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. 2024 Mar 28;1196:285–301. doi: 10.3897/zookeys.1196.109810

A new loach species of the genus Oreonectes (Teleostei, Cypriniformes, Nemacheilidae) from Guangxi, China

Xue-Ming Luo 1, Rui-Gang Yang 2, Li-Na Du 1,✉, Fu-Guang Luo 3,✉
PMCID: PMC10995607  PMID: 38586077

Abstract

A new loach species, Oreonectesandongensissp. nov. is described from the Guangxi Zhuang Autonomous Region, China. The new species can be differentiated from other members of the genus by combinations of characters: a developed posterior chamber of the swim bladder, 13–14 branched caudal-fin rays, 8–16 lateral-line pores, body width 12–15% of standard length (SL), interorbital width 42–47% of head length (HL), and caudal peduncle length 11–16% of SL. Bayesian inference phylogenetic analysis based on mitochondrial Cyt b provided strong support for validity of O.andongensissp. nov. (uncorrected p-distance 6.0–7.5%).

Key words: New species, morphology, phylogeny, taxonomy, Xijiang River

Introduction

The freshwater fish genus Oreonectes Günther, 1868, which belongs to the family Nemacheilidae, exhibits notable adaptations to the karst geomorphic environment. These small fish are predominantly distributed in southern China (Xijiang River system of Guangxi Zhuang Autonomous Region, Pearl River system of Guangdong Province, and Pearl River system of Hong Kong) and Kalong River of northern Vietnam (Quảng Ninh Province in northeast Vietnam) (Kottelat 2012). The genus was first established by Günther in 1868, designating Oreonectesplatycephalus Günther, 1868 as the type species, collected from a small stream in Hong Kong within the Pearl River system. The diagnosis of the genus included a slightly compresses body, a markedly depressed head, and the origin of the dorsal fin much closer to the base of the caudal fin than to the operculum Günther (1868). Later, till 2006 a number of species have been added to the genus: O.anophthalmus Zheng, 1981 (an underground river in Taiji Cave, Wuming County, Guangxi, Youjiang River, China), O.furcocaudalis Zhu & Cao, 1987 (a subterranean water outlet in the suburbs of Rongshui County, Guangxi, Liujiang River, China), O.retrodorsalis Lan, Yang & Chen, 1995 (an underground river outlet in Longli Village, Nandan County, Guangxi, Hongshui River, China), and O.translucens Zhang, Zhao & Zhang, 2006 (Xia’ao Town, Du’an County, Guangxi, Hongshui River, China) (Zheng 1981; Zhu 1989; Lan et al. 1995; Zhang et al. 2006). Subsequently, a revision of Oreonectes was published with description of two new species O.microphthalmus Du, Chen & Yang, 2008 (Du’an County, Guangxi, Hongshui River, China) and O.polystigmus Du, Chen & Yang, 2008 (Dabu Village, Guilin City, Guangxi, Lijiang River, China) (Du et al. 2008). Meanwhile, Du et al. (2008) subdivided the genus into two groups based on the caudal fin morphology: the round caudal fin group (O.platycephalus group), containing O.anophthalmus, O.platycephalus, O.polystigmus, and O.retrodorsalis, and the forked caudal fin group (O.furcocaudalis group), including O.furcocaudalis and O.microphthalmus. After 2009, various species were described, including O.macrolepis Huang, Du, Chen & Yang, 2009 (an underground river in Dacai Town, Huanjiang County, Guangxi, Xijiang River system, China), O.luochengensis Yang, Wu, Wei & Yang, 2011 (a cave near Tianhe Town, Luocheng County, Guangxi, Xijiang River system, China), O.guananensis Yang, Wei, Lan & Yang, 2011 (an underground karst cave outlet near Guan’an Village, Changmei Town, Huanjiang County, Guangxi, Xijiang River system, China), O.elongatus Tang, Zhao & Zhang, 2012 (Mulun Town, Huanjiang County, Guangxi, Longjiang River, China), O.acridorsalis Lan, 2013 (a cave near Bamu Town, Tian’e County, Guangxi, Hongshui River, China), O.barbatus Gan, 2013 (first described from a cave near Lihu Town, Nandan County, Guangxi, Hongshui River, China), O.donglanensis Wu, 2013 (a cave near Simeng Town, Donglan County, Guangxi, Hongshui River, China), O.duanensis Lan, 2013 (a cave near Chengjiang Town, Du’an County, Guangxi, Hongshui River, China), O.daqikongensis Deng, Xiao, Hou & Zhou, 2016 (Seven Big Scenic Spot, Libo County, Guizhou, Hongshui River, China), O.shuilongensis Deng, Wen, Xiao & Zhou, 2016 (a cave near Shuilong Town, Sandu County, Guizhou, Duliu River, China), O.guilinensis Huang, Yang, Wu & Zhao, 2020 (Shigumen Village, Xingping Town, Yangshuo County, Guilin City, Guangxi, Lijiang River, China), and O.damingshanensis Yu, Luo, Lan, Xiao & Zhou, 2023 (Waminggu Scenic Area, Leping Village, Guling Town, Mashan County, Guangxi, Xijiang River system, China) (Huang et al. 2009, 2020; Yang et al. 2011a, b; Tang et al. 2012; Lan et al. 2013; Deng et al. 2016a, b; Yu et al. 2023). Zhang et al. (2016) established the genus Troglonectes Zhang, Zhao & Tang, 2016, designating O.furcocaudalis as the type species, with O.barbatus, O.elongatus, O.macrolepis, O.microphthalmus, and O.translucens, characterized by a forked caudal fin, a developed adipose crest of the caudal fin, and the dorsal-fin origin above the pelvic-fin origin. Later studies added O.daqikongensis, O.donglanensis, O.duanensis, O.retrodorsalis, and O.shuilongensis to Troglonectes (Huang et al. 2020; Du et al. 2023), while O.anophthalmus and O.acridorsalis were assigned to a new genus, Karstsinnectes Zhou, Luo, Wang, Zhou & Xiao, 2023 based on morphological and molecular evidence (Luo et al. 2023).

Until now, the genus of Oreonectes contains six valid species, namely, O.damingshanensis, O.guananensis, O.guilinensis, O.luochengensis. O.platycephalus, and O.polystigmus. In July 2022, ten loach specimens were collected from Laibin City in the Hongshui River system, Guangxi Zhuang Autonomous Region, China. Morphological features and molecular data suggest that the specimens under consideration represent a previously undescribed species within the genus Oreonectes, which are described herein.

