1.32–1.41 mm, PI = 0.57–0.60. Elytra slightly broader than long, EL 1.08–1.22 mm, EW 1.18–1.27 mm, EI = 0.92–0.96. Abdominal surface with microsculpture consisting of transverse waves; tergite VIII (Fig. 7A) with four short lobes, inner lobes longer than outer ones; sternite VII (Fig. 7B) triangularly emarginate at middle along posterior margin, granules densely arranged along midline at posterior half; sternite VIII (Fig. 7C) with two lobes, deeply incised in between, median length of sternite 0.82 times as long as depth. Length of aedeagus (Fig. 7 D–E) 0.75 mm, parameres short and broad, below level of apex of median lobe, slightly curved ventrally in lateral view; apex of median lobe triangular in ventral view.

Female. General habitus (Fig. 6B) similar to male. Measurements: TBL 3.44–4.14 mm, FBL 2.36–2.64 mm, HL 0.42–0.57 mm, HW 0.75–0.80 mm, EyL 0.19–0.24 mm, AnL 2.17–2.21 mm, PL 0.71–0.80 mm, PW 1.32–1.41 mm, PI 0.53–0.57, EL 1.13–1.18 mm, EW 1.32–1.41 mm, EI 0.83–0.86. Tergite VIII (Fig. 7F) with four lobes, outer lobes much longer than inner ones, shallowly incised between inner lobes; sternite VIII (Fig. 7G) with six lobes, fimbriate lobes longer than others.

Comparative notes. Tachinus lobutulus is similar to T. bilobus and T. longicornis in sharing short and broad parameres of the aedeagus. From T. bilobus, the new species can be separated by the relatively much less elongate male tergite VIII, and inner lobes of female tergite VIII being much shorter than outer ones. From T. longicornis, the new species differs in the male sternite VIII with only two lobes, and apices of the parameres not exceeding the median lobe of the aedeagus.

Distribution. China: Yunnan (Fig. 12).

Etymology. The new specific epithet refers to the short inner lobes of female tergite VIII.