Four new species of the Glyphiulus javanicus group from southern China (Diplopoda, Spirostreptida, Cambalopsidae).

Hitherto, 24 species of the Glyphiulus javanicus group have been recorded, all endemic to Southeast Asia, including 14 in China. Nevertheless, this species group needs further exploration. In this context, four new species of this group are described, all collected from limestone caves in Southern China: G. calceussp. n., G. foetidussp. n., G. guangnanensissp. n., and G. impletussp. n. They can be separated easily from each other and other congeners by their carinotaxic formulae, the structures of male legs I, and the gonopods. Due to the absence of any troglomorphic traits in our specimens, they may be troglophilic only.

Introduction

Since Golovatch et al. (2007b) established and revised the -group, one of two groups of the species-rich millipede genus Gervais, 1847, 25 valid species have been recorded up to date. They are endemic to southeast Asia, distributed from PageBreaksouthern China, across Vietnam, Laos, and Thailand, to Java, Indonesia (Golovatch et al. 2007b, Jiang et al. 2017, Likhitrakarn et al. 2017). Among them, fourteen species occur in China, with most of them being cavernicolous:

Golovatch et al., 2011: from a cave in Fushui County, Guangxi Zhuang Autonomous Region;

(Pocock, 1895): from Hong Kong, known only from female material;

Golovatch et al., 2007: from a cave in Chengdu County (possibly Chengdu City), Sichuan Province;

Jiang et al., 2017: from a cave in Muchuan County, Sichuan Province;

Jiang et al., 2017: from two caves in Liangshan Yi Autonomous Prefecture, Sichuan Province;

Golovatch et al., 2007: from three caves in Anshun County, Guizhou Province;

Golovatch et al., 2007: from a cave in Mile County, Yunnan Province;

Golovatch et al., 2007: from a cave in Qianlin County, Guizhou Province;

Golovatch et al., 2007: from two caves in Suiyang County, Guizhou Province;

(Loksa, 1960): from a cave in Fulong Town, Daxin County, Guangxi Zhuang Autonomous Region;

Zhang & Li, 1982: from Qingyuan County, Zhejiang Province;

(Meng & Zhang, 1993): from a cave in Guanling County, Guizhou Province;

Golovatch et al., 2007: from a cave in Shilin County, Yunnan Province;

Mauriès & Nguyen Duy-Jacquemin, 1997: from a cave in Shuicheng County, Guizhou Province.

Recently, several taxonomical surveys of cave millipedes in southern China were carried out. As a result of these investigations, several species of were identified, of which four new species of the -group are described here. Due to the absence of any troglomorphic traits in our specimens, they are thought to be troglophilic. Our findings confirm the hypothesis that southern China harbours an extremely high level of diversity (Golovatch 2015).

Materials and methods

Live specimens were collected by hand from localities in southern China. Type specimens are deposited in the Institute of Biology, Guizhou Academy of Sciences, Guiyang, China ().

Live animals were first observed and photographed with a Canon EOS 5D Mark III camera with a Canon EF 100mm macro lens. All specimens were then preserved in 75 % ethanol. In the lab, some mature specimens were carefully picked out for examinaPageBreaktion, illustration, photography, and measuring using a Leica M205C stereomicroscope equipped with a Leica DFC450 Camera and LAS software (Version 4.1). Scanning electron micrographs (SEM) were taken with a Hitachi S-4800 field emission scanning electron microscope. Their geographical distributions were sketched with ArcGIS software (Ver. 10.2). All images were edited with Adobe Photoshop CC 2015 Software.

Terminology used in this paper follows the descriptions by Golovatch et al. (2007a, b, 2011) and Jiang et al. (2017).

Taxonomy

Order Brandt, 1833

Family Cook, 1895

Genus Gervais, 1847

sp. n.

http://zoobank.org/C306F018-1EAF-40C8-AC73-2208DF00FDA9

Figs 1A , 2 , 3 , 4 , 5 , 6

Figure 1.

Living animals. A sp. n. from Zhoubang Cave B sp. n. from Xianren Cave C sp. n. from Miaopu Cave D sp. n. from Guanyin Cave.

Figure 2.

sp. n., holotype. A anterior part of body, dorsal view B same, lateral view C midbody segments, dorsal view D same, lateral view E posterior part of body, dorsal view F same, ventral view.