Materials and methods

Field collections followed the Guide to Collection, Preservation, Identification, and Information Share of Animal Specimens (Xue 2010) and Implementation Rules of Fisheries Law of the People’s Republic of China. All activities followed the Laboratory Animal Guidelines for the Ethical Review of Animal Welfare (GB/T 35892–2018). Specimens of the new species were collected by FGL. Samples were collected using a hand net and mesh traps. Freshly caught fish were euthanized using eugenol. After death, the pectoral fins from the right side were taken and preserved in ethanol for molecular analysis. Specimens used for morphological studies were preserved in 10% formalin, before being transferred to 75% ethanol for long-term storage at the collection of the Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education.

Phylogenetic analyses

Mitochondrial cytochrome b gene (Cyt b) sequences were sequenced by the Science Corporation of Gene (China) following standard Illumina protocols. Genome sequencing data were submitted to GenBank (Accession No. OR188128, OR712240, OR712241). We retrieved 36 Cyt b sequences of Nemacheilidae species from the NCBI GenBank database (Appendix 1) for phylogenetic tree reconstruction to test the phylogenetic positions of Oreonectesandongensis sp. nov. All sequences were aligned in MEGA v. 11.0 (Tamura et al. 2021) by the MUSCLE (Edgar 2004) algorithm with default parameters, and then sequences were executed in PartitionFinder v. 2.1.1 (Lanfear et al. 2017) in order to select the most appropriate model of evolution to be used for phylogenetic analyses. The model selection for each codon position of the complete mitochondrial genes indicated that the best fit models were K80+I+G for the first codon, HKY+I+G for the second codon, and TRN+I+G for the third codon. Bayesian inference (BI) analysis was performed using MRBAYES v. 3.2.6 (Ronquist et al. 2012). The chains were run for two million generations and sampled every 1000 generations. The first 25% of the sampled tree was discarded as burn-in, and the remaining trees were used to create a consensus tree and to estimate Bayesian posterior probabilities (BPP). Nodes in the trees were considered well-supported at BPP ≥ 0.95.

Morphological examination

Methods used for counts and measurements followed Du et al. (2021) and characteristics of the cephalic lateral line system were examined following Kottelat (1990) and Tang et al. (2012). All measurements were taken point-to-point with dial calipers to the nearest 0.1 mm. Abbreviations used in the text are as follows: AFBL for anal-fin base length, AFL for anal-fin length, BD for body depth, BW for body width, CPL for caudal peduncle length, CPD for caudal peduncle depth, DAPN for distance between anterior and posterior nostrils, DAN for distance between anterior nostrils, DFBL for dorsal-fin base length, DFL for dorsal-fin length, DPN for distance between posterior nostrils, ED for eye diameter, HD for head depth, HL for head length, HW for head width, ISBL for inrostral barbel length, IW for interorbital width, MBL for maxillary barbel length, OSBL for outrostral barbel length, PANL for preanus length, PAL for preanal length, PDL for predorsal length, PFBL for pectoral-fin base length, PFL for pectoral-fin length, PPL for prepectoral length, PVL for prepelvic length, STL for snout length, SL for standard length, TL for total length, VFBL for pelvic-fin base length, and VFL for pelvic-fin length.

Results

Genetic evidence from phylogenetic analysis

BI analyses were performed to construct a phylogenetic tree, revealing consistent topologies based on Cyt b sequences spanning 1141 bp. The phylogenetic tree affirmed the validity of the new species with high nodal support (BPP ≥ 0.95). Additionally, members of the Oreonectes genus constituted a monophyletic group, which was phylogenetically sister to the GuinemachilusDu et al., 2023 and Micronemacheilus clade (Fig. 1). Oreonectesandongensis sp. nov. formed a highly supported clade with O.damingshanensis, O.guilinensis, O.platycephalus, and O.polystigmus.

Figure 1.

Figure 1.

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Bayesian phylogenetic tree of Oreonectes based on mitochondrial Cyt b. Numbers above branches are BPPs.

The uncorrected p-distances of Cyt b between Oreonectesandongensis sp. nov. and the other six species ranged from 6.0% (for O.polystigmus) to 7.5% (for O.guananensis) (Table 2).

Table 2.

Uncorrected p-distances (%) between seven species in the genus Oreonectes based on mitochondrial Cyt b genes.

ID Species 1 2 3 4 5 6
1 Oreonectesandongensis sp. nov.
2 Oreonectesdamingshanensis 6.1
3 Oreonectesguananensis 7.5 8.7
4 Oreonectesguilinensis 7.0 7.2 8.8
5 Oreonectesluochengensis 6.4 7.5 4.8 8.1
6 Oreonectesplatycephalus 6.6 6.7 8.7 6.5 7.9
7 Oreonectespolystigmus 6.0 6.0 8.3 7.3 7.4 6.4
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Taxonomy

. Oreonectes andongensis

Luo, Yang, Du & Luo sp. nov.

BFECA430-0E51-5032-9598-614CC3D910AB

https://zoobank.org/31E2362E-71AF-4E1F-B78A-53DFB1980F33

Table 1 , Figs 1 , 2 , 3 , 4 , 5

Table 1.

Morphological data and habitat types of the genus Oreonectes. Data of O.damingshanensis is from the original description (Yu et al. 2023).

