Qianotrechus congcongae Tian & Zhao, 2021

Tian, Mingyi, Huang, Sunbin, Jia, Xinyang & Zhao, Yi, 2021, Two new genera and three new species of cavernicolous trechines from the western Wuling Mountains, China (Coleoptera, Carabidae, Trechinae), ZooKeys 1059, pp. 57-78 : 57

Qianotrechus congcongae Tian & Zhao sp. nov.

Figures 1 , 3B, E , 6 , 7 , 8

Type material.

Holotype male, cave Shigao Dong , Hexi, Nanchuan, Chongqing, 28.82° N, 107.32°E, 729 m, 2021-IV-13, leg. Yi Zhao, Xinyang Jia and Mingyi Tian, in SCAU.

Diagnosis.

A small, stout cave trechine, semi-aphaenopsian, with a brown body, rather short appendages and broadly tumid prothorax.

Description.

Length: 5.5-5.8 mm, width: 1.9 mm. Habitus as in Figure 6 .

Body brown, palps, antennae and tarsi yellow. Surface and underside smooth and glabrous. Microsculpture: isodiametric meshes on head, transversal meshes or striate on pronotum and elytra.

Head (Figs 3B , 6 ) moderately elongate, longer than wide excluding mandibles, HLl/HW = 1.4; genae moderately convex, widest near head mid-length; frons and vertex moderately convex; frontal furrows nearly parallel-sided, but slightly and shortly convergent posteriorly, ending at widest point of head; anterior and posterior supraorbital pores present, located at about middle and basal 1/5 of head excluding mandibles; clypeus 4-setose, labrum transverse, faintly bisinuate at the front margin, 6-setose; right mandibular teeth bidentate; mentum completely fused with submentum, 2-setose, tooth short and pointed at apex, much shorter than the lateral lobes; ligula fused with paraglossae, 8-setose at apex; palps thin and slender, the 2nd labial palpomere about 0.9 times as long as 3rd; 3rd maxillary palpomere as long as 4th; suborbital pores close to neck; antennae thin, filiform, extending to about middle of elytra; 3rd antennomere longest, about twice as long as scape; relative length of each antennomere compared with scape in the holotype as follows: 1st (1.0), 2nd (1.1), 3rd (1.9), 4th (1.7), 5th (1.6), 6th (1.4), 7th (1.2), 8th (1.2), 9th (1.0), 10th (1.0) and 11th (1. 4).

Prothorax quadrate, as long as wide, widest behind middle; as long as head excluding mandibles, as wide as pronotum (Fig. 7A ). Pronotum slightly wider than head, PnW/HW = 1.2, widest at about apical 1/4, lateral margins finely bordered throughout, suddenly narrowed before hind angles; base and front unbordered, the former narrower than the latter; anterior latero-marginal pores located at apical 1/5 and the posterior pores in front of hind angles. Scutellum small.

Elytra (Fig. 6 , 3E ) stout, longer than wide, EL/EW = 1.6, wider than pronotum, EW/PW = 2.1, and much longer than fore body including mandibles; lateral margins ciliate throughout; disc strongly convex, striae shallow, easily traceable though more or less reduced, intervals flat; anterior and posterior dorsal pores of the 3rd striae at about basal 1/6 and middle of elytra, respectively, preapical pore at about apical 1/7 of elytra, much closer to elytral suture than to apical margin; only an apical pore present, the anguloapical pore absent.

Legs moderately long and densely pubescent; fore and middle tibiae longitudinally grooved externally, whereas simple in hind tibiae; the 1st and 2nd protarsomeres dilated and spurred inwards at apex in male.

Ventrites IV-VI, each with a pair of paramedial setae, ventrite VII bisetose in male. Male genitalia (Fig. 7C, D ): median lobe of aedeagus well-sclerotised, long, and elongate, slightly arcuate at median portion, gradually narrowed toward apex which is bluntly obtuse; basal opening large, with a large sagittal aileron; inner sac provided with a thick and long copulatory piece which is about 2/9 as long as aedeagus; in dorsal view, apical lobe longer than wide, gradually narrowed toward apex which is broadly rounded; parameres well developed, shorter than median lobe, each armed with 4 and 5 long setae at apex.