Figure 3.

sp. n., holotype. A gnathochilarium, ventral view B legs I, anterior view C legs II, caudal view D legs III, caudal view E cross-section of a midbody segment, caudal view F midbody leg, anterior view. Abbreviations: CP = coxal process; P = penes; T = telopodite.

Figure 4.

sp. n., holotype. A anterior gonopods, caudal view B posterior gonopods, caudal view.

Figure 5.

sp. n., paratype. A anterior gonopods, caudal view B posterior gonopods, caudal view C flagellum of posterior gonopods D microsetae at lateral margin of posterior gonopods. Scale bars: A, B 0.2 mm C, D 0.02 mm.

Figure 6.

sp. n., holotype. A anterior gonopods, caudal view B posterior gonopods, caudal view. Abbreviations: C = coxosternum; CMP = coxosternal mesal process; F = flagellum; L = lamelliform lobe; T = telopodite. Scale bars: A, B 0.2 mm.

Type material.

Holotype male, China: Guangxi Zhuang Autonomous Region, Xilin County, Zhoubang Village, Zhoubang Cave, , alt. 820 m, 9 Jan. 2017, X.K. Jiang, H.M. Chen & X. Guo leg. (IBGAS). Paratypes: 61 males, 87 females and 12 juveniles, same date and locality as holotype (IBGAS).

Other material.

One male, Yunnan Province, Guangnan County, Bamei Town, Ake Village, Miaopu Cave, , alt. 690 m, 8 Jan. 2017, X.K. Jiang, H.M. Chen & X. Guo leg. (IBGAS).

Etymology.

This specific name is derived from the Latin word , meaning ‘smelly’ and refers to the extremely strong and unpleasant smell of the animals.

Diagnosis.

The new species can be diagnosed by the following combination of morphological characteristics: (1) all crests on collum complete and fully developed, carinotaxic formula I–III + P + M; (2) telopodite of male legs I strongly degenerated, bi-segmented, as high as coxal process; (3) coxosternal mesal process of anterior gonopod prolonged and subtriangular; (4) flagellum of posterior gonopod short, with multiple branches at inner margin. See also Key below.

Description.

Body segments with 53–67p + 1–2a + T (holotype 67p + 1a + T). Body size of ca. 45–63 mm long and 2.3–3.0 mm wide (holotype 62 and 2.7 mm, respectively).

Colouration. Brown to dark brown in vivo (Fig. 1A). In fixed condition, head red-brown with yellow dapples; collum yellow-brown, anterior and posterior margins and the crests red-brown; midbody red-brown, lateral crests, ozoporiferous tubercles and anterior rows of metatergal crests light yellow; antennae and legs pale to light yellow (Fig. 2).

Head. Each eye patch with 30–45 pigmented ocelli arranged in five irregular vertical rows (Fig. 2A, B). Antennae slender, 2.88–3.35 mm long. Terminal part of antennomeres V expanded (Fig. 2B). Gnathochilarium with a separate promentum, polytrichous (Fig. 3A).

Collum. All crests on collum complete and fully developed, carinotaxic formula I–III + P + M (Fig. 2A, B).

Body segments. Postcollum constriction modest (Fig. 2A). Metatergal crests well-developed (Fig. 2A–E). Crests divided into two transverse rows of tubercles, carinotaxic formula 2/2+I/i+3/3+I/i+2/2. Anterior tubercle (except ozoporiferous one) small and round, posterior one strip-shaped (Fig. 2A–E). Ozoporiferous tubercles round, wider than high, obviously larger than other tubercles (Fig. 3E). Location of the tubercle behind ozopore relatively medial, set off from ozoporiferous tubercle (Figs 2C–E, 3E). Lateral crests rather small (Fig. 15). Midbody rings round in cross-section (Fig. 3E), 2.02–2.44 mm high (vertical diameter) and 2.15–2.56 mm wide (horizontal diameter), the ratio of height to width 0.92–0.97.

Figure 15.

sp. n., paratype. A anterior gonopods, caudal view B posterior gonopods, caudal view. Scale bars: A, B 0.2 mm.

Telson. Epiproct simple, with a rounded caudal ridge and a strong dorsal tooth (Fig. 2E). Paraprocts convex, polytrichous. Hypoproct crescent-shaped (Fig. 2F).

Walking legs. Slender, 2.71–3.15 mm long, obviously longer than body width (Fig. 3E, F).

