﻿A contribution to the knowledge of cave-adapted ground beetles from Guiyang, central Guizhou Province, southwestern China (Coleoptera, Carabidae, Trechini)

﻿Abstract A new genus and two new species of cavernicolous trechines are reported from central Guizhou Province, southwestern China. Haixiaphaenopsgen. nov. is established to place a new species discovered in two limestone caves in northern Qingzhen Shi: H.jinxiaohongaesp. nov. (Dawan Dong cave and Changtu Dong and Dawan Dong caves). This new genus is allied to Zhijinaphaenops Uéno & Ran, 2002. Zhijinaphaenopszhaofeiisp. nov. is described from Zhangkou Dong cave in northern Jiuzhuang Zhen of Xifeng County. In addition, two new localities of the species Zhijinaphaenopsjingliae Deuve & Tian, 2015, and two new localities of SinaphaenopschengguangyuaniMa et al. 2020 are provided. A distribution map for all cavernicolous trechine beetles known in Guiyang is provided.


Introduction
Undoubtedly, Guizhou is the province harbouring the richest cave specific diversity in China in terms of hypogean trechine beetles (Tian et al. 2016Chen et al. 2017;Huang et al. 2020;Tian et al. 2021). Of the 168 cave species of trechines known in China, 62 are occurring in Guizhou Province. But the subterranean fauna of ground beetles is poorly studied in Guiyang Shi, central Guizhou. Only three species in two genera of cave-adapted trechines have been reported from this area. The genus Zhijinaphaenops Uéno & Ran, 2002 was formerly described from Zhijin County, Bijie Shi, central Guizhou, then reported from several other counties, viz. Dafang, Xifeng, Zunyi, and Weng'an. Nine species are included in the genus so far (Uéno and Ran 2002;Tian 2015, 2018). Among them, two species were recorded from Xifeng County, Guiyang Shi: Zhijinaphaenops jingliae Tian, 2015 andZ. liuae Deuve &Tian, 2015.
Led by Guangyuan Cheng, the second author, the local cavers from the Haixia Caving (a cave exploration team in Guiyang) have begun to carry out biological surveys in recent years. They have visited many limestone caves in central Guizhou Province and discovered some interesting cavernicolous ground beetles (Fig. 1). For instance, Sinaphaenops chengguangyuani Ma et al. 2020 was formerly found by them in a limestone cave in Longli County of Qiannan Buyi & Maio Autonomous Prefecture, close to Guiyang . Two more localities, from Guiyang and Longli respectively, of this beautiful species are now confirmed. In Xifeng County, they discovered two other caves where Zhijinaphaenops jingliae is living. In Qingzhen Shi, they found two beetle individuals in the cave Dawan Dong and another beetle in the cave Changtu Dong. These beetles are members of an undescribed species belonging to an unknown genus allied to Zhijinaphaenops.
Hence, we establish a new genus to accommodate the new species found in the caves Dawan Dong and Changtu Dong, describe a new Zhijinaphaenops species from the cave Zhangkou Dong in Xifeng County and provide new localities for Zhijinaphaenops jingliae and Sinaphaenops chengguangyuani in the suburbs of Guiyang, the capital city of Guizhou Province.

Materials and methods
The beetle specimens were collected in caves by hand or by using an aspirator, and kept in vials with 50% ethanol. One exemplar of each species was placed into 95% ethanol for DNA sequencing. Dissections and observations were made by using a Leica MZ75 dissecting stereomicroscope (Wetzlar, Germany). Dissected genitalia, including the median lobe and parameres of aedeagus, were glued on small transparent plastic cards and pinned under the specimen from which they were removed. Digital pictures were taken using a Canon EOS 5D Mark III camera (Tokyo, Japan), and then processed by means of Adobe Photoshop CS5 software (Adobe System Incorporated, California, USA).
Measurements and terminologies used in the text follow Tian et al. (2016). The abbreviations used in the text are as follow: HLm length of head including mandibles, from apex of right mandible to occipital suture; HLl length of head excluding mandibles, from front of labrum to occipital suture; HW maximum width of head; PrL length of prothorax, along the median line; PnL length of pronotum, as above; PrW maximum width of prothorax; PnW maximum width of pronotum; PfW width of pronotum at front; PbW width of pronotum at base; EL length of elytra, from base of scutellum to elytral apex; EW maximum width of combined elytra.
