Research Article |
Corresponding author: J. Judson Wynne ( jut.wynne@nau.edu ) Academic editor: Oana Teodora Moldovan
© 2019 Weixin Liu, J. Judson Wynne.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Liu WX, Wynne JJ (2019) Cave millipede diversity with the description of six new species from Guangxi, China. Subterranean Biology 30: 57-94. https://doi.org/10.3897/subtbiol.30.35559
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We synthesized the current knowledge of cave-dwelling millipede diversity from Guangxi Zhuang Autonomous Region (Guangxi), South China Karst, China and described six new millipede species from four caves from the Guilin area, northeastern Guangxi. Fifty-two cave-dwelling millipedes are known for the region consisting of 38 troglobionts and 14 troglophiles. Of the troglobionts, 24 are presently considered single-cave endemics. New species described here include Hyleoglomeris rukouqu sp. nov. and Hyleoglomeris xuxiakei sp. nov. (Family Glomeridae), Hylomus yuani sp. nov. (Family Paradoxosomatidae), Eutrichodesmus jianjia sp. nov. (Family Haplodesmidae), Trichopeltis liangfengdong sp. nov. (Family Cryptodesmidae), and Glyphiulus maocun sp. nov. (Family Cambalopsidae). Our work also resulted in range expansions of Pacidesmus trifidus Golovatch & Geoffroy, 2014, Blingulus sinicus Zhang & Li, 1981 and Glyphiulus melanoporus Mauriès & Nguyen Duy-Jacquemin, 1997. As with many hypogean animals in Southeast Asia, intensive human activities threaten the persistence of both cave habitats and species. We provide both assessments on the newly described species’ distributions and recommendations for future research and conservation efforts.
Single cave endemic, disturbance relict, cave conservation
Southeast Asia is considered the most biologically diverse for troglomorphic animals among the well-sampled tropical regions of the globe (
Common in cave-arthropod communities, millipedes represent a dominant and widespread group in southern China (
Fifty-two known cave-dwelling millipede species from Guangxi, South China Karst, China. ‘Order: Family: Species’, ‘Functional Group’ (TB=presumed troglobiont, TP=troglophile), number of caves (# Caves) to suggest a level of potential endemism), and main Reference(s) are provided. As troglophiles are expected to have regional distributions, the number of caves where TPs were detected is not included.
Order: Family: Species | Functional group | # Caves | Reference(s) |
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Glomerida: Glomeridae | |||
Hyleoglomeris baxian Liu & Tian, 2015 | TB | 1 |
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Hyleoglomeris curtisulcata Golovatch, Liu & Geoffroy, 2012 | TB | 1 |
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Hyleoglomeris grandis Liu & Tian, 2015 | TB | 1 |
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Hyleoglomeris heshang Golovatch, Liu & Geoffroy, 2012 | TB | 1 |
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Hyleoglomeris kunnan Golovatch, Liu & Geoffroy, 2012 | TB | 1 |
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Hyleoglomeris lii Golovatch, Liu & Geoffroy, 2012 | TP | – |
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Hyleoglomeris mashanorum Golovatch, Liu & Geoffroy, 2012 | TB | 1 |
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Hyleoglomeris mulunensis Golovatch, Liu & Geoffroy, 2012 | TB | 1 |
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Hyleoglomeris rukouqu sp. nov. | TP | – | This study |
Hyleoglomeris xueju Golovatch, Liu & Geoffroy, 2012 | TB | 1 |
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Hyleoglomeris xuxiakei sp. nov. | TB | 1 | This study |
Polydesmida: Cryptodesmidae | |||
Trichopeltis liangfengdong sp. nov. | TB | 1 | This study |
Haplodesmidae | |||
Eutrichodesmus distinctus Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2009 | TB | 1 |
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Eutrichodesmus jianjia sp. nov. | TB | 1 | This study |
Eutrichodesmus latus Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2009 | TB | 4 |
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Eutrichodesmus lipsae Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2015 | TB | 1 |
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Eutrichodesmus planatus Liu & Tian, 2013 | TB | 1 |
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Eutrichodesmus similis Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2009 | TB | 2 |
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Paradoxosomatidae | |||
Piccola golovatchi Liu & Tian, 2015 | TB | 1 |
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Hylomus longispinus (Loksa, 1960) | TB | 1 |
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Hylomus lui (Golovatch, Li, Liu & Geoffroy, 2012) | TB | 1 |
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Hylomus nodulosus (Liu, Golovatch & Tian, 2014) | TP | – |
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Hylomus phasmoides (Liu, Golovatch & Tian, 2016) | TB | 1 |