Male sexual characters. Male legs I strongly degenerated, with a pair of bi-segmented telopodites and a pair of large, subdigitiform, coxal processes. Coxal processes contiguous medially and curved forward, with clusters of long and robust setae at base (Fig. 3B). Male legs II normal. Penes trapeziform and small, each possessing three robust distolateral setae (Fig. 3C). Male legs III modified, with coxa especially slender and elongated (Fig. 3D). Femora VI and VII normal, not inflated.

Anterior gonopods. Coxosterna shield-like, sunken medially. Coxosternal mesal processes prolonged, obviously higher than telopodites. Telopodites one-segmented, PageBreakplaced laterally, curved and moveable, with several distal setae and a field of microsetae at base (Figs 4A, 5A, 6A).

Posterior gonopods. Compact (Figs 4B, 5B, 6B). Coxite with a medial lamelliform lobe and two rows of strong and curved setae at mediolateral margin. Flagella short with multiple branches at inner margin (Fig. 5C). Lateral margin with a field of microsetae (Fig. 5D).

Distribution.

Known only from the type locality, a cave in Xilin County, Guangxi, and another cave in Guangnan County, Yunnan. The two caves are ca. 35 kilometres apart.

http://zoobank.org/39980A3D-3D10-4EFB-991D-A58E7AC13B54

Figs 1B , 7 , 8 , 9 , 10 , 11

Figure 7.

sp. n., holotype. A anterior part of body, dorsal view B same, lateral view C midbody segments, dorsal view D same, lateral view E posterior part of body, ventral view F same, lateral view.

Figure 8.

sp. n., holotype. A gnathochilarium, ventral view B legs I, anterior view C legs II, caudal view D legs III, caudal view E cross-section of a midbody segment, caudal view F midbody leg, anterior view. Abbreviations: CP = coxal process; P = penes; T = telopodite.

Figure 9.

sp. n., holotype. A anterior gonopods, caudal view B posterior gonopods, caudal view.

Figure 10.

sp. n., paratype. A anterior gonopods, caudal view B posterior gonopods, caudal view C flagellum of posterior gonopods D microsetae at lateral margin of posterior gonopods. Scale bars: A 0.2 mm B 0.15 mm C 0.025 mm D 0.03 mm.

Figure 11.

sp. n., holotype. A anterior gonopods, caudal view B posterior gonopods, caudal view. Abbreviations: C = coxosternum; CMP = coxosternal mesal process; F = flagellum; L = lamelliform lobe; T = telopodite. Scale bars: A, B 0.2 mm.

Holotype male, China: Guangxi Zhuang Autonomous Region, Tian’e County, Bala Town, Madong Village, Hanyaotun, Xianren Cave , alt. 900 m, 2 Jan. 2017, X.K. Jiang, H.M. Chen & X. Guo leg. (IBGAS). Paratypes: Thirteen males, 11 females and 1 juvenile, same date and locality as holotype (IBGAS).

This specific name is derived from the Latin word , meaning ‘shoe’ and refers to the shape of the coxosternal mesal process of the anterior gonopod.

The new species can be diagnosed by the following combination of morphological characteristics: (1) all crests on collum complete and fully developed, carinotaxic formula I–III + P + M; (2) telopodite of male legs I bi-segmented, obviously shorter than coxal process; (3) coxosternal mesal process of anterior gonopod prolonged and shoe-shaped; (4) flagellum of posterior gonopod short and zigzag-shaped. See also Key below.

Body segments with 58–67p + 1–2a + T (holotype with 67p + 1a + T). Body size of ca. 45–63 mm long and 2.6–3.1 mm wide (holotype 58 and 2.9 mm, respectively).

Colouration. Brown to yellow brown in vivo (Fig. 1B); brown to red-brown in fixed condition (Fig. 7A–F).

Head. Each eye patch with 8–15 pigmented ocelli, arranged in two irregular vertical rows (Fig. 7B). Antennae slender, 2.90–3.28 mm long. Terminal part of antennomeres V expanded (Fig. 7B). Gnathochilarium with a separate promentum, polytrichous (Fig. 8A).

Collum. All crests complete and obvious, carinotaxic formula I–III + P + M (Fig. 7A, B).