O.andongensis sp. nov. O.damingshanensis O.guananensis O.guilinensis O.luochengensis O.platycephalus O.polystigmus
Range (Mean ± SD) Range (Mean ± SD) Range (Mean ± SD) Range (Mean ± SD) Range (Mean ± SD) Range (Mean ± SD) Range (Mean ± SD)
TL (mm) 45.9–74.9 (57.1 ± 9.9) 63.7–98.9 (78.8 ± 8.8) 62.9–90.2 (75.7 ± 10.5) 63.2–89.7 (80.4 ± 7.6) 77.2–92.1 (84.2 ± 4.8) 49.6–82.5 (65.2 ± 11.7) 41.8–67.8 (52.2 ± 8.0)
SL (mm) 36.5–60.2 (46.2 ± 8.4) 52.5–81.8 (64.9 ± 7.3) 51.0–71.5 (60.9 ± 8.3) 52.0–73.5 (65.9 ± 6.1) 62.2–74.7 (68.1 ± 4.3) 38.7–64.2 (51.2 ± 9.3) 33.7–54.7 (42.5 ± 6.7)
Percentage of SL (%)
BD 15.7–17.9 (16.7 ± 0.7) 14.2–18.1 (15.5 ± 1.3) 16.2–19.6 (17.6 ± 1.3) 16.7–18.5 (18.0 ± 0.5) 16.0–18.3 (17.3 ± 0.7) 14.8–19.3 (17.2 ± 1.4) 12.5–19.5 (16.3 ± 2.2)
BW 11.5–15.2 (12.7 ± 1.0) 10.4–12.5 (11.3 ± 0.6) 9.5–13.1 (11.3 ± 1.3) 12.7–14.8 (13.9 ± 0.6) 9.8–12.1 (10.8 ± 0.8) 9.5–11.5 (10.5 ± 0.5) 7.4–11.8 (8.7 ± 1.2)
HW 14.7–17.2 (15.7 ± 0.7) 14.4–17.8 (16.1 ± 1.0) 14.8–16.9 (15.9 ± 0.7) 15.4–19.0 (17.0 ± 1.1) 13.7–16.9 (14.9 ± 0.9) 14.6–17.5 (15.7 ± 0.8) 13.7–17.5 (15.5 ± 1.2)
HD 11.4–12.8 (12.1 ± 0.5) 10.8–12.9 (12.0 ± 0.7) 10.9–11.9 (11.4 ± 0.4) 12.0–15.2 (13.3 ± 1.0) 10.0–12.4 (11.1 ± 0.7) 10.3–13.5 (11.3 ± 0.9) 11.1–13.1 (12.1 ± 0.7)
HL 21.1–24.5 (22.3 ± 0.9) 20.2–23.0 (21.7 ± 0.9) 21.8–23.2 (22.6 ± 0.5) 20.3–24.2 (21.7 ± 1.1) 20.7–24.2 (22.4 ± 1.0) 20.8–25.4 (22.8 ± 1.4) 22.3–24.5 (23.6 ± 0.6)
PDL 57.7–62.4 (60.0 ± 1.7) 59.5–62.4 (60.7 ± 0.8) 57.2–59.5 (58.4 ± 0.8) 57.4–60.4 (58.9 ± 0.9) 58.0–63.3 (60.0 ± 1.5) 60.0–64.7 (62.0 ± 1.9) 59.2–63.9 (60.9 ± 1.6)
DFL 16.8–19.2 (18.1 ± 0.7) 17.2–21.7 (18.9 ± 1.2) 17.6–18.6 (18.0 ± 0.3) 16.6–19.0 (17.4 ± 0.8) 16.9–19.2 (18.2 ± 0.7) 15.7–21.1 (19.4 ± 1.6) 16.8–19.8 (18.1 ± 1.0)
DFBL 8.9–11.6 (10.4 ± 0.8) 9.0–11.3 (10.3 ± 0.7) 9.5–11.0 (10.1 ± 0.6) 7.2–10.4 (8.8 ± 0.9) 6.6–7.3 (7.0 ± 0.3) 9.4–11.1 (10.1 ± 0.5) 8.9–12.1 (10.0 ± 1.0)
PPL 19.4–23.7 (21.2 ± 1.2) 19.1–22.7 (21.4 ± 1.0) 21.4–23.0 (22.0 ± 0.5) 16.9–20.4 (19.1 ± 1.2) 19.0–21.8 (20.3 ± 0.7) 18.1–22.4 (21.1 ± 1.6) 19.2–25.2 (22.0 ± 1.6)
PFL 15.1–18.9 (16.7 ± 1.0) 15.5–18.7 (16.9 ± 1.1) 14.5–17.1 (16.1 ± 0.9) 14.2–16.0 (15.3 ± 0.6) 15.3–18.5 (17.1 ± 1.0) 15.1–22.1 (19.3 ± 1.8) 13.5–19.4 (15.6 ± 1.7)
PFBL 3.2–4.3 (3.9 ± 0.3) 3.6–4.5 (4.0 ± 0.3) 3.4–4.5 (3.9 ± 0.4) 3.1–4.5 (3.9 ± 0.5) 4.0–5.6 (4.6 ± 0.5) 3.9–5.2 (4.5 ± 0.6) 2.7–4.5 (3.9 ± 0.5)
PVL 54.3–58.2 (56.1 ± 1.4) 48.6–52.2 (50.6 ± 1.0) 55.4–57.4 (56.5 ± 0.9) 53.8–55.8 (55.1 ± 0.8) 55.3–60.3 (56.3 ± 2.1) 52.2–56.4 (54.4 ± 1.7) 53.4–57.1 (55.1 ± 1.2)
VFL 11.1–13.6 (12.5 ± 0.8) 14.7–17.2 (15.8 ± 0.9) 14.5–17.1 (16.1 ± 0.9) 10.9–12.5 (11.8 ± 0.6) 11.9–14.7 (13.4 ± 0.9) 15.5–22.1 (19.3 ± 1.8) 12.1–15.7 (13.6 ± 1.2)
VFBL 3.0–4.0 (3.5 ± 0.4) 3.2–4.3 (3.8 ± 0.3) 3.0–4.2 (3.6 ± 0.4) 2.6–3.5 (3.2 ± 0.3) 3.1–3.9 (3.3 ± 0.2) 3.8–5.4 (4.5 ± 0.6) 2.7–4.0 (3.2 ± 0.4)