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Hylomus scolopendroides Golovatch, Geoffroy & Mauriès, 2010 | TB | 4 |
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Hylomus scutigeroides Golovatch, Geoffroy & Mauriès, 2010 | TB | 6 |
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Hylomus spinissimus (Golovatch, Li, Liu & Geoffroy, 2012) | TB | 1 |
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Hylomus variabilis (Liu, Golovatch & Tian, 2016) | TP | – |
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Hylomus yuani sp. nov. | TB | 1 | This study |
Polydesmidae | |||
Epanerchodus orientalis Attems, 1901 | TP | – |
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Pacidesmus armatus Golovatch, Geoffroy & Mauriès, 2010 | TB | 3 |
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Pacidesmus bedosae Golovatch, Geoffroy & Mauriès, 2010 | TB | 3 |
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Pacidesmus bifidus Golovatch & Geoffroy, 2014 | TB | 1 |
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Pacidesmus tiani Golovatch, Geoffroy & Mauriès, 2010 | TB | 2 |
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Pacidesmus trifidus Golovatch & Geoffroy, 2014 | TB | 4 |
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Callipodida: Paracortinidae | |||
Paracortina yinae Liu & Tian, 2015 | TP | – |
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Spirostreptida: Pericambalidae | |||
Bilingulus sinicus Zhang & Li, 1981 | TP | – |
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Parabilingulus aramulus Zhang & Li, 1981 | TP | – |
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Parabilingulus simplicius Mauriès & Nguyen Duy-Jacquemin, 1997 | TP | – |
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Cambalopsidae | |||
Hypocambala polytricha Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2011 | TB | 1 |
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Glyphiulus acutus Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2011 | TB? | 2 |
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Glyphiulus calceus Jiang, Guo, Chen & Xie, 2018 | TP | – |
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Glyphiulus difficilis Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2011 | TB | 2 |
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Glyphiulus echinoides Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2011 | TP | – |
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Glyphiulus foetidus Jiang, Guo, Chen & Xie, 2018 | TP | – |
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Glyphiulus impletus Jiang, Guo, Chen & Xie, 2018 | TP | – |
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Glyphiulus maocun sp. nov. | TB | 1 | This study |
Glyphiulus melanoporus Mauriès & Nguyen Duy-Jacquemin, 1997 | TP | – |
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Glyphiulus mulunensis Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2011 | TB | 2 |
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Glyphiulus paramulunensis Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2011 | TB | 2 |
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Glyphiulus proximus Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2011 | TB | 2 |
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Glyphiulus speobius Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2011 | TB | 2 |
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Glyphiulus tiani Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2011 | TB | 1 |
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In the paper, we describe six new species (representing five families, Glomeridae, Paradoxosomatidae, Haplodesmidae, Cryptodesmidae and Cambalopsidae), as well as discuss range expansions of three additional cave-dwelling species. We have also summarized the cave-dwelling millipedes known to Guangxi, their known distributions, and provide recommendations to guide future research and management efforts.
Located in southwest China, Guangxi encompasses 236,700 km2. Once an ancient shallow sea during the middle Cambrian to Late Triassic periods, this region is now largely characterized by a massive karst (limestone) stratum over 10,000 m thick (
We sampled four caves in the northeastern most extent of Guangxi within a 30 km radius of the city of Guilin, China (Fig.
All caves occurred at low elevations within tower karst formations. While extensive agriculture, as well as rural village and suburban habitation characterized the surrounding lowlands, vegetation on the tower karst represented a marginally disturbed combination of native and introduced plant and tree species.
Based on our knowledge of the South China Karst (SCK) cave-dwelling millipede literature, we summarized the total number of caves sampled and cave-dwelling millipedes detected for Guangxi. For selected species occurring within two or more caves, we determined maximum distances between caves and, in some cases, average distances across all caves using ArcGIS 10.6.1.