Body segments. Postcollum constriction obvious (Fig. 7A). Metaterga strongly crested (Fig. 7A–F). Crests with two transverse rows of tubercles, carinotaxic forPageBreakPageBreakPageBreakmula 2/2+I/i+3/3+I/i+2/2. Anterior tubercle (except ozoporiferous one) small and upright, posterior one directed caudally, both with sharp tips (Fig. 7A–F). Ozoporiferous tubercle round, higher than broad, obviously larger than other tubercles (Fig. 8E). Location of the tubercle behind ozopore relatively medial, set off from ozoporiferous tubercle in caudal view (Figs 7C, D, 8E). Lateral crests rather small. Midbody rings round in cross-section (Fig. 8E), 2.10–2.48 mm high (vertical diameter) and 2.19–2.59 mm wide (horizontal diameter), the ratio of height to width 0.95–0.98.

Telson. Epiproct simple, with a rounded caudal ridge and a strong dorsal tooth. Paraprocts convex. Hypoproct crescent-shaped (Fig. 7E, F).

Walking legs. 3.17–3.67 mm long, obviously longer than body width (Fig. 8E, F).

Male sexual characters. Telopodite of male legs I strongly degenerated, bi-segmented. Coxal processes obviously longer than telopodites (Fig. 8B). Penes broad, tongue-shaped (Fig. 8C). Male legs III with slender and elongated coxa (Fig. 8D). Femora VI and VII normal, not inflated.

Anterior gonopods. Coxosternum shield-like, sunken medially. Coxosternal mesal processes of anterior gonopods elongated and shoe-shaped, obviously higher than telopodites. Telopodite one-segmented, curved and moveable, with round tip and a field of microsetae at base (Figs 9A, 10A, 11A).

Posterior gonopods. Mediolateral margins of coxite brush-like. Flagella short and zigzag-shaped (Fig. 10C). A long seta at anterolateral margin (Figs 9B, 11B). Lateral margin with a field of microsetae (Fig. 10D).

Known only from the type locality, a cave in Tian’e County, Guangxi Zhuang Autonomous Region.

http://zoobank.org/EDB6ECE1-6518-443A-8E64-882573FA9B9F

Figs 1C , 12 , 13 , 14 , 15 , 16

Figure 12.

sp. n., holotype. A anterior part of body, dorsal view B same, lateral view C midbody segments, dorsal view D same, lateral view E posterior part of body, ventral view F same, lateral view.

Figure 13.

sp. n., holotype. A gnathochilarium, ventral view B legs I, anterior view C legs II, caudal view D legs III, caudal view E cross-section of a midbody segment, caudal view F midbody leg, anterior view. Abbreviations: CP = coxal process; P = penes; T = telopodite.

Figure 14.

sp. n., holotype. A anterior gonopods, caudal view B posterior gonopods, caudal view.

Figure 16.

sp. n., holotype. A anterior gonopods, caudal view B posterior gonopods, caudal view. Abbreviations: C = coxosternum; CLP = coxosternal lateral process; CMP = coxosternal mesal process; F = flagellum; L = lamelliform lobe; T = telopodite. Scale bars: A, B 0.1 mm.

Holotype male, China: Yunnan Province, Guangnan County, Bamei Town, Ake Village, Miaopu Cave, , alt. 690 m, 8 Jan. 2017, X.K. Jiang, H.M. Chen & X. Guo leg. (IBGAS). Paratypes: 9 males, 12 females and 9 juveniles, same date and locality as holotype (IBGAS).

This specific name is derived from the type locality.

The new species can be diagnosed by the following combination of morphological characteristics: (1) all crests on collum fully developed, carinotaxic formula 1a+2c+III–IV+5c+6a+pc+ma+pc+6a+5c+IV–III+2c+1a; (2) metatergal crests not divided, carinotaxic formula 2+I/i+3+I/i+2 (3) telopodite of male legs I complete, not degenerated, five-segmented; (4) anterior gonopod possessing a coxosternal mesal process and a coxosternal lateral process, coxosternal mesal process with PageBreaka long and sharp tip, coxosternal lateral process with a blunt tip; (5) flagellum of posterior gonopod extremely long and smooth, slightly curved. See also Key below.

Body segments with 56–73p + 1a + T (holotype 73p + 1a + T). Body size of ca. 38–55 mm long and 2.0–2.3 mm wide (holotype 54 and 2.3 mm, respectively).

Colouration. Brown to dark brown in vivo (Fig. 1C); taupe to red-brown in fixed condition (Fig. 12A–F).

Head. Each eye patch with 9–12 pigmented ocelli arranged in 2–3 irregular vertical rows (Fig. 12B). Antennae slender, 2.20–2.38 mm long. Terminal part of antennomeres V slightly expanded (Fig. 12B). Gnathochilarium with a separate promentum, polytrichous (Fig. 13A).