PAL 78.6–82.6 (80.0 ± 1.1) 74.6–77.9 (75.6 ± 1.0) 77.3–81.6 (80.6 ± 1.5) 78.4–81.2 (79.6 ± 0.9) 80.1–83.0 (81.3 ± 1.0) 77.6–80.5 (79.1 ± 1.0) 76.7–81.7 (79.9 ± 1.4)
AFL 14.3–17.7 (15.7 ± 1.1) 16.1–18.1 (16.9 ± 0.6) 14.2–16.1 (15.0 ± 0.6) 14.3–15.6 (14.6 ± 0.6) 14.0–16.8 (15.6 ± 0.8) 14.4–19.2 (17.8 ± 1.5) 14.9–17.2 (16.1 ± 1.0)
AFBL 6.8–8.1 (7.4 ± 0.5) 7.3–9.4 (8.4 ± 0.6) 6.7–7.5 (7.1 ± 0.3) 5.9–7.6 (6.8 ± 0.5) 6.6–7.3 (7.0 ± 0.3) 7.5–9.0 (8.1 ± 0.5) 7.1–11.0 (8.4 ± 1.2)
PANL 72.2–77.4 (74.1 ± 1.6) 78.6–82.8 (80.1 ± 1.2) 73.3–76.6 (74.6 ± 1.2) 71.7–74.2 (73.5 ± 0.9) 72.0–78.6 (74.1 ± 2.0) 71.2–76.1 (73.5 ± 1.6) 68.5–76.2 (73.8 ± 2.4)
CPL 11.2–15.5 (13.1 ± 1.3) 14.3–17.8 (15.7 ± 1.0) 11.5–13.4 (12.4 ± 0.6) 11.6–14.1 (12.2 ± 0.8) 10.1–12.5 (11.0 ± 0.8) 11.0–14.5 (12.6 ± 1.0) 10.2–14.3 (11.5 ± 1.2)
CPD 9.7–11.7 (10.6 ± 0.8) 10.0–11.6 (10.8 ± 0.5) 10.1–11.3 (10.8 ± 0.4) 9.5–11.3 (10.2 ± 0.6) 9.8–12.0 (10.7 ± 0.8) 12.2–14.8 (13.0 ± 0.9) 8.5–13.4 (10.9 ± 1.5)
Percentage of HL (%)
ED 13.6–19.5 (15.9 ± 1.7) 11.2–15.2 (12.4 ± 1.2) 10.4–14.9 (12.9 ± 1.7) 9.2–13.5 (10.9 ± 1.3) 9.0–14.2 (11.9 ± 1.6) 11.1–19.7 (15.1 ± 2.3) 12.5–16.8 (14.7 ± 1.7)
IW 41.8–47.3 (43.9 ± 1.7) 34.6–44.6 (41.3 ± 2.5) 42.3–47.9 (44.9 ± 2.1) 44.1–51.9 (48.1 ± 2.7) 39.9–45.2 (42.2 ± 2.1) 41.1–49.9 (46.1 ± 2.5) 34.5–45.6 (40.3 ± 3.2)
STL 30.2–34.7 (32.8 ± 1.6) 37.7–43.3 (40.7 ± 1.8) 31.2–40.2 (36.0 ± 3.3) 30.3–40.5 (35.1 ± 3.3) 33.5–40.5 (36.4 ± 2.0) 34.4–40.9 (37.3 ± 2.4) 31.2–37.9 (34.0 ± 2.0)
DAN 29.6–36.4 (33.0 ± 2.2) 23.6–39.2 (29.7 ± 3.9) 30.6–36.5 (34.1 ± 1.9) 29.1–35.6 (32.5 ± 2.3) 31.4–35.1 (32.8 ± 1.4) 31.6–38.0 (35.0 ± 2.6) 26.4–37.1 (30.4 ± 2.9)
DPN 34.0–39.1 (37.2 ± 1.8) 33.8–38.9 (36.5 ± 1.5) 34.5–40.5 (37.7 ± 1.9) 34.0–37.8 (36.0 ± 1.3) 33.8–38.2 (36.0 ± 1.7) 37.6–42.8 (39.3 ± 1.6) 34.3–41.6 (36.7 ± 2.3)
DAPN 8.0–11.1 (9.6 ± 0.9) 6.3–10.6 (7.7 ± 1.3) 8.2–13.2 (10.6 ± 2.0) 7.5–11.9 (10.5 ± 1.4) 8.0–13.0 (9.9 ± 1.7) 10.1–12.3 (11.0 ± 0.7) 8.1–12.4 (10.3 ± 1.6)
MBL 43.3–55.9 (48.0 ± 4.4) 36.4–50.8 (43.3 ± 4.7) 52.9–61.7 (56.1 ± 2.7) 37.3–55.4 (45.5 ± 5.3) 41.5–55.6 (46.0 ± 4.5) 38.3–56.3 (48.7 ± 5.3) 33.9–55.9 (45.5 ± 8.0)
OSBL 50.0–69.6 (59.4 ± 6.6) 47.4–58.7 (54.4 ± 4.4) 64.8–71.6 (68.8 ± 2.6) 41.3–52.5 (48.2 ± 5.6) 43.9–60.7 (51.5 ± 6.4) 47.2–66.5 (57.4 ± 5.8) 39.2–61.4 (53.9 ± 7.1)
ISBL 25.5–48.5 (38.2 ± 8.6) 25.6–37.4 (33.1 ± 3.4) 30.6–51.5 (42.1 ± 6.4) 28.8–36.9 (33.1 ± 2.9) 28.7–40.8 (33.1 ± 4.6) 35.9–40.6 (37.8 ± 2.6) 21.1–47.9 (33.1 ± 7.4)
Percentage of CPL (%)
CPD 67.2–98.7 (81.6 ± 8.9) 63.4–78.0 (68.7 ± 5.1) 75.1–97.5 (87.7 ± 6.8) 74.7–90.6 (83.3 ± 4.6) 95.2–118.2 (98.5 ± 10.1) 95.0–125.0 (103.4 ± 10.2) 73.8–131.0 (96.7 ± 20.5)
Habitat types Small pools on surface where groundwater overflowed Karst cave under mountain Water outlet of underground karst cave Open stream Water of underground karst cave Surface stream Underground karst cave
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Figure 2.

