Tianzhuaphaenops jinshanensis, Zhao, Danyang & Tian, Mingyi, 2016

Zhao, Danyang & Tian, Mingyi, 2016, A new genus and species of troglobitic ground beetle from eastern Guizhou, Southwest China (Coleoptera: Carabidae: Trechinae), Zootaxa 4097 (3), pp. 434-441 : 437-440

Tianzhuaphaenops jinshanensis n. sp.

( Figures 1–4 )

Material. Holotype male, Cave Jinshan Rongdong, Luihe Vallige, Bangdong Town, Tianzhu County, Qiandongnan Miao and Dong Autonomous Prefecture, Guizhou Province, 26°57'42" N / 109°12'24" E, 460 m, VIII-21-2015, Mingyi Tian & Jingli Cheng leg., deposited in the insect collections of South China Agricultural University, Guangzhou ( SCAU); paratypes: 3 males and 6 females, ibid., in SCAU.

Length: 6.0– 6.1 mm (including mandibles), or 5.4–5.6 mm (excluding mandibles); width: 1.0– 1.2 mm. Habitus as in Fig. 1 .

Description. The whole body is yellowish brown. Head glabrous on upper surface and gula. Underside of head, pro- and metasterna, legs, antennae and ventrites pubescent. Genae and disc of pronotum are covered with sparse hairs which are much longer on pronotum than on the genae. Elytra is covered with denser and minute pubescence. Microsculptural engraved meshes moderately transverse.

Body elongated, fore body, including mandibles, are distinctly shorter than elytra.

Head semi-aphaenopsoid, strongly elongated, distinctly longer than wide, HLm/HW=2.29–2.31, HLl/ HW=1.73–1.74. Widest at about basal 2/5ths of head from labrum. Genae gently expanded. Supra-orbital furrows incomplete, nearly parallel-sided anteriorly, effaced at the level of the widest point, distinctly divergent posteriad. Anterior supra-orbital pore located at middle of head (from labrum), posterior one at about 1/4th of head from base, distance between anterior and posterior pores shorter than that between both anterior ones. Frons and vertex moderately convex. Clypeus quadrate, 4-setose. Labrum transverse, widely but shallowly emarginated at front margin, 6-setose. Mandibles moderately developed, gently unciform at apex. Mentum distinctly concave at base, without pits. Palps fairly slender, subcylindrical, 3rd and 4th maxillary palps glabrous, subequal in length; 2nd labial palp distinctly longer than 3rd, with two setae on inner margin, and 2–3 additional ones in subapical part, 3rd palpomere glabrous. A pair of suborbital pores on ventral side, between submentum and neck. Antennae slender, 1st antennomere thick, slightly shorter than 2nd, which is about 0.6 times as long as 3rd; 4th and 5th antenomeres longest, nearly twice as long as 2nd; gradually shortened from 6th to 10th which is subequal to 11th.

Pronotum distinctly shorter than head, PL/HLm=0.58–0.59, PL/HLl=0.77–0.78, but wider than head, PW/ HW=1.21–1.22. Longer than wide, PL/PW=1.14, widest at about 1/4th from apex, gently narrowed both distad and basad, more constricted before hind angles, but not sinuated. Sides finely beaded. Front angles acute, albeit hind ones angulate and nearly rectangular; anterior lateromarginal setae just before widest point, posterior ones a little before hind angles. Base slightly narrower than front, PfW/PbW=1.13, the former is nearly straight, while the latter slightly emarginated. Disc convex, middle line deep, connected to both front and basal impressions which are welldefined.

Scutellum short and narrow. Elytra fairly long and elongate ovate, much longer than wide, EL/EW=1.87–1.89, distinctly longer than fore body, widest at middle. Lateral margins subserrate and ciliate throughout. Humeral angles obtuse. Base unbordered; disc convex, but distinctly depressed near base. Striae well-defined, punctuate, intervals fairly convex. Anterior and posterior dorsal pores situated on 3rd stria, at about 2/7ths and 4/7ths of elytra from base respectively, preapical setiferous pore located exactly on junction point of 2nd and 3rd striae, at about 1/10th of elytra from apex, much closer to suture than to apex of elytra. Basal pores located near base, along both sides of scutellum. Humeral set of marginal umbilicate pores not aggregated, only 2nd pore close to marginal gutter, 4th distant from 3rd. Both 5th and 6th pores of the middle set close to each other, located at about middle of elytra.

Legs thin and fairly long, femora moderate, tibiae not longitudinally furrowed, hind tibia distinctly longer than elytral width; protarsi short; 1st tarsomere shorter than, subequal to, and longer than 2nd–4th tarsomeres combined in pro-, meso- and metatarsi, respectively.

Male genitalia ( Figs. 2 ): Median lobe of aedeagus very thin and fairly long, well-sclerotized, with a large sagittal aileron and a fairly large and elongate copulatory piece; parameres thin, much shorter than median lobe.

Etymology. Indicates the type locality of this new species.

Distribution. China (Guizhou). Known only from the limestone cave Jinshan Rongdong, in Easternmost Guizhou ( Fig. 3 ).

Jinshan Rongdong ( Figs. 4 ) is a beautiful show cave. It is open at bottom of the Southern slope of Mt. Jinfeng, about eight kilometers away from the main town of Tianzhu County. It is 7200 meters long and contains a 3400 meters long underground river. The beetles were collected in dark zones in the first chamber that is about 50 to 60 meters from the entrance. They were wandering on the floor or on the wall.

Figures

FIGURE 1. Habitus of Tianzhuaphaenops jinshanensis n. gen., n. sp., male, holotype (chaetotaxy indicated by white points)

FIGURE 2. Male genitalia of Tianzhuaphaenops jinshanensis n. gen., n. sp. (a. median lobe and parameres, lateral view; b. median lobe, dorsal view)

FIGURE 3. Distribution of Tianzhuaphaenops jinshanensis n. gen., n. sp.

FIGURE 4. Cave Jinshan Rongdong (a. and b. entrance and gate; c. underground river; d. a chamber to show where the beetles were collected; e. an active beetle in cave)