Collum. All crests developed, carinotaxic formula 1a+2c+III–IV+5c+6a+pc+ma+pc+6a+5c+IV–III+2c+1a (Fig. 12A, B).

Body segments. Postcollum constriction modest (Fig. 12A). Metaterga strongly crested (Fig. 12A–F). All metatergal crests undivided (Fig. 12A–D, F), carinotaxic formula 2+I/i+3+I/i+2. Anterior part of crest round and broad, posterior part strip-shaped. Ozoporiferous tubercles large and round, as high as broad. Lateral crests fully developed. Midbody rings round in cross-section (Fig. 13E), 1.70–2.01 mm high (vertical diameter) and 1.74–2.08 mm wide (horizontal diameter), the ratio of height to width 0.96–0.99.

Telson. Epiproct with a rounded caudal ridge and an evident, axial, dorsal rib (Fig. 12F). Paraproct convex, with an evident depression near caudal edge, polytrichous. Hypoproct crescent-shaped (Fig. 12E, F).

Walking legs. 2.64–2.80 mm long, obviously longer than body width (Fig. 13E, F).

Male sexual characters. Telopodite of male legs I complete, five-segmented (Fig. 13B). Penes rather broad and round (Fig. 13C). Male legs II and III modified as usual (Fig. 13C, D). Femora VI and VII normal, not inflated.

Anterior gonopods. Coxosternum shield-like, sunken medially. Distal part of coxosternum with a deep indentation, the latter separating a mesal process and a lateral process. Coxosternal mesal process digitiform, obviously higher than telopodite. Coxosternal lateral process broad, with a blunt tip, nearly as high as telopodite. Telopodite short, one-segmented with thin and round tip and a field of microsetae at base (Figs 14A, 15A, 16A).

Posterior gonopods. Mediolateral margins of coxite brush-like. Flagella smooth, curved and extremely long. Lateral margin with a field of microsetae (Figs 14B, 15B, 16B).

Known only from the type locality, a cave in Guangnan County, Yunnan Province.

Notes.

Since the definitions of and are still uncertain, this new species may be a member of . Mauriès (1977) considered that the two genera are distinguished only by the absence () and presence () of transverse crests on body. Golovatch et al. (2011) dealt with the crests as a species-level character, and transferred Mauriès, 1977 to based on the complete male legs I. However, this arrangement didn’t fully resolve this problem. In the genus , there are still several species which present the same feature of male legs I and were not transferred to , for example , , , , , and . A serious revision of the two genera is definitely needed but until then, this new species is assigned to .

Usually, one cave supports one species of (Likhitrakarn et al. 2017). However, in our investigations, it was found that two species ( sp. n. and sp. n.) could coexist in one place (Miaopu Cave), possibly due to the fact that they are troglophilic. Besides this, sympatry is also true for (likely troglophilic) and (presumably troglobitic) which coexist in another cave (Bailong Cave).

http://zoobank.org/F02E3546-7C94-4C0E-8091-88D4999003B4

Figs 1D , 17 , 18 , 19 , 20 , 21

Figure 17.

sp. n., holotype. A anterior part of body, dorsal view B same, lateral view C midbody segments, dorsal view D same, lateral view E posterior part of body, dorsal view F same, ventral view.

Figure 18.

sp. n., holotype. A gnathochilarium, ventral view B legs I, anterior view C legs II, caudal view D legs III, caudal view E cross-section of a midbody segment, caudal view F midbody leg, anterior view. Abbreviations: CP = coxal process; P = penes; T = telopodite.

Figure 19.

sp. n., holotype. A anterior gonopods, caudal view B posterior gonopods, caudal view.

Figure 20.

sp. n., paratype. A anterior gonopods, caudal view B posterior gonopods, caudal view C flagellum of posterior gonopods D microsetae at lateral margin of posterior gonopods. Scale bars: A 0.2 mm B 0.15 mm C, D 0.3 mm.

Figure 21.

sp. n., holotype. A anterior gonopods, caudal view B posterior gonopods, caudal view. Abbreviations: C = coxosternum; CMP = coxosternal mesal process; F = flagellum; L = lamelliform lobe; T = telopodite. Scale bars: A, B 0.1 mm.