Figure 2.

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Oreonectesandongensis sp. nov. A–C lateral, dorsal and ventral views of holotype GXNU20220601 (♀), D lateral view of paratype GXNU20220610 (♂), E, F gonadal structure of female (E) and male (F).

Figure 3.

Figure 3.

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Stomach, anterior chamber, and posterior chamber of Oreonectesandongensis sp. nov.

Figure 4.

Figure 4.

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Distribution of Oreonectes in southern China.

Figure 5.

Figure 5.

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Habitat of Oreonectesandongensis sp. nov.

Type material.

Holotype. GXNU20220601, 74.9 mm standard length (SL), Andong Town, Xincheng County, Laibin City, Hongshui River system, Guangxi Zhuang Autonomous Region, China, 24°18.57'N, 108°59.61'E, 179 m a.s.l., collected by F.G.L., 20 July 2022. Paratypes. GXNU20220602–10, 9 specimens, 45.9–68.7 mm SL, same data as holotype.

Diagnosis.

The new species is assigned to the genus Oreonectes based on Cyt b phylogenetic analysis and morphological characters. The new species can be distinguished from other members of Oreonectes by the following combination of characters: posterior chamber of swim bladder developed (vs reduced in O.platycephalus), color pattern present (vs colorless in O.luochengensis), tip of pelvic fin not reaching anus (vs exceeding anus in O.polystigmus and O.guilinensis), dorsal-fin origin slightly posterior to pelvic-fin origin (vs opposite in O.guananensis), six branched pelvic-fin rays (vs 7 or 8 in O.damingshanensis, O.guananensis, O.luochengensis). Oreonectesandongensis sp. nov. can be further differentiated from O.damingshanensis by more numerous, better developed inner gill rakers on the first gill arch (11–12 vs 9).

