Holotype: adult male (SCAU), China, Guizhou, Qianxinan Zizhizhou, Ceheng County, Rongdu Village, Cave Qiaoxia Dong, 24°03.008N, 105°43.147E, 964 m, 26.XII.2012, leg. Mingyi Tian, Weixin Liu, Feifei Sun & Haomin Yin. Paratypes. 1 male, 3 females, 10 juveniles (SCAU), same locality, together with holotype.

Length of adults of both sexes 46–55 mm, width of midbody segments 2.6–3.0 mm, body with 55–58 pleurotergites + telson. Holotype 46 mm long, 2.6 mm wide on midbody segment, maximum width on 6^th pleurotergite 3.5 mm, body with 57 pleurotergites + telson. Body coloration light yellow-brownish, anterior part of body slightly lighter. Metazonae slightly darker than prozonae, posterior margin of pleurotergites brownish to dark brown, more infuscate on anterior pleurotergites (Figs 1–7). Head yellowish, epicranial suture distinct, with a large, median, beak-shaped process located between antennae in males, below it densely and finely setose and granulate (Figs 1–2). Edges of genae, posterior margin of the head, and bases of antennae marbled light brown-yellowish. Labrum dark brown. Ocellaria composed of ca. 16–23, dark grey ocelli arranged in four irregular longitudinal rows (Fig. 2). Tömösváry’s organs about 2–3 times larger than an ocellus, placed between ocellaria and base of antenna. Antennae light yellow, rather long and slender, extending behind posterior edge of pleurotergite 6 in males or pleurotergite 3(4) in females when stretched backwards; antennomere length ratios: 2=3>4=5>6>1>7, antennomeres 5 and 6 with a small distodorsal field of fine setae (Fig. 16). Legs light yellow to yellow-brownish, tarsi much darker (Figs 1–7).

Figures 1–6. 

Paracortina zhangi sp. n. holotype 1 anterior body, subventral view 2 anterior body, sublateral view 3 midbody, ventral view 4 midbody, dorsal view 5 posterior body, ventral view 6 posterior body, dorsal view.

Figure 7. 

Paracortina zhangi sp. n. female paratype.

Collum much narrower than head, pleurotergite 6 in males strongly enlarged (Fig. 2). Prozonae delicately alveolate-areolate; fine longitudinal striations in front of stricture between prozonae and metazonae. Crests on collum normal, extended forwards from about midlength (Figs 1–2). All crests on the metazonae well-developed, forming 5+5 primary crests, 5+5 secondary crests, and 12–18 lower crests down to ventral pleurotergal edge (Figs 4, 6). 3^rd primary crest strongly enlarged. Ozopores starting with pleurotergite 6, present until penultimate pleurotergite, placed on tip of 3^rd primary crest (Figs 2, 4, 7). 2+2 primary and 3+3 secondary crests between poriferous crests. Pleurotergal setae 5+5, located at edges of primary crests; setal pattern as in Table 1. Axial line rather distinct (Figs 4, 6).

Male leg-pairs 1 and 2 much shorter, leg-pair 3 slightly shorter than following legs (Figs 1–2). Midbody legs about 4 (male) or 3 times (female) as long as pleurotergite height. Prefemora to a lesser extent, postfemora and tibiae more strongly, but still finely micropapillate ventrally (Fig. 15). Tarsi 1–3 only 1-segmented, from leg 4 to ultimate pair 2-segmented in both sexes; male tarsal pads visible from leg-pairs 3 to 23. All legs ending with a rather slender, long and curved claw (Figs 1, 2, 15). Coxal sacs present from leg 3 to 23. Male coxa 2 with a small anterior process and a posterior gonopore, the latter placed on a small cone. Coxa 7 with a long, subfalcate and apically pointed posterior (f), and a rather strong, pear-shaped anterior process (t) (Fig. 8); f in situ protruding between the gonopods. Coxae of remaining legs normal. Epiproct simple, with about 10 tuberculations in irregular rows (Fig. 6). Hypoproct tripartite, medial sclerite largest, subrectangular, bearing two paramedian macrosetae; each lateral sclerite with a single macroseta. Anal valves smooth, each divided into a small triangle and a large sclerite, both with a pair of macrosetae. Spinnerets comparatively thin and long, ending with a long macroseta (Fig. 5).

Figures 8–10. 

Paracortina zhangi sp. n. male paratype 8 leg-pair 7, anterior view 9 gonopods, dorsal view 10 gonopods, subventral view.