Holotype male, China: Guangxi Zhuang Autonomous Region, Lingyun County, Luolou Town, Geding Village, Longcitun, Guanyin Cave , alt. 830 m, 4 Jan. 2017, X.K. Jiang, H.M. Chen & X. Guo leg. (IBGAS). Paratypes: 22 males, 26 females and 9 juveniles, same date and locality as holotype (IBGAS); 17 males, 14 females and 43 juveniles, Lingyun County, Luolou Town, Geding Village, Longweitun, Paifang Cave , alt. 830 m, 4 Jan. 2017, X.K. Jiang, H.M. Chen & X. Guo leg. (IBGAS).

Other material examined.

Seven males, 6 females and 4 juveniles, Lingyun County, Sicheng Town, Shuiyuan Cave , alt. 450 m, 3 Jan. 2011, H.M. Chen leg. (IBGAS); 17 males and 14 females, Lingyun County, Sicheng Town, Naling Cave , alt. 500 m, 4 Jan. 2011, H.M. Chen leg. (IBGAS); 3 males and 1 female, Fengshan County, Yuanyang Cave , alt. 640 m, 3 Jan. 2017, X.K. Jiang, H.M. Chen & X. Guo leg. (IBGAS); 1 male, 2 females and 1 juvenile, Nandan County, Bachuan Cave , 31 PageBreakJan. 2017, H.M. Chen & C. Chen leg. (IBGAS); 17 males, 24 females and 24 juveniles, Donglan County, Xinyan Village, Qiumotun, Ganma Cave , alt. 320 m, 2 Feb. 2017, H.M. Chen & C. Chen leg. (IBGAS).

This specific name is derived from the Latin word , meaning ‘plentiful’, referring to the large number of specimens of the new species in our collections.

The new species can be diagnosed by the following combination of morphological characteristics: (1) all crests on collum complete and fully developed, carinotaxic formula I–III + P + M; (2) telopodite of male leg I bi-segmented, shorter than coxal process; (3) coxosternal mesal process of anterior gonopod slender and strongly prolonged; (4) flagellum of posterior gonopod short and zigzag-shaped. See also Key below.

Body segments with 71–82p + 1a + T (holotype 73p + 1a + T). Body ca. 51–66 mm long and 2.3–3.2 mm wide (holotype 64 mm and 3.0 mm, respectively).

Colouration. Brown to dark brown in vivo (Fig. 1D). In fixed condition, yellow-brown to red-brown, tergal crests dark red-brown to castaneous brown (Fig. 17A–F).

Head. Each eye patch with 7–20 pigmented ocelli arranged in 1–3 irregular vertical rows (Fig. 17A, B). Antennae slender, 2.34–3.31 mm long. Terminal part of antennomeres V obviously expanded (Fig. 17B). Gnathochilarium with a separate promentum, polytrichous (Fig. 18A).

Collum. All crests on collum complete and fully developed, carinotaxic formula I–III + P + M (Fig. 17A, B).

Body segments. Postcollum constriction modest (Fig. 17A). Metaterga strongly crested (Fig. 17A–E). Metatergal crests divided into two transverse rows of tubercles, carinotaxic formula 2/2+I/i+3/3+I/i+2/2. Anterior tubercle (except ozoporiferous one) small and upright, posterior one directed caudally, both tubercles with sharp tips (Fig. 17A–E). Ozoporiferous tubercle round, higher than broad, obviously larger than PageBreakother tubercles (Fig. 18E). Location of the tubercle behind ozopore relatively medial, set off from ozoporiferous tubercle in caudal view (Figs 17B–E, 18E). Lateral crests well developed. Midbody rings round in cross-section (Fig. 18E), 1.88–2.42 mm high (vertical diameter) and 1.91–2.42 mm wide (horizontal diameter), the ratio of height to width 0.95–1.00.

Telson. Epiproct simple, with a rounded caudal ridge and a strong dorsal tooth. Paraprocts convex, polytrichous. Hypoproct crescent-shaped (Fig. 17E, F).

Walking legs. Slender, 2.52–3.41 mm long, longer than body width (Fig. 18E, F).

Male sexual characters. Telopodite of male legs I strongly degraded, bi-segmented (Fig. 18B). Penes rather small and oval (Fig. 18C). Male legs II and III modified as usual (Fig. 18C, D). Femora VI and VII normal, not inflated.

Anterior gonopods. Coxosternum shield-like, sunken medially. Coxosternal mesal process slender and strongly prolonged. Telopodite thin, curved with a rounded tip, and a field of microsetae at base (Figs 19A, 20A, 21A).