Description.

The morphometric data of the holotype and paratypes are in Table 1. Three unbranched and seven branched dorsal-fin rays, one unbranched and nine or ten branched pectoral-fin rays, one unbranched and six branched pelvic-fin rays, three unbranched and five branched anal-fin rays, 13 or 14 branched caudal-fin rays, and 11 or 12 inner-gill rakers on first gill arch (in 3 specimens).

Body elongated and cylindrical, deepest body depth in front of dorsal-fin origin, deepest body depth 16–18% of standard length (SL). Head slightly depressed and flattened, maximum head width greater than deepest head height. Anterior and posterior nostrils adjacent, distance shorter than diameter of posterior nostril. Base of anterior nostril tube-shaped with elongated barbel-like tip; barbel longer than anterior nostril tube. Eyes normal, eye diameter 14–20% of head length (HL). Snout obtuse, snout length shorter than postorbital length. Mouth inferior, lips smooth, center of lower lip with notch. Three pairs of barbels, inner rostral barbel length 23–49% of HL, extending to the anterior margin of eye; outer rostral barbel length 50–70% of HL, extending to the posterior margin of eye; maxillary barbel length 43–56% of HL, not reaching to posterior margin of opercula.

Dorsal-fin origin slightly posterior to pelvic-fin origin. Predorsal length 58–62% of SL. Tip of pectoral fin not reaching half of distance between origin of pectoral and pelvic fins. Tip of pelvic fin not reaching anus. Short distance (two times eye diameter) between anal-fin origin and anus. Caudal fin straight. Caudal peduncle without adipose crests along both dorsal and ventral sides. Caudal peduncle depth 67–99% of caudal peduncle length. Whole body covered by scales except head. Lateral line incomplete, with 8–16 pores. Cephalic lateral line system developed, with 6–9 supraorbital pores, 3 + 8–10 infraorbital pores, three or four canal pores, and 6–8 pre-operculo-mandibular canal pores.

Stomach U-shaped. Swim bladder divided into two chambers, anterior chamber covered by dumbbell-shaped bony capsule, and posterior chamber developed with posterior extremely reaching below dorsal-fin origin.

Coloration.

In formalin-fixed specimens, dorsal surface and trunk of body yellowish, while abdomen appears grayish. Additionally, dorsal surface and flank with small spots or short bars. Dorsal and caudal fins with black speckles. Longitudinal stripe extending from gill opening to caudal peduncle in female, lacking in males.

Sexual dimorphism.

In reproductive season, males possess large genital papilla located immediately posterior to anus, unclear in females; gonad opens at end of fleshy prominence.

Distribution and habitat.

Oreonectesandongensis sp. nov. was collected from Andong Township, Xincheng County, Laibin City, Guangxi Zhuang Autonomous Region, China, a tributary of the Hongshui River in Xijiang River basin. During the rainy season, specimens were gathered from small pools on the surface where groundwater had overflowed. TroglonectescanlinensisLi et al., 2023 specimens were also collected from the same pool.

Etymology.

The nomenclature of this species is derived from the Chinese pinyin of Andong, the name of the village where the specimens were obtained. We suggest the Chinese common name as “安东岭鳅”.

Remarks.

Oreonectesandongensis sp. nov. can be distinguished from O.damingshanensis by the six branched pelvic-fin rays (vs 7), a dorsal-fin origin slightly posterior to pelvic-fin origin (vs posterior to pelvic-fin origin obviously), and 11 or 12 inner gill rakers on the first gill arch (vs 9), from O.guananensis by six branched pelvic-fin rays (vs 7 or 8), dorsal-fin origin slightly posterior to pelvic-fin origin (vs opposite to pelvic-fin origin), caudal with irregular black markings (vs without irregular black markings), and maxillary barbel not reaching to the gill cover (vs reaching to the gill cover), from O.guilinensis by lateral line pores 8–16 (vs 4–6), tip of pelvic fin not reaching to anus (vs exceeding to anus), and maxillary barbel not reaching to the opercula (vs reaching to posterior margin of the eye), from O.luochengensis by cephalic lateral line system present (vs absent), abdomen between pectoral-fin origin to pelvic-fin origin scaled (vs scaleless), from O.platycephalus by posterior chamber of swim bladder developed (vs reduced), dorsal-fin origin slightly posterior to pelvic-fin origin (vs posterior to pelvic-fin origin obviously), seven branched dorsal-fin rays (vs 8 or 9), and six branched pelvic-fin rays (vs 8), from O.polystigmus by tip of pelvic fin not reaching to anus (vs exceeding to anus), and maxillary barbel not reaching to the opercula (vs reaching to the pectoral-fin origin).

Key to species of the genusOreonectes

1 Body colorless O.luochengensis
– Color pattern present 2
2 Dorsal-fin origin opposite to pelvic-fin origin O.guananensis
– Dorsal-fin origin posterior to pelvic-fin origin 3
3 Tip of pelvic fin exceeding anus 4
– Tip of pelvic fin not reaching anus 5
4 Six branched dorsal-fin rays O.guilinensis
– Seven branched dorsal-fin rays O.polystigmus
5 Posterior chamber of swim bladder reduced O.platycephalus
– Posterior chamber of swim bladder developed 6
6 Six branched pelvic fin rays, 11 or 12 inner gill rakers on first gill arch Oreonectesandongensis sp. nov.
– Seven branched pelvic fin rays, 9 inner gill rakers on first gill arch O.damingshanensis
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Discussion

The distinct lineage of Oreonectesandongensis sp. nov. marked by an uncorrected p-distance of 6.0% from O.polystigmus, along with notable morphological differences, substantiates its validity as a new species. With the addition of the new species, the genus Oreonectes now comprises seven species: Oreonectesandongensis sp. nov., O.damingshanensis, O.guananensis, O.guilinensis, O.luochengensis, O.platycephalus, and O.polystigmus.