We hand collected cave-dwelling arthropods at four caves from 15 to 18 November 2016. Approximately eight hours (2 observers at 4 hours per observer) was spent conducting direct intuitive searches within estimated deep zones of each cave. We examined bat guano, dead insects, mud banks and floors, flood detritus, or vegetation brought in by humans and deposited within the cave. Given the four caves varied in size and the diversity of arthropods encountered, the areal extent sampled varied. We also sampled the vegetation within the entrance of Liangfeng Cave applying a direct intuitive search approach. For all four caves, we also opportunistically collected arthropods as encountered while transiting from entrance to estimated deep zones. Sampling methods were applied sensu stricto
All specimens examined in this study were collected by the second author in the Guilin area, Guangxi, southern China and preserved in 95% ethanol. Holotypes and paratypes are deposited in the Zoological Collection of the South China Agricultural University, Guangzhou, Guangdong Province, China (SCAU). Detailed examination of characters and dissections were performed using a Leica S8 APO stereo microscope. Line drawings were prepared with a ZEISS Axioskop40 microscope with a camera lucida attached. Photographs were taken using a Keyence VHX-5000 digital microscope, and further edited using Adobe Photoshop CS5.
We recognize standard practice for new species description is to provide sample locality information including geographical data to facilitate future collecting, interpretation and research. Because caves often represent sensitive resources, we provided general geographical information and offset the latitude and longitude coordinates by ~1 km. This level of detail is sufficient for future comparative studies, while protecting the precise location of our study caves.
Cave ecosystems typically consist of four zonal environments (
Since ~1960, at least 49 caves have been sampled for cave-dwelling millipedes. Of these, nearly half (24 caves) supported single-cave endemic troglobionts, nine caves supported at least two troglobitic millipede species, and three caves (present study; Table
Nine cave-dwelling millipedes including both troglobitic and potentially relict species from four caves near Guilin, Guangxi, South China Karst, China.
Species | Maomaotou cave | Guanshan No. 4 cave | Shangshuiyan cave | Liangfeng cave |
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Hyleoglomeris rukouqu sp. nov. | – | – | × | – |
Hyleoglomeris xuxiakei sp. nov. | – | × | – | – |
Hylomus yuani sp. nov. | – | – | – | × |
Eutrichodesmus jianjia sp. nov. | – | × | – | – |
Trichopeltis liangfengdong sp. nov. | – | – | – | × |
Pacidesmus trifidus | × | × | × | – |
Blingulus sinicus | × | – | × | × |
Glyphiulus melanoporus | × | – | – | – |
Glyphiulus maocun sp. nov. | – | – | – | × |
Fourteen troglomorphic millipede species detected in more than one cave, Guangxi, South China Karst, China. ‘Order: Family: Species’, number of caves (# Caves) to suggest a level of potential endemism), and maximum distance between caves in kilometers (Max Dist.) are provided. *Indicates coordinate data for all caves was unavailable for that species. ‘?’ denotes maximum distance was indeterminable due to lack of cave coordinate data. ‘Landscape features’ potentially affecting distribution of caves separated by more than 10 km.
Order: Family: Species | # Caves | Max dist. (km) | Landscape features |
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Polydesmida: Haplodesmidae | |||
*Eutrichodesmus latus | 4 | 14.32 | Maximum distance between two caves provided, the third cave occurs in between the two. |
*Eutrichodesmus similis | 2 | ? | |
Paradoxosomatida | |||
Hylomus scolopendroides | 4 | 81.27 | Three caves clustered within 21.24 km; one cave separated by Diaojiang, Hongshui and Jincheng Rivers and lowland areas |
Hylomus scutigeroides | 6 | 137.6 | One cave separated from others by Hongshui River; others may occur in same formation |
Polydesmidae | |||
*Pacidesmus armatus | 3 | 12.4 | Two of three caves separated by lowland areas |
*Pacidesmus bedosae | 3 | 2.67 | |
Pacidesmus tiani | 2 | 1.88 | |
Pacidesmus trifidus | 4 | 59.7 | Separated by lowland areas |
Spirostreptida: Cambalopsidae | |||
Glyphiulus acutus | 2 | 8.85 | |
Glyphiulus difficilis | 2 | 9.32 | |
Glyphiulus mulunensis | 2 | 7.77 | |
Glyphiulus paramulunensis | 2 | 6.67 | |
Glyphiulus proximus | 2 | 2.67 | |
Glyphiulus speobius | 2 | 11.22 | Separated by lowland areas |
A total of nine cave-dwelling millipede species were collected from four caves near Guilin (Table
Type species. Hyleoglomeris multilineata Verhoeff, 1910.
