Miaotrechus heweii, Tian & Chen & Ma, 2020

Tian, Mingyi, Chen, Mengzhen & Ma, Zijun, 2020, A new anophthalmic trechine genus and two new species from southern Guizhou China (Coleoptera: Carabidae: Trechini), Zootaxa 4766 (4), pp. 575-587 : 581-585

Miaotrechus heweii n. sp.

( Figs. 1 , 4B , 8–11 )

Type material. Holotype: male, cave Jingua Dong , Jingua Dong Cun , Longquan Zhen, Danzhai Xian, Qiandongnan Miao & Buyi Autonomous Prefecture, Guizhou Province, China, 26.14059N ° / 107.80400°E, 732 m in altitude, 2019-X-4, leg. Jingli Cheng; paratypes: 2 males and 1 female, idem.

Description. Length: 4.5–5.0 mm; width: 1.5 mm. Habitus as in Fig. 8 .

Similar to M. mahua n. sp., but body slightly slenderer, and covered with pubescence instead of glabrous on upper side. Microsculpture meshes densely isodiametric on head, pronotum and elytra.

Head thinner, longer than wide (excluding mandibles), and longer than pronotum, HLl/HW = 1.15–1.24, HLm/ HW = 1.58–1.68, HLl/PL = 1.07–1.08; frons moderately convex, genae slightly expanded, widest at about 1/3 of head from labrum; anterior supraorbital pores located before widest portion. Antennae extending to about apical 1/4 of elytra, comparative length ratio of each antennomere in the holotype as: 1 st (1.0) / 2 nd (1.0) /3 rd (1.4) / 4 th (1.4) / 5 th (1.4) / 6 th (1.4) / 7 th (1.2) / 8 th (1.2) / 9 th (1.1) / 10 th (1.0) / 11 th (1.3).

Pronotum less expanded on apical portion, slightly transverse, PW/PL = 1.05, widest at about front fourth, lateral margins less bisinuate before hind angles than in M. mahua , hind angles also rectangular, front as wide as base; disc moderately convex, sparsely pubescent; basal foveae large and deep, basal transversal impressions wellmarked. Scutellum smaller than in M. mahua n. sp.

Elytra more elongated, amygdaloid, base more rounded, and apex narrower than in M. mahua . EL/(HLm+PL) = 1.23–1.27; EL/EW = 1.64–1.68, widest at about 3/7 of elytra from base, shoulders markedly rounded, lateral margins more expanded than in M. mahua , ciliate throughout instead of at basal half; discal surface strongly convex, pubescent; striae less evanescent than in M. mahua ; anterior discal pores of stria 3 backwardly shifted, at about basal fourth of elytra; only pore 2 of marginal umbilicate series close to marginal gutter, middle group (pores 5 and 6) widely spaced ( Fig. 4B ).

Legs slightly slenderer than in M. mahua ; protibia without longitudinal sulcus; tarsomere 1 much shorter than, as long as, and longer than 2–4 combined in fore, middle and hind legs respectively.

Male genitalia ( Fig. 9 ): The median lobe of aedeagus much longer than in M. mahua , strongly arcuate at median portion, apical portion largely bent ventrally and thinner; base large, sagittal aileron quite large and hyaline, inner sac armed with a short spooned copulatory piece, which is only fourth as long as aedeagus; in dorsal view, apical lobe gradually narrowed towards apex which is broader than in M. mahua ; parameres thin, each bearing only two long setae at apex.

Remarks. M. heweii n. sp. differs from the nominate species M. mahua n. sp. in many aspects: (1) Body thinner and wholly pubescent, vs. stout and glabrous in M. mahua ; (2) Antennae longer, extending at apical fourth of elytra, vs. at apical third in M. mahua ; (3) Lateral margins of elytra ciliated throughout, middle group of marginal umbilicate series widely spaced, vs. ciliated only on basal half, and middle group of marginal umbilicate series closely spaced in M. mahua ; (4) Hind tarsomere 1 more elongated, longer than tarsomeres 2–4 combined, vs. hind tarsomere 1 as long as tarsomeres 2–4 combined in M. mahua ; (5) protibia not sulcate, whereas sulcate in M. mahua ; and (6) Median lobe of aedeagus strongly arcuate, each paramere with two long apical setae, vs. median lobe nearly straight, only slightly arcuate near apex, and each paramere with 3 or 4 long apical setae in M. mahua .

Etymology. In honor of Prof. Wei He (Institute of Mountain Resources, Guizhou Academy of Sciences, Guiyang), a well-known speleologist in China.

Distribution. Guizhou (Danzhai). Known only from cave Jingua Dong ( Fig. 1 ).

Jingua Dong is a small but very beautiful cave which still retains natural conditions though it has been built by the local villagers for touristic purpose. All the specimens were collected in a small wet area under decayed wood debris inside the large chamber ( Figs. 10–11 ).

Figures

FIG. 1 Distribution of the genus Miaotrechus n. gen.

FIG. 4 Elytral chaetotaxy of Miaotrechus mahua n. sp. (A) and M. heweii n. sp. (B)

FIG. 8 Habitus of Miaotrechus heweii n. sp., holotype

FIG. 9 Male genitalia of Miaotrechus heweii n. sp. A. median lobe and parameres, lateral view; B. apical lobe of median lobe, dorsal view.

FIG. 10 Simplified map of Jingua Dong (courtesy of Wei He), the locality of Miaotrechus heweii n. sp., arrowhead showing the place where the type specimens were discovered.

FIG. 11 Cave Jingua Dong. A-C. beauties inside cave; D. an individual of Miaotrechus heweii n. sp.