All material is deposited in the insects collection of South China Agricultural University, Guangzhou, China (SCAU).
Remarks. Haixiaphaenops gen. nov. is allied to the genus Zhijinaphaenops Uéno & Ran, 2002 by sharing the following characteristics: (1) mentum and submentum completely fused; (2) prothorax strongly dilated and propleura notably visible from above, pronotum with only anterior latero-marginal setae; (3) only protarsomere 1 modified in male, which is long and inwardly spurred at apex; (4) pronotum covered with long setae; (5) elytra shortly pubescent, with hardly distinguishable striae, and the 1 st marginal umbilicate pore inwardly and backwardly shifted, located behind the level of the 3 rd pore. However, Haixiaphaenops gen. nov. readily differs from Zhijinaphaenops in several generic-level characters, such as: (1) 2 pairs of frontal pores present in Haixiaphaenops gen. nov., versus only the posterior pores present in Zhijinaphaenops; (2) antennae much shorter in Haixiaphaenops gen. nov., only extending at most to apical 1/4 of elytra, versus longer, projection over apices of elytra in Zhijinaphaenops; (3) pronotum elongated quadrate, nearly parallel-sided in Haixiaphaenops gen. nov., versus subcordate, not parallel-sided in Zhijinaphaenops; (4) elytra much stouter and more convex in Haixiaphaenops gen. nov., partly concealing lateral margins in median portion, versus more elongated and less convex in Zhijinaphaenops, with whole lateral margins visible from above; (5) base of elytra bordered in Haixiaphaenops gen. nov., versus unbordered in Zhijinaphaenops; and (6) male genitalia are small and stout, slightly bent medially, and widely rounded at apex in Haixiaphaenops gen. nov., versus large and slender, strongly arcuate medially, and more or less sharpened at apex in Zhijinaphaenops.
Ventrites IV with a pair, V-VI each with two pairs of paramedial setae, VII 6-setose apically in male.
Male genitalia (Fig. 5): Median lobe of aedeagus short and stout, moderately sclerotized, with a large sagittal aileron and a large and elongated copulatory piece; ventral margin hardly sinuate, base opening wide, apex broadly rounded; parameres long and broad, but shorter than median lobe, each with four long setae at apex; in dorsal view, apical lobe rounded at apex, nearly as long as wide.
Female: unknown. Etymology. This species is dedicated to Ms Xiaohong Jin, an active member of Haixia Caving, Guiyang, who found and collected the unique known specimen.
Variations. Both of the paratype specimens have a slightly thinner head than the holotype, and whole body concolorous brown instead of dark brown. Presently, we deal  with the differences as individual variations regarding the facts that the similarities of morphological and genital structures, and the caves Dawan Dong and Changtu Dong are close to each other. Molecular analysis would be helpful to clarify their relationship.
Located in the northern most part of Qingzhen Shi, about 45 km from the main town, Dawan Dong (Fig. 6A) in openings of a cliff of the Maotiaohe valley, on the western side of the river (Fig. 6B). This beautiful cave is 2026 m long, 10-30 m wide and 10-50 m high (Zhao Fei, pers. comm.), with large galleries and several huge chambers (Fig. 6C, D). The single specimen was found running on the ground in a moist and dark area about 500 m from the entrance (Fig. 6 E). Other cave invertebrates found in this cave were woodlice, harvestmen and crickets.
Cave Changtu Dong (Fig. 7) is located about 3.5 km from Dawan Dong in the west, and about half a kilometre from Ximi Village. The cave has two entrances, its length is still unknown. It has been badly impacted and not so pristine as Dawan Dong. Most of the main passage from the smaller entrance is wet and favourable for cave fauna (Fig. 7A, B). The single specimen of H. jinxiaohongae gen. nov., sp. nov. was collected together with harvestmen, moths, and millipedes of the genera Pacidesmus and Glyphiulus along the main passage ( Fig. 7C-G).
Body reddish brown, palps and tarsi pale. Head covered with sparse and short hairs, whole disc of pronotum covered with dense and long setae; elytra densely pubescent, except glabrous at apical portion; genae, ventral head and prosternum with a few setae; meso-and metasterna and hind coxae dense setose; abdominal ventrites covered with dense and short pubescence.
Microsculptural engraved meshes isodiametric on labrum and base of frons, moderately transverse on vertex and more or less transversally striate on pronotum and elytra. Elytra rather stout, fore body (including mandibles) as long as elytra.