Oreonectesandongensis sp. nov. exhibited sexual dimorphism. Notably, males contained larger genital papilla located immediately posterior to the anus, with the gonads opening at the end of a fleshy prominence. Zhu (1989) noted that this structure may be related to the special breeding habits of Oreonectes. Additionally, most species of Oreonectes possess that developed posterior chamber of swim bladder except O.platycephalus. Zhu (1989) speculated that the posterior chamber of swim bladder related to adapting to habitat. Oreonectesandongensis sp. nov. and other congeneric species (except O.platycephalus) possess developed posterior chamber of swim bladder, and mainly habitat in pools surround subterrane river, but O.platycephalus inhabit in running water of upper reaches of the river.

Within the genus Oreonectes, O.platycephalus has a broader distribution, both within and beyond Guangxi, whereas the other species are exclusively found in Guangxi. In areas within Guangxi, O.platycephalus coexists with the other species, with their distribution overlapping along certain routes of O.platycephalus (Tang 2012). Wang (2022) suggested that the ancestors of the Nemacheilidae family in southwest China emerged around 26.19 million years ago (approximately the Late Oligocene). The uplift of the Tibetan Plateau led to the development of the Pearl River occurred concurrently (Zhang et al. 2022). This expansion towards the Pearl River Delta area likely facilitated the spread of Oreonectes. As the caves in southwest China continued to develop, some fish species entered these habitats, evolving traits suited to cave living, such as eye degeneration, loss of scales, and lack of pigmentation.

Comparative material

All specimens were collected from Guangxi; their measurements are given in Appendix 2.

Oreonectesguananensis, KIZ2010003067, holotype, 71.5mm SL, KIZ2010003068–072, paratypes, 5 ex., 51.0–71.9 mm SL, Guan’an Village, Changmei Town, Huanjiang County, Guangxi.

Oreonectesguilinensis, ASIZB208001, holotype, 73.5 mm SL, ASIZB208002–007, paratypes, 6 ex., 52.0–68.3 mm, Shigumen Village Xingping Town, Yangshuo County, Guilin City, Guangxi.

Oreonectesluochengensis, KIZ2010003073, holotype, 71.2 mm SL, KIZ2010003074–077, KIZ2010003242–244, paratypes, 7 ex., 61.3–74.7 mm SL, Tianhe Town, Luocheng County, Guangxi.

Oreonectesplatycephalus, KIZ2003007105–106, 63.2–64.2 mm SL, KIZ2003007110, 60.9 mm SL, KIZ2005006211–212, 38.7–43.1 mm SL, KIZ2005006214–216, 45.6–47.7 mm SL, 8 ex., Fenzhan Village, Jinxiu County, Guangxi.

Oreonectespolystigmus, KIZ2001004626, holotype, 54.7 mm SL, KIZ2002004627–634, paratypes, 9 ex., 33.7–52.4 mm SL, Dabu Village, Guilin City, Guangxi.

Supplementary Material

XML Treatment for Oreonectes andongensis

Acknowledgements

We are grateful to Ying-Nan Wang, Institute of Zoology, Chinese Academy of Sciences, Beijing (ASIZB) and Rui Min, Kunming Institute of Zoology, Chinese Academy of Sciences (KIZ) for providing Oreonectes specimens, Jun-Kai Huang for taking photographs of the new species, and Christine Watts for English correction and suggestions.

Appendix 1

Table A1.

Localities, voucher information, and GenBank numbers for all samples used in this paper.

Species Locality Voucher GenBank number
Triplophysanasobarbatula Libo County, Guizhou, China GZNU20190114001 ON116529
Triplophysabaotianensis Nanpanjiang River, Panzhou City, Guizhou, China GZNU20180421005 NC056365
Triplophysazhenfengensis Xingren County, Guangxi, China GZNU20180419002 NC063617
Traccatichthyspulcher Daxin County, Guangxi, China Tissue ID: GX1 ON116516
Traccatichthyszispi Hainan, China Tissue ID:HN01 ON116518
Traccatichthystaeniatus N/A N/A NC031581
Lefuanikkonis N/A N/A NC027662
Lefuacostata N/A N/A NC029385
Lefuaechigonia N/A N/A NC004696
Oreonectesplatycephalus Shenzhen City, Guangdong, China GZNU2020112501 ON116528
Oreonectesguilinensis Xingping Town, Yangshuo County, Guangxi, China N/A MN239094
Oreonectesdamingshanensis Leping Village, Guling Town, Mashan County, Guangxi, China GZNU20230216011 OQ754117
Oreonectesdamingshanensis Leping Village, Guling Town, Mashan County, Guangxi, China GZNU20230216012 OQ754118
Oreonectesdamingshanensis Damingshan Mountain, Shanglin County, Guangxi, China GZNU 2020112502 ON116496
Oreonectespolystigmus Dabu Town, Yanshan District, Guilin, Guangxi, China GZNU2020011501 ON116514
Oreonectesandongensis sp. nov. Andong Town, Xincheng County, Laibin City, Guangxi, China N/A OR188128
Oreonectesandongensis sp. nov. Andong Town, Xincheng County, Laibin City, Guangxi, China N/A OR712240
Oreonectesandongensis sp. nov. Andong Town, Xincheng County, Laibin City, Guangxi, China N/A OR712241
Oreonectesluochengensis Tianhe Town, Luocheng County, Guangxi, China GZNU2020011502 ON116495
Oreonectesguananensis Changmei Town, Huanjiang County, Guangxi, China GZNU2020073102 ON116507
Guinemachiluslongibarbatus Hechi City, Guangxi, China GZNU20210823001 ON148334
Guinemachiluspseudopulcherrimus Dongmiao Village, Du’An County, Hechi City, Guangxi, China D1925 OQ024375
Micronemacheiluscruciatus N/A N/A NC033960
Micronemacheiluspulcherrimus Duan County, Hechi City, Guangxi, China GZNU20210609004 ON116493
Karstsinnectesparva Ande Town, Jingxi City, Guangxi, China Tissue ID: JTQ02 ON116520
Karstsinnectesanophthalmus Leiping Town, Daxin County, Guangxi, China GZNU2019011310 ON116513
Karstsinnectesacridorsalis Bamu Town, Tiane County, Guangxi, China GZNU2020 ON116515
Troglonectestranslucens Xiaao Town, Duan County, Guangxi, China GZNU 2020082302 ON116510
Troglonectesmacrolepis Dacai Town, Huanjiang County, Guangxi, China GZNU2019122202 NC073129
Troglonectesmicrophthalmus Tianhe Town, Luocheng County, Guangxi, China GZNU2020041601 NC073127
Troglonectescanlinensis Andong Town, Xincheng County, Liuzhou City, Guangxi, China c FFL-2023 OQ129618
Troglonectesfurcocaudalis Yongle Town, Rongshui County, Guangxi, China GZNU2020042701 ON116512
Paranemachiluszhengbaoshani Duan County, Guangxi, China GZNU20210526001 ON116530
Paranemachiluschongzuo Daxin County, Chongzuo City, Guangxi, China N/A MW532082
Paranemachilusjinxiensis N/A N/A NC039380
Paranemachilusgenilepis N/A N/A MT845213
Yunnanilusanalis N/A N/A MW729320
Yunnaniluspleurotaenia N/A QT95 MW192447
Yunnanilusjiuchiensis Jiuchi County, Penzhou City, Sichuan, China N/A MW532080
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Appendix 2

Table A2.