Gonopods (Figs 9–10, 17–18) yellow-brown to brown basally, seminal groove and telopodite black brown. Coxa with a large, curved, arch-shaped, anterior process (a) and a rather slender process (b), the latter a little more than half the length of telopodite. Prefemur with a large, clavate process (c) densely covered with long macrosetae. Femoroidal stem long, slender, rather clearly curved, directed cephalad. Telopodite’s terminal part twisted, with a large median (l), and a small lateral lobe (h). Solenomere (s) bifid, parasolenomere (ps) much shorter; seminal groove ending on the longer branch.

Female. Pleurotergites 2 and 3 greatly enlarged. Leg-pairs 1 and 3 with tarsal pads (Figs 11–12). Coxa 3 with a rather small process (m). Prefemora 3 and 4 relatively stout and clearly enlarged (Fig. 12). Leg-pair 2 (Fig. 13) rather strongly reduced down to a pairs of stout, apically shallowly biramous remnants in adult female (Fig. 7), normal in younger ones. Cyphopods small, densely setose, hidden in membranous sacs, divided laterally in the middle (Fig. 14). Coxae 7 normal, without processes.

Figures 11–14. 

Paracortina zhangi sp. n. female paratype 11 leg-pair 1, anterior view 12 leg-pair 3, posterior view 13 leg-pair 2, anterior view 14 cyphopod, lateral view.

Figures 15–18. 

Paracortina zhangi sp. n. male paratype 15 midbody leg, anterior view 16 antenna, lateral view 17 right gonopod, mesal view 18 right gonopod, lateral view.

The species is dedicated to the memory of Mr. Chongzhou Zhang for his contribution to the systematics of Diplopoda in China.

This species is distinguished from its congeners by the presence of 5+5 primary crests, 5+5 secondary crests on the metazonae, two processes on coxa 7 in males, and in certain specific characters of the male gonopods, as well as in the small process on coxa 3, and reduced leg-pair 2 in females.

China: Guizhou (Fig. 46).

The entrance of cave Qiaoxia Dong (Figs 19–22) is located under a bridge in the village of Rongdu. The cave is about 200 meters long, 10 meters wide and 5 meters high. It is rather polluted from sewage water and rubbish. Other animals living in this cave are the ubiquitous diplopod, Oxidus gracilis C. L. Koch, 1847 (Polydesmida, Paradoxosomatidae), some ground beetles, crickets (Fig. 19), glowworms (Fig. 20), and spiders, etc.

Figures 19–22. 

Cave Qiaoxia Dong 19–20 cave ceiling 21 cave deposits 22 P. zhangi sp. n. walking on a rock.

Holotype: adult male (SCAU), China, Guangxi, Baise City, Longlin County, Tianshengqiao Town, Yanchang Village, Cave I, 24.875732°N, 105.150143°E, 867 m, 12.VI.2014, leg. Mingyi Tian, Weixin Liu, Haomin Yin & Xiaozhu Luo. Paratypes. 2 males, 3 females, 2 juveniles (SCAU), same locality, together with holotype.

Length of adult males 39–52 mm, of adult females 47–55 mm. Width of midbody segments in adult males 2.2–2.6 mm, in adult females 2.5–3.0 mm. Body with 53–61 pleurotergites + telson. Holotype 44.0 mm long, 2.5 mm wide on midbody segments, maximum width on 6^th pleurotergite 2.5 mm, body with 54 pleurotergites + telson. Body coloration yellow-brownish. Metazonae slightly darker than prozonae, posterior margin of pleurotergites dark brown to brownish, more evidently so on the anterior pleurotergites (Figs 23–29). Head brownish to chocolate brown, epicranial suture distinct, with a slightly smaller, median, beak-shaped process located between antennae in males, surface below the vertex and genae densely beset with brown granules and fine setae (Fig. 23). Genae, labrum, the edge between the dorsal and the frontal face of head marbled dark brown. Ocellaria composed of ca. 21–32, dark grey ocelli arranged in four irregular longitudinal rows. Tömösváry’s organs about 4 times larger than an ocellus, placed between ocellaria and base of antenna (Fig. 23). Antennae brownish, tip of each antennomere infuscate; very long, extending behind posterior edge of pleurotergite 6 (male) or 4 (female) when stretched backwards (Figs 23, 29), antennomere length ratios: 2=3>4=5>6>1>7, antennomeres 5 and 6 with a small distodorsal field of fine setae (Fig. 39). Legs yellow-brownish to dark brownish, distal parts of femora much darker.

Figures 23–28. 

Paracortina yinae sp. n. holotype 23 anterior body, subventral view 24 anterior body, subdorsal view 25 midbody, ventral view 26 midbody, sublateral view 27 posterior body, ventral view 28 posterior body, lateral view.