Legs rather long for a Zhijinaphaenops species, fore and middle tibiae longitudinally furrowed; the 1 st protarsomere in male elongated and widened, denticulate on inner side of apex; 1 st tarsomere as long as 2 nd -4 th tarsomeres combined in all legs.
Male genitalia (Fig. 10A, B): Median lobe of aedeagus short, moderately sclerotized, with a large sagittal aileron and a large and elongated copulatory piece which is about 1/4 of median lobe in length; ventral margin strongly sinuate, then tapering toward apex which is blunt; base opening rather narrow, apical lobe narrow, much longer than wide, broadly rounded at apex; parameres long and broadly widened, but shorter than median lobe, each with 3 long setae at apex.
Remarks. Similar to Zhijinaphaenops jingliae Deuve & Tian, 2015, but Z. zhaofeii sp. nov. differs in having a wider head, with labrum bisinuate instead of nearly straight, mandibles less hooked at tips and a median lobe with a broader apex in dorsal view.
Etymology. In honor of Mr Fei Zhao, a young active caver in Guiyang. Distribution. China (Guizhou). Known only from limestone cave Zhangkou Dong, in the suburb of Guiyang (Fig. 1).
Located in the northwestern part of Xifeng County, Zhangkou Dong (Fig. 11) on the southern bank of the Wujiang River. The entrance (Fig. 11A) is close to the main road from Jiuzhuang town to the dock. The passage goes obliquely down to the inner part of the cave, with a small creek inside. It is a rather beautiful cave, but partly damaged by the villagers. The habitat remains favourable for cave animals (Fig. 11B, C). The single beetle was found under a stone in a muddy area about 100 m from the entrance (Fig. 11D). Other cave invertebrates found in this cave were millipedes of Pacidesmus and Glyphiulus (Fig. 11E, F), a mite (Fig. 11G), moths and crickets. Diagnosis. A medium-sized Zhijinaphaenops species, wholly brown and pubescent, head narrow, with thin and very long antennae which extend beyond of elytral apices. Habitus as in Figure 12 A.  Remarks. Zhijinaphaenops jingliae was recorded from Zhangkou Dong cave near Musa village, Shidong Zhen, Xifeng County (Deuve and Tian 2015). In 2020, this species was found in two caves of the same county, Mafen Dong (Xishan Zhen) and Wenquan Dong (Wenquan Zhen). Morphological characteristics including male genitalia of individuals from the above two caves are identical to the holotype specimen (Figs 9B-D, F-H, 10C, D).
Mafen Dong cave (Fig. 12B) is about 600 m from Mafen village, only 5 km away Zhangkou Dong cave in the east. The individuals of Z. jingliae were found running on the ground in a dark area not far from the entrance.
Wenquan Dong cave is near Xinglong village, about 30 km from Zhangkou Dong. It opens via quite large entrance in a small hill of a valley and is surrounded by bushes, (Fig. 13A). There are two large chambers inside and a main passage about two hundred meters long. There is a pool at the bottom of the first chamber. A large part of the cave is moist and maintains good conditions for cave animals (Fig. 13B, C). Apart from the single beetle of Zhijinaphaenops jingliae, other cave arthropod animals found in this cave were spiders and crickets (Fig. 13D-F). Distribution. China (Guizhou). Known from three limestone caves in Guiyang Shi and Longli County, Qiannan Buyi & Miao Autonomous Prefecture (Fig. 1).
Jianlong Dong cave (Fig. 14) is located at the eastern suburb of Guiyang, about 40 km from Shuijing Dong, the type locality of S. chengguangyuani. This cave is a municipal protected area because of the engraved inscriptions on the precipices inside dating from  the Ming Dynasty, over 400 years ago (Fig. 14A). The rather large entrance is just on the side of the road Jianlonglu (Fig. 14B). The cave is about 100 m long, with two chambers inside. The first half part is rather dry, then becomes wet in the inner part (Fig. 14C). All of the beetle individuals were collected in the inner part, running on the ground or on the wall. Other cave animals observed in this cave were millipedes (Glyphiulus sp., Fig.  14E), a snake (Elaphe mandarina Cantor, 1842; Fig. 14F), crickets and moths.
Duocai Dong is a stalagtite-rich cave, about 5 km from Shuijing Dong in straight line. The two individuals were collected in dark zone, running on the wall (Fig. 15).