Remarks. The genus can be characterized by the telopods, which with frontomesal trichosteles on the prefemur and femur, and the caudomesal femoral process forming a distinct angle to femur proper (
Holotype male (SCAU), China, Guangxi Zhuang Autonomous Region, Yangshou County, Shangshuiyan Cave [24°57'43.6"N, 110°20'37.21"E], 191 m elevation (el.), cave entrance, ferns and other vegetation (refer to habitat section below), direct intuitive search, 17 November 2016, J.J. Wynne leg. Paratype, 1 female (SCAU), same data as holotype.
The species name, rukouqu, is used as a noun in apposition from the Mandarin phrase, rùkǒu qū (入口区). When translated to English it means “entrance zone” or “entrance area” to denote the area in the cave where this species was collected.
Adult male of H. rukouqu sp. nov. is distinct from other Hyleoglomeris species based on the following combination of characters: (1) peculiar color pattern (Fig.
Based on type specimens. Length ca 8.0 mm (holotype), 11.0 mm (paratype), width 5.0 mm (holotype), 7.0 mm (paratype). Coloration: pattern vivid (Fig.
Specimens were collected within a vegetation association that may be limited to the cave entrance zone and similar geographic features (e.g., sinkholes and fissures in rock). At least three plant species occurred within the entrance including Gesneriaceae sp., Adiantum sp., and one other fern species, which cannot be identified without examining the sorii (A. Monro, pers. comm. 2018).
Based on the vivid color pattern and well-developed ommatidia, as well as the location where it was detected within the cave, this animal represents an epigean species and may be functioning as an obligate troglophile (sensu
Holotype male (SCAU), China, Guangxi Zhuang Autonomous Region, Yangshuo County, Guanshan No. 4 Cave [24°56'58.34"N, 110°20'53.52"E], 186 m el., deep zone, direct intuitive search, 16 November 2016, J.J. Wynne leg. Paratype, 1 male (SCAU), same data as holotype. 3 females (SCAU), same data as holotype, but deep zone, slightly muddy flat area.
The species name, xuxiakei, was Latinized using a combination of the surname and forename of Xu Xiake (徐霞客). Xu was a traveler, explorer, and the first speleologist of China, who studied caves and karst geology during the decline of the Ming Dynasty. He conducted a four-year expedition (1636–1640) across southern China where he examined over 300 caves (including more than 100 from the Guilin area;
Adult male of H. xuxiakei sp. nov. is distinct from other Hyleoglomeris species based on the following combination of characters: (1) nearly pallid color (Fig.
Based on type specimens. Lengths of body ca 3.8–4.5 mm, width 2.5 –3.0 mm in both sexes. Coloration: entirely pallid (Figs
This species was collected from a chamber within the estimated cave deep zone, approximately 50 m from the cave entrance. Cave sediment was compact mud with a small amount of rock breakdown from the ceiling.
Based on a depigmented habitus and translucent ommatidia, we consider this species is a troglobiont.
Type species. Hylomus draco Cook & Loomis, 1924.
Remarks. The genus is often referred to as “dragon millipedes” because of the paraterga is antler-like, wing-shaped or spiniform. It can be characterized by the collum and metaterga often with granulate, tuberculate and/or speculate; male femora (5, 6, 7 and/or 9) often humped ventrally; and gonopods mostly suberect, some subfalcated, a shortened solenomere mostly sheathed by a usually condensed, rather simple solenophore (
Holotype male (SCAU), China, Guangxi Zhuang Autonomous Region, Lingchuan County, Liangfeng Cave [25°12'34.86"N, 110°31'56.8"E], 184 m el., deep zone, direct intuitive search, 18 November 2016, J.J. Wynne leg. Paratypes, 1 male, 3 females (SCAU), same data as holotype.