Female. unknown.

Remarks.

The genus Qianotrechus Uéno, 2000 is comprised of three semi-aphaenosian trechine species and one subspecies (Fig. 1 ): Q. magnicollis Uéno, 2000, Q. tenuicollis tenuicollis Uéno, 2000, and Q. tenuicollis cheni Uéno, 2003 from Suiyang County and Q. laevis Uéno, 2000 from Zheng’an County, Zunyi Shi, Guizhou Province ( Uéno 2000, 2003). Another species, Q. fani Uéno, 2003, has been reported from Gulin County, Luzhou Shi, Sichuan Province, but it is not a Qianotrechus and so has been transferred into the genus Uenoaphaenops Tian & He, 2020 ( Tian and He 2020).

Qianotrechus congcongae sp. nov. is closely similar to Q. laevis from Zheng’an County of northeastern Guizhou Province ( Uéno 2000). The locality of the latter species (Mawan Dong) is about 30 km in a straight line from Shigao Dong in Nanchuan, Chongqing. However, Q. congcongae is different from Q. laevis in having a stouter body (more elongated in Q. laevis ), a broader prothorax with propleura widely visible from above (narrowly visible in Q. laevis ) (Fig. 7A, B ), and the pronotum evidently narrowed near the base, which is distinctly sinuate before posterior latero-marginal setae (only slightly sinuate in Q. laevis ). In addition, the median lobe of the aedeagus is straight and widened at apex (slightly sinuate and narrowed in Q. laevis ) (Fig. 7C-F ).

Etymology.

The name of this beautiful species is in honour of "Xiao Cong", a nickname of Ms Jia Liu, an outstanding and leading caver in the Chongqing Cave Exploration Team, Chongqing, for her kind assistance in our collecting trips in Chongqing.

Distribution.

China (Chongqing). Known only from the limestone cave in Shigao Dong, Nanchuan (Fig. 1 ). Shigao Dong is located about 0.5 km from Hexi Zhen (Nanchuan) in a straight line to the south. The cave, which is near a small road and just behind a farm house, has a large entrance (Fig. 8A ). There is an underground river inside the cave. The main passage is about 100 m from the entrance. At first, we reached as far as 300 m along the right passage of the case, which is huge, several dozen metres high and wide (Fig. 8B ), but without any finding specimens. Later, we came back to the cave and went explored the left passage, where we observed two beetles running on the wet ground near a small pool, about 160 m from the cave’s entrance (Fig. 8C, E ). Apart from Qianotrechus congcongae sp. nov., three species of millipedes, a dipluran, and a troglophilic frog ( Oreolalax rhodostigmatus Hu & Fei, 1979) were also observed in this cave (Fig. 8D ).

Figures

Figure 1. A distribution map showing the localities of the three surveyed caves (stars) and the known species and subspecies of the genus Qianotrechus Ueno, 2000 (dots) A Shigao Dong B Qiankou Dong C Qianlong Dong.

Figure 3. Ventral head (A-C) and elytral chaetotaxy (E, F) of cave beetles A, D Wulongius qilinger gen. nov. and sp. nov. B, E Qianotrechus congcongae sp. nov. C, F Qianlongius zhoui gen. nov. and sp. nov.).

Figure 6. Qianotrechus congcongae sp. nov., habitus, holotype male.

Figure 7. Pronotum and male genitalia of Qianotrechus species. A, C, E Q. congcongae sp. nov. B, D, F Q. laevis Ueno, 2000 A, B pronotum C, E median lobe and parameres, lateral view D, F apical lobe, dorsal view.

Figure 8. Cave Shigao Dong. A entrance B the huge passage C place where the two beetles were discovered D a frog, Oreolalax rhodostigmatus Hu & Fei, 1979 E a running individual of Qianotrechus congcongae sp. nov.