Tachinus (Tachinoderus) bilobus Chang & Li & Yin & Schülke 2019, new species
Creators: name: Chang, Yuan
name: Li, Li-Zhen
name: Yin, Zi-Wei
name: Schülke, Michael
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Staphylinidae
Tachinus

description: Tachinus (Tachinoderus) bilobus Chang, Li & Yin, new species
Chinese Common Name: 双叶圆胸隐翅虫
(Figs 1–2, 12)
Type material (19 exs). Holotype: CHINA: Ƌ: ‘ China: Hubei Prov., Shennongjia (神农架), Muyu (木鱼), 6.viii.2002, Li & Tang leg.’ (SNUC). Paratypes: CHINA: 4 ƋƋ, 4 ♀♀: same label date as Holotype; 4 ♂♂, 1 ♀: ‘ China: Sichuan Prov., Chengdu, Qingcheng Mt. (青城山), 20.vii.2003, Li-Zhen Li leg.’; 1 ♂, 4 ♀♀: same label data, except ‘ 19.vii.2003, Hu & Tang leg.’ (all in SNUC).
Diagnostic description. Male. Habitus as in Fig. 1A; TBL 3.82–4.14 mm, FBL 2.36–2.68 mm; head, pronotal disc, elytra and abdomen black, antennomeres I–II, mouthparts, pronotal posterolateral areas and most parts of legs reddish-brown, tarsi yellowish-brown. Head sub-triangular, HL 0.33–0.42 mm, HW 0.75 mm, with microsculpture and finely punctures 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: 1.75: 1.5: 1.5: 1.5: 1.5: 1.25: 1.25: 1: 1.75. Pronotum strongly transverse, PL 0.80–0.85 mm, PW 1.37–1.46 mm, PI = 0.58–0.59. Elytra slightly transverse, EL 1.18– 1.27 mm, EW 1.37–1.41 mm, EI = 0.86–0.90. Abdominal surface with microsculpture consisting of transverse waves; tergite VIII (Fig. 2A) with four short lobes, inner lobes much longer than outer ones; sternite VII (Fig. 2B) shallowly and broadly emarginate at middle along posterior margin, granules evenly arranged in sub-triangular area; sternite VIII (Fig. 2C) with two lobes, deeply incised in between, median length of sternite 0.65 times as long as depth. Length of aedeagus (Fig. 2 D–E) 0.83 mm, parameres short and wide, each slightly angulate at apex in ventral view, slightly curved ventrally in lateral view.
Female. General habitus (Fig. 1B) similar to male. Measurements: TBL 4.00– 4.23 mm, FBL 2.64–2.82 mm, HL 0.38–0.47 mm, HW 0.80 mm, EyL 0.19 mm, AnL 2.12–2.26 mm, PL 0.85–0.89 mm, PW 1.37–1.55 mm, PI 0.57–0.58, EL 1.27–1.32 mm, EW 1.46–1.51 mm, EI 0.87–0.88. 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 than others.
Comparative notes. Tachinus bilobus is similar to T. lobutulus (described below) and T. longicornis Motschulsky in sharing a stout aedeagus with relatively broad parameres. Tachinus longicornis is readily distinguishable from both former species by the parameres of the aedeagus being distinctly exceeding apex of the median lobe, while T. bilobus differs from T. lobutulus in the female tergite VIII with the inner lobes being longer than the outer ones (the inner lobes are much shorter than outer lobes in T. lobutulus).
Distribution. China: Hubei, Sichuan (Fig. 12).
Etymology. The new specific epithet refers to the bi-lobed male sternite VIII.
description: Published as part of Chang, Yuan, Li, Li-Zhen, Yin, Zi-Wei & Schülke, Michael, 2019, A review of the Tachinus longicornis - group of the subgenus Tachinoderus Motschulsky (Coleoptera: Staphylinidae: Tachyporinae) from China, pp. 478-494 in Zootaxa 4545 (4) on pages 479-481, DOI: 10.11646/zootaxa.4545.4.2, http://zenodo.org/record/2618275