This species is named for Dr. Yuan Daoxian (袁道先), a preeminent and globally recognized Chinese hydrologist. He has made numerous significant contributions in advancing both the science and management of karst and karst waters in southern China since the 1960s.
Adult males of H. yuani sp. nov. are distinct from other Hylomus species based on the following combination of characters: (1) paraterga long and spiniform only on collum and rings 2–6, short and coniform thereafter (Figs
Based on type specimens. Lengths of body ca 27–28 (♂), 30–35 mm (♀); width of mid-body pro- and metazonae 1.5–1.6 and 2.0 (♂), 2.0–2.2 and 2.5–2.6 mm (♀). Coloration: light brownish to nearly pallid (Figs
This species was collected within the estimated cave deep zone, approximately 20 m from the cave entrance. Cave sediment was compact mud and the passageway was swaddled by a slightly visible fog. This species and cave crickets (family Rhaphidophoridae) were among the most abundant species within this portion of cave deep zone.
Based on the slender elongate antennae and legs, a depigmented cuticle, the species is considered a troglobiont.
Type species. Eutrichodesmus demangei Silvestri, 1910.
Remarks. The genus can be characterized by the body often capable of volvation, with or without mid-dorsal projections; paraterga 2 strongly enlarged; and gonopod femorite with a more or less distinct process or outgrowth laterally (
Holotype male (SCAU), China, Guangxi Zhuang Autonomous Region, Yangshuo County, Guanshan No. 4 Cave [24°56'58.34"N, 110°20'53.52"E], 186 m el., deep zone, direct intuitive search, 16 November 2016, J. J. Wynne leg. Paratypes, 4 females, 1 juv. (SCAU), same data as holotype; 1 male (SCAU), same data as holotype, but collected on mud bank.
The species name, jianjia (肩甲), is used as a noun in apposition. This phrase was used to denote the well-developed paraterga, which covers the millipede’s legs much like the pauldrons of body armor cover the shoulder of the warrior.
Adult males of E. jianjia sp. nov. is distinct from other Eutrichodesmus species based on the following combination of characters: (1) collum with five, and metaterga 2–19 with three transverse rows of round microvillose tubercles (Fig.
Based on type specimens. Lengths of adult body ca 6.0–7.0 mm, widths of mid-body pro- and metazonae 0.6–1.0 and 1.2–1.3 mm in both sexes. Coloration: generally light-yellowish to pallid (Fig.
Specimens were collected in the same general location as H. xuxiakei sp. nov. specimens. Thus, refer to the H. xuxiakei sp. nov. habitat description.
Based on the long slender legs and a depigmented cuticle, we consider this species a troglobiont.
Type species. Cryptodesmus bicolor Pocock, 1894.
Remarks. The genus can be characterized by the metaterga distinctly several transverse rows of tuberculations, usually setose, and gonopod usually foliate, with a tripartite or deeply notched telopodite. It encompasses 12 species distributed from the Himalayas of India, through Bangladesh, Myanmar to southern China, Laos, Vietnam, Cambodia and Indonesia (
Holotype male (SCAU), China, Guangxi Zhuang Autonomous Region, Lingchuan County, Liangfeng Cave [25°12'34.86"N, 110°31'56.8"E], 184 m el., deep zone, steam bank, direct intuitive search, 18 November 2016, J.J. Wynne leg. Paratypes, 4 females (SCAU), same data as holotype.
This species name, liangfengdong, is used as a noun in apposition and is the name of the type locality.
Adult male of T. liangfengdong sp. nov. is distinct from other Trichopeltis species based on the following combination of characters: (1) metaterga 2–15 with four transverse rows of small, setigerous tubercles (Fig.
Based on type specimens. Length of both sexes ca 14.0–15.0 mm, widths of mid-body pro- and metazonae 1.5–2.0 and 4.8–5.0 mm. Coloration: generally pallid (Fig.
Specimens were collected in the same general location as H. yuani sp. nov. specimens. Thus, refer to the H. yuani sp. nov. habitat description.
Based on the long slender antennae and legs and a depigmented cuticle, the species is considered a troglobiont.