Posterior gonopods. Mediolateral margins of coxite brush-like. Flagella short and zigzag-shaped. Lateral margin with a field of microsetae (Figs 19B, 20B, 21B).

Known from the type locality and several caves scattered in northwestern Guangxi.

Distributions of sp. n., sp. n., sp. n. and sp. n.

1	Crests on collum fully developed (Figs 2A, 7A, 12A, 17A)	2
–	At least some crests on collum more or less obliterated	12
2	All crests on collum complete, carinotaxic formula of collum I–III + P + M (Figs 2A, 7A, 17A); epiproct with a strong dorsal tooth (Figs 2E, 7F, 17E); paraprocts convex (Figs 2F, 7E, 17F); telopodites of male legs I strongly reduced, 1–3-segmented (Figs 3B, 8B, 18B); flagella of posterior gonopods short (Figs 4B, 9B, 19B)	3
–	Not all crests on collum complete (Fig. 12A); epiproct with an axial dorsal rib (Fig. 12F); paraproct convex, with an evident depression near caudal edge (Fig. 12E); telopodites of male legs I normal or slightly reduced in size, 4–5-segmented (Fig. 13B); flagella of posterior gonopods long (Fig. 14B)	8
3	Coxosternal mesal processes of anterior gonopods elongated, obviously higher than telopodites (Figs 4A, 9A, 19A)	4
–	Coxosternal mesal processes of anterior gonopods short	6
4	Flagella of posterior gonopods with multiple branches (Fig. 5C)	G. foetidus sp. n.
–	Flagella of posterior gonopods zigzag-shaped (Figs 10C, 20C)	5
5	Coxosternal mesal processes of anterior gonopods shoe-shaped (Figs 9A, 10A, 11A)	G. calceus sp. n.
–	Coxosternal mesal processes of anterior gonopods thin and strongly elongated (Figs 19A, 20A, 21A)	G. impletus sp. n.
6	Male femora VI and VII inflated	G. recticullus
–	Male femora VI and VII normal, not inflated	7
7	Telopodites of male legs I one-segmented; anterior gonopod coxosternum lower than telopodites	G. pulcher
–	Telopodites of male legs I bi-segmented; anterior gonopod coxosternum higher than telopodites	G. echinoides
8	Carinotaxic formula of collum 1a+2c+III–IV+5c+6a+pc+ma (Fig. 12A, B)	G. guangnanensis sp. n.
–	Carinotaxic formula of collum not as above	9
9	Carinotaxic formula of collum I–III+4c+5a+pc+ma	10
–	Carinotaxic formula of collum I+2c+III–IV+5c+6a+pc+ma	11
10	Carinotaxic formula of midbody segments 2/2+I/i+3/3+I/i+2/2; coxosternal mesal processes of anterior gonopods broad	G. latus
–	Carinotaxic formula of midbody segments 2+I/i+3+I/i+2; coxosternal mesal processes of anterior gonopods slender	G. paracostulifer
11	Telopodites of male legs I normal, five-segmented; coxosternal mesal processes of anterior gonopods elongated and strong; lamelliform lobes of posterior gonopods obviously elongated	G. intermedius
–	Telopodites of male legs I reduced in size, five-segmented; coxosternal mesal processes of anterior gonopods slender; lamelliform lobes of posterior gonopods short	G. liangshanensis
12	Telopodites of male legs I normal; coxosternal mesal processes of anterior gonopods elongated; flagella of posterior gonopods long	G. parobliteratus
–	Telopodites of male legs I reduced in size, 4–5-segmented; coxosternal mesal processes of anterior gonopods not elongated; flagella of posterior gonopods absent	13
13	Collum not completely smooth, only medial crests obliterated	G. zorzini
–	Collum smooth, without apparent longitudinal crests	14
14	Coxosternal mesal processes of anterior gonopods folded	G. obliteratoides
–	Coxosternal mesal processes of anterior gonopods not folded	15
15	Carinotaxic formula of midbody segments 1/1+I/i+3+I/i+1/1; telopodites of male legs I with a claw	G. obliteratus
–	Carinotaxic formula of midbody segments 2/2+I/i+3/3+I/i+2/2; telopodites of male legs I without claw	16
16	Lamelliform lobes of posterior gonopods elongated	G. sinensis
–	Lamelliform lobes of posterior gonopods short	G. subobliteratus