Figure 29. 

Paracortina yinae sp. n. female paratype.

Collum much narrower than head, with two paramedian spots covered with brown granules, pleurotergite 6 in males strongly enlarged. Prozonae delicately alveolate-areolate; fine longitudinal striations in front of stricture between pro- and metazonae. Two first primary crests on collum relatively large. All crests on the metazonae, ozopores site, pleurotergal setae, and axial line as in P. zhangi sp. n. (Figs 24, 26, 28); setal pattern as in Table 1.

Male leg-pairs 1 and 2 much shorter, leg-pair 3 slightly shorter than following legs (Fig. 23). Midbody legs about 4 (male) or 3 times (female) as long as pleurotergal height, only tibia finely micropapillate ventrally (Fig. 38). Tarsi 1–3 only 1-segmented, from 4 to ultimate pair 2-segmented; tarsal pads present from leg-pairs 3 to about 15. All legs ending with a rather slender, long and curved claw (Figs 1, 2, 15). Coxal sacs present from leg 3 to at least 25, but most abrased. Coxa 2 with a small anterior process and a posterior gonopore, the latter placed on a small cone. Coxa 6 with a small, pointed posterior process (e) (Fig. 30). Coxa 7 with a long, subfalcate and apically pointed posterior (f), and a very strong, rounded anterior process (t) (Fig. 31). Coxae of remaining legs normal. Epiproct simple, with 3+3 anterior and 8+8 posterior tuberculations in transverse rows. Hypoproct, anal valves and spinnerets as in P. zhangi sp. n. (Fig. 27).

Figures 30–33. 

Paracortina yinae sp. n. male paratype 30 leg-pair 6, anterior view 31 leg-pair 7, anterior view 32 gonopods, mesal view 33 gonopods, lateral view.

Gonopods (Figs 32–33, 40–41) yellow-brown to brown basally, seminal groove and telopodite black brown. Coxa with an anterior process (a) and a rather slender process (b), the latter about half the length of telopodite. Prefemur with a large, clavate process (c), densely covered with long macrosetae apically. Femoroidal stem long, slender, rather strongly curved, directed cephalad. Telopodite’s terminal part twisted, trifid, with a digitiform lateral (h), and a slender, apically pointed lobe (t). Solenomere (s) bifid, parasolenomere (ps) much shorter; seminal groove ending on the longer branch.

Female. A little larger than males, pleurotergites 2 and 3 strongly enlarged. Leg-pairs 1 and 3 with tarsal pads (Figs 34–35). Prefemur 3 evidently enlarged (Fig. 35). Leg-pair 2 (Fig. 36) rather strongly reduced down to a pairs of stout, apically deeply biramous remnants in adult females, normal in younger ones. Cyphopods small, densely setae, hidden in membranous sacs, partly extruded, laterally divided in the middle, the smaller part roundly concave apically (Figs 36–37). Coxae 6 and 7 normal, without processes.

Figures 34–37. 

Paracortina yinae sp. n. female paratype 34 leg 1, anterior view 35 leg 3, posterior view 36 leg-pair 2 and cyphopod, anterior view 37 cyphopod, lateral view.

Figures 38–41. 

Paracortina yinae sp. n. male paratype 38 midbody leg, anterior view 39 antenna, lateral view 40 right gonopod, mesal view 41 right gonopod, lateral view.

The species is named in honour of Miss Haomin Yin, an active collector in our team.

The new species differs from its congeners by the presence of small, pointed, posterior processes (e) on coxae 6 and two pairs of processes on coxae 7 in males, as well as in certain specific charaters of the male gonopods and reduced leg-pair 2 in females.

China: Guangxi (Fig. 46).

Cave I (Figs 42–45) is situated at the foot of a karst mountain. It is a large cave, made up of a hall of several layers covered by numerous big rock boulders. We explored approximately 150 meters deep, but then had to withdraw because of a rushing underground river. Other animals also found in this cave are diplopods from the genera Glyphiulus (Spirostreptida, Cambalopsidae) and Eutrichodesmus (Polydesmida, Haplodesmidae), the blind trechine beetle Satotrechus longlinensis Deuve & Tian, 2011, and bats.

Figures 42–45. 

Cave I 42 location 43 entrance 44 cave walls 45 P. yinae sp. n. walking on a rock.

Figure 46. 

Distribution map of Paracortina in China. a P. voluta b P. thallina c P. viriosa d P. serrata e P. carinata f P. leptoclada g P. stimula h P. chinensis i P. zhangi sp. n. j P. yinae sp. n.