Type species. Pacidesmus shelleyi Golovatch, 1991
Remarks. The genus can be characterized by metaterga often with three transverse rows of 3+3 sculpture, and gonopod structure showing no prominent clivus to recurve laterad of the seminal groove (
6 males, 3 females (SCAU), China, Guangxi Zhuang Autonomous Region, Yangshuo County, Guanshan No. 4 Cave [24°56'58.34"N, 110°20'53.52"E], 186 m el., deep zone, direct intuitive search, 16 November 2016, J.J. Wynne leg. 1 male, 1 juv. (SCAU), China, Guangxi Zhuang Autonomous Region, Xiufeng District, Maomaotou Cave [25°18'46.12"N, 110°16'12.64"E], 225 m el., deep zone, direct intuitive search, 15 November 2016, J. J. Wynne leg. 2 males, 1 female, 4 juv. (SCAU), China, Guangxi Zhuang Autonomous Region, Yangshou County, Shangshuiyan Cave [24°57'43.6"N, 110°20'37.21"E], 191 m el., deep zone, direct intuitive search, 17 November 2016, J. J. Wynne leg.
This troglobiont was first found in Skeleton Cave [25°17'13"N, 110°13'26"E], el. 186 m (
This species was collected from the estimated deep zones of the three caves. For Maomaotou cave, we collected it within bamboo detritus at mid-cave. In Shangshuiyan Cave, specimens were collected within decomposing detritus and along muddy cave sediment deposits within a sinuous passageway. For Guangshan No. 4 Cave, refer to habitat descriptions of H. xuxiakei sp. nov.
Type species. Bilingulus sinicus Zhang & Li, 1981.
Remarks. The genus can be characterized by the lingular lamellae divided into two parts. ♂ legs 1 with a syncoxite carry a pair of long, band-like coxal process; femur with a finger-shaped process at the end protruding posteriorly, tarsus without claw at the end. Anterior gonopod with a very broad coxa; telopodite of posterior gonopod slender, devoid of branch (
3 males, 3 females, 5 juv. (SCAU), China, Guangxi Zhuang Autonomous Region, Yangshou County, Shangshuiyan Cave [24°57'43.6"N, 110°20'37.21"E], 191 m el., deep zone, cartography station #19, direct intuitive search, 17 November 2016, J.J. Wynne leg. 4 females (SCAU), China, Guangxi Zhuang Autonomous Region, Xiufeng District, Maomaotou Cave [25°18'46.12"N, 110°16'12.64"E], 225 m el., deep zone, direct intuitive search, 15 November 2016, J.J. Wynne leg. 1 juv. (SCAU), China, Guangxi Zhuang Autonomous Region, Lingchuan County, Liangfeng Cave [25°12'34.86"N, 110°31'56.8"E], 184 m el., deep zone, direct intuitive search, 18 November 16, J.J. Wynne leg.
This species lacked characters suggestive of troglomorphy. It had a pigmented cuticle and ommatidia were present. Thus, B. sinicus is considered a troglophile. It was first described by
Type species. lulus (recte: Julus) granulatus Gervais, 1847.
Remarks. The genus has been divided into two groups, granulatus-group and javanicus-group. Both groups shared the same gonopods characters as the anterior gonopods usually with a plate-like coxosternum, 1-segmented telopodite. Posterior gonopods highly compressed, showing a plumose, subflagelliform, distal process (
1 male, 1 female, 1 juv. (SCAU), China, Guangxi Zhuang Autonomous Region, Xiufeng District, Maomaotou Cave, [25°18'46.12"N, 110°16'12.64"E], 225 m el., deep zone, direct intuitive search, 15 November 2016, J. J. Wynne leg.
G. melanoporus is considered a troglophile. The type locality for this species is Skeleton Cave [25°17'13"N, 110°13'26"E] (
For our specimens, we collected them within the deep zone of Maomaotou Cave. Sediment where specimens were collected was compacted and wet.
Holotype male, China, Guangxi Zhuang Autonomous Region, Lingchuan County, Maocun Village, Liangfeng Cave [25°12'34.86"N, 110°31'56.8"E], 184 m el., deep zone, direct intuitive search, 18 November 2016, J.J. Wynne. Paratypes, 4 females, 4 juv. (SCAU), same data as holotype.
The species name, maocun, is used as a noun in apposition and is the name of the village nearest to the type locality.
This new species is similar to G. melanoporus (from caves in Guilin) in showing carinotaxy formula of collum I–IV+5c+6a+pc+ma. However, G. maocun sp. nov. is distinct from G. melanoporus by (1) carinotaxy formula of metaterga 2/2+I/i+3/3; (2) anterior gonopod with a conspicuous, high, curved downward process on coxosternum (Figs
Based on the type specimens. Lengths of both sexes ca 26–32 mm, mid-body rings round in cross-section, their widths and heights similar, 1.2–1.8 mm. Coloration: yellow-brown to brownish in alcohol. Ommatidia blackish (Fig.
Specimens were collected within or at proximity to flood detritus.
Specimens exhibited no characteristics suggestive of cave adaptation. It had a pigmented cuticle and well-developed blackish ommatidia. We consider this species to be troglophillic within Liangfeng Cave. Subsequently, this species may have a larger, more regional distribution.
Our work increased the number of subterranean-adapted millipedes from 34 to 38 species. With 564 known caves in Guangxi (Yuanhai Zhang, pers. comm. 2019), but a fraction (8.7% or 49 caves) of these caves have been examined for troglomorphic millipedes. The identification of six new species of millipedes from four caves in the Guilin area underscores the potential for many additional discoveries. For millipede-specific surveys, direct intuitive searches of selected cave deep zones (sensu
Conversely, while advancing our knowledge of regional troglomorphic millipede diversity stands to contribute significantly to the conservation value of the SCK, a more comprehensive understanding (i.e., for all cave-dwelling taxa) of regional diversity, as well as advancing procedures to assessing the vulnerability of cave systems to anthropogenic impact should be considered.
Moreover, for conservation biologists and resource managers to best evaluate the importance of SCK cave biological diversity, we will require a more robust understanding of the distributional ranges of troglomorphic species (as well as other subterranean-restricted taxa). Specifically, while nearly 40 percent of troglomorphic millipedes were identified as single cave endemics, 14 troglobionts (including one whose range was expanded from this work) occurred within two or more caves. One species, P. trifidus, was confirmed within three caves in the Guilin region (two caves from this work, plus the type locality); the maximum distance between caves for this species was 59.7 km. Three additional subterranean-adapted species occurred in multiple caves with maximum distances ranging from 81.27 and 137.6 km (Table
We also reported a possible ‘disturbance relict’, H. rukouqu sp. nov., discovered within a cave entrance vegetation community. As similar cave entrance vegetation communities have been identified as either supporting distinct relict plant communities and/or plant species in southern China (
Although caves are often considered distinct from the surface environment, cave ecosystems are inextricably linked to surface processes. Caves require an allochthonous energy supply, which may include flood detritus, guano deposition from bats, birds and crickets, and dissolved organic materials that percolate from the surface. Thus, when humans adversely change the surface environment, the cave ecosystem may change as well. Deforestation (
Despite the impressive biological diversity found in China, there are no government regulations, nor is any government agency responsible for managing and protecting cave resources. Development projects typically progress in caverniferous regions and tourist caves are developed without consideration for subterranean resources and the rich biodiversity they often support (
This paper revealed that at least 38 troglomorphic millipede species occur in Guangxi. Other examples of SCK’s high cave diversity includes at least 19 species of troglomorphic pseudoscorpions (
Dr. Wang Jietao at the Wuhan Center, China Geological Survey provided fieldwork and logistical support and developed part of figure 1. We thank International Research Center on Karst in Guilin for additional logistical support. Mr. Zhang Yuanhai provided us with information regarding regional caves while Dr. Qiang Li provided cave coordinates for some of the caves examined in this study. Dr. Wu Zhuoting offered additional assistance with some of the Mandarin names. Dr. Sergei Golovatch provided us with invaluable peer-review comments leading to the improvement of this manuscript. Fieldwork was recognized as an Explorers Club flag expedition. The lead author was sponsored by the National Natural Science Foundation of China (Grant no. 31801956 and Grant no. 41871039) for work related to species’ descriptions and manuscript preparation.