Measurements of the eight species of Oreonectes. All units are in mm.

Species Voucher number TL SL BD BW HL HD HW ED IW STL PDL PPL PVL PAL PANL CPL CPD DFL DFBL PFL PFBL VFL VFBL AFL AFBL MBL OSBL ISBL DAN DPN DAPN
O.andongensis sp. nov. GXNU20220601 74.9 60.2 10.8 9.1 13.3 7.5 10.3 2.0 5.9 4.6 37.5 12.6 35.0 49.7 46.6 6.8 6.7 10.8 6.9 11.4 2.3 8.2 2.1 8.7 4.3 6.9 8.3 6.3 4.3 4.7 1.5
GXNU20220602 68.7 56.4 10.0 7.5 12.7 7.0 8.8 2.1 5.3 3.9 35.0 10.9 32.4 46.2 42.1 7.0 6.6 10.7 5.8 9.1 2.3 7.1 2.2 8.7 4.4 7.0 7.9 5.7 4.6 4.8 1.2
GXNU20220603 67.2 54.4 9.4 6.5 12.2 6.2 8.3 1.8 5.1 3.9 31.4 10.8 30.2 44.2 40.6 6.4 5.3 10.5 6.3 9.6 2.1 7.3 2.0 9.4 4.0 6.0 7.8 5.5 4.1 4.7 1.2
GXNU20220604 61.4 50.9 8.0 6.7 10.8 5.8 7.8 1.6 5.1 3.6 29.7 10.6 27.6 41.3 36.9 6.5 5.2 9.3 5.3 8.2 2.2 5.7 2.0 7.4 3.9 4.7 7.3 5.2 3.6 4.2 1.1
GXNU20220605 57.3 47.5 7.6 6.1 10.2 5.6 7.1 1.4 4.6 3.5 28.0 10.7 26.8 38.3 34.9 6.4 5.0 8.5 4.9 7.2 1.9 6.0 1.7 7.3 3.7 4.6 5.3 3.8 3.2 4.0 0.9
GXNU20220606 52.3 40.8 6.8 5.2 8.9 5.2 6.5 1.4 3.9 3.1 23.7 8.8 22.4 32.5 29.4 4.9 3.7 7.1 4.2 6.8 1.4 4.9 1.4 5.8 2.8 3.9 4.9 2.3 2.8 3.4 0.8
GXNU20220607 45.9 36.7 6.4 4.5 9.0 4.5 6.1 1.3 4.0 2.9 22.7 8.7 21.3 29.8 27.9 4.9 4.3 6.6 3.9 6.2 1.6 4.7 1.1 6.1 2.5 4.1 4.6 2.7 2.8 3.2 0.7
GXNU20220608 49.6 40.4 6.4 4.7 9.0 4.8 5.9 1.8 3.8 2.9 24.0 8.5 22.2 32.4 29.3 5.4 4.4 6.8 3.9 6.7 1.7 4.6 1.2 6.4 3.2 4.0 5.5 2.4 3.2 3.5 0.9
GXNU20220609 48.1 38.4 6.4 4.7 8.4 4.9 6.1 1.4 3.8 2.9 22.9 7.7 21.0 30.2 27.9 5.8 3.9 7.1 3.8 6.5 1.6 4.9 1.5 6.8 3.1 4.7 5.8 3.8 2.9 3.0 0.8
GXNU20220610 46.1 36.5 5.9 4.2 8.5 4.5 5.6 1.5 3.7 2.6 22.4 8.0 20.7 29.6 27.3 5.7 4.1 6.8 3.3 6.0 1.2 4.7 1.1 5.6 2.5 4.0 4.2 2.8 2.5 2.9 0.9
O.guananensis KIZ2010003067 90.2 71.5 11.8 8.7 16.6 8.3 11.3 1.8 7.4 5.2 41.6 15.7 41.0 58.3 52.8 9.6 7.2 12.7 6.8 11.6 2.8 8.8 3.0 10.5 5.3 9.1 11.3 7.8 5.1 5.7 1.4
KIZ2010003068 76.8 61.4 10.1 7.1 13.9 7.2 9.7 1.8 6.4 4.4 36.0 13.5 35.3 49.6 47.1 7.8 6.9 11.0 6.0 10.5 2.3 8.0 2.2 9.5 4.5 7.6 9.8 5.9 4.8 5.0 1.8
KIZ2010003069 69.6 56.3 9.9 5.3 12.3 6.3 8.3 1.7 5.9 5.0 33.5 12.2 31.2 45.7 41.3 6.8 6.1 10.0 5.4 8.9 2.1 7.6 1.9 8.5 4.0 7.6 8.8 6.3 4.3 4.7 1.2
KIZ2010003070 66.2 53.3 10.5 5.2 12.3 6.4 9.0 1.8 5.2 4.6 30.5 11.8 29.7 43.5 39.9 6.4 5.7 9.7 5.8 8.6 2.3 6.7 1.7 7.6 3.6 6.9 7.9 5.0 4.1 4.8 1.6
KIZ2010003071 62.9 51.0 9.7 6.1 11.2 5.8 8.4 1.6 5.2 4.2 29.3 10.9 28.3 39.4 37.7 6.5 5.5 9.5 5.6 8.7 1.7 6.3 2.1 8.2 3.8 5.9 7.4 3.4 4.1 4.5 0.9
KIZ2010003072 88.5 71.9 11.7 9.4 16.6 7.8 11.3 1.7 7.0 6.2 42.6 16.6 41.3 58.5 54.4 8.3 8.1 12.7 7.0 10.5 3.2 10.1 2.2 10.5 4.8 9.2 11.8 6.8 5.9 6.2 1.8
O.guilinensis ASIZB208001 89.7 73.5 12.3 9.3 16.0 10.3 12.2 1.6 7.8 6.1 43.4 38.6 39.9 39.7 40.0 31.4 38.3 12.2 6.8 10.7 2.7 9.0 2.2 10.9 4.3 7.1 7.4 4.6 5.7 6.0 1.9
ASIZB208002 81.4 67.3 12.3 9.1 14.1 8.1 10.7 1.3 7.0 5.0 15.0 12.9 13.8 12.0 11.4 10.2 12.6 12.8 5.9 10.5 2.9 8.4 2.3 10.1 5.1 6.9 7.4 5.2 4.1 4.8 1.5
ASIZB208003 82.8 68.3 12.4 10.1 14.8 9.1 12.1 2.0 7.5 6.0 40.4 37.0 38.1 37.5 36.4 29.1 35.4 11.6 6.3 10.9 3.1 8.3 2.2 9.8 4.8 8.2 6.7 4.4 5.1 5.6 1.7
ASIZB208004 83.8 67.1 12.4 9.7 14.5 9.0 11.7 1.5 6.7 4.4 59.7 54.2 53.7 53.2 53.0 41.3 52.3 12.0 4.8 10.3 2.1 7.3 2.3 9.8 4.2 6.0 7.7 5.1 4.8 5.0 1.7
ASIZB208005 82.2 67.6 12.4 9.3 14.3 8.2 10.4 1.7 6.3 4.5 54.4 49.8 49.0 48.7 49.7 38.6 48.6 11.5 5.5 9.6 2.9 7.9 2.2 9.7 4.6 6.4 5.9 4.5 4.9 5.1 1.4
ASIZB208006 63.2 52.0 9.5 7.4 12.6 7.9 9.9 1.3 5.7 4.4 8.8 7.8 8.5 7.9 9.5 6.3 7.6 8.7 5.4 8.0 2.0 6.3 1.8 8.1 3.8 4.7 5.3 4.4 3.8 4.5 1.3
ASIZB208007 79.6 65.5 11.8 9.1 13.3 8.6 11.0 1.5 6.9 4.6 7.3 6.4 7.7 6.9 7.1 5.1 6.4 11.4 5.6 10.5 2.2 7.2 1.7 8.8 4.5 6.1 7.6 4.6 4.1 4.9 1.0
O.luochengensis KIZ2010003073 86.0 71.2 11.4 7.4 14.7 11.6 10.7 2.1 6.0 5.5 42.5 14.4 39.4 58.2 52.8 7.3 8.6 13.0 7.5 10.9 2.9 8.5 2.2 11.4 5.0 6.1 7.3 4.4 5.0 5.6 1.4
KIZ2010003074 83.9 67.0 11.5 6.6 15.5 12.0 9.2 2.0 6.2 5.2 39.6 13.2 36.4 53.7 48.7 6.9 6.6 12.7 6.7 11.7 2.8 9.0 2.3 10.9 4.4 6.7 7.7 4.5 4.9 5.3 1.3
KIZ2010003075 86.3 68.8 11.8 7.8 15.3 12.5 10.4 1.8 6.7 5.8 41.8 14.2 38.4 55.7 50.3 7.8 7.5 13.2 6.9 12.7 3.1 10.1 2.4 11.6 4.9 8.5 9.3 6.2 5.2 5.8 1.2
KIZ2010003076 87.0 71.2 13.0 8.6 15.9 12.4 10.0 1.6 6.9 5.5 42.4 14.3 39.7 57.2 51.6 7.4 7.5 12.3 6.8 11.9 2.9 9.3 2.3 10.9 5.1 7.2 8.3 4.6 5.0 5.4 1.5
KIZ2010003077 77.2 62.2 10.7 6.7 15.1 11.7 10.5 2.0 6.7 5.4 37.8 13.6 37.5 51.3 48.9 7.0 7.1 11.4 6.3 10.8 3.0 8.2 1.9 9.6 4.6 7.5 9.4 5.6 5.0 5.2 2.0
KIZ2010003242 84.9 68.6 12.6 6.9 15.3 11.6 10.1 1.8 6.2 5.5 40.2 13.1 37.2 55.3 49.4 6.9 6.8 12.7 6.6 11.6 3.0 9.8 2.7 10.5 5.0 6.4 6.7 4.8 4.9 5.4 1.3
KIZ2010003243 92.1 74.7 12.9 8.9 16.6 13.1 11.5 1.5 7.5 6.1 47.2 15.2 44.4 62.0 55.5 8.7 8.7 12.6 7.3 12.0 3.6 9.3 2.4 10.5 4.9 7.2 7.4 4.8 5.2 6.0 2.1
KIZ2010003244 76.4 61.3 10.3 6.2 13.3 10.9 9.1 1.6 5.4 5.4 35.5 12.4 33.9 49.6 46.2 7.6 6.0 11.3 6.0 11.3 3.4 8.6 2.0 9.6 4.2 6.4 6.6 5.1 4.7 5.0 1.4
O.platycephalus KIZ2003007105 82.5 64.2 12.4 6.8 16.3 12.5 11.2 2.4 6.7 6.1 41.5 14.1 36.2 51.3 48.8 7.1 8.9 13.6 6.8 12.9 3.5 11.5 2.7 12.1 4.9 9.2 10.9 6.3 5.7 6.2 1.8
KIZ2003007106 80.1 63.2 12.0 6.0 13.2 11.0 9.9 1.9 5.9 4.6 41.1 14.4 35.7 50.6 46.5 7.7 7.9 12.0 6.4 11.5 2.5 9.7 2.1 10.5 5.2 6.9 8.2 5.3 4.9 5.1 1.6
KIZ2003007110 75.9 60.9 10.9 6.2 13.0 10.7 9.7 1.4 5.9 5.0 38.3 11.6 34.1 47.2 45.7 7.8 7.5 9.5 6.0 9.4 2.5 8.8 2.2 8.8 4.6 6.5 7.0 4.2 4.0 4.9 1.5
KIZ2005006211 56.7 43.1 7.2 4.6 10.5 8.6 7.0 1.5 5.0 4.3 26.7 9.6 22.8 34.5 31.7 6.3 5.8 8.5 4.1 8.5 1.9 7.6 1.6 8.2 3.7 5.4 5.5 4.2 4.0 4.3 1.2
KIZ2005006212 49.6 38.7 6.2 4.5 9.0 7.5 6.1 1.8 4.0 3.3 23.3 8.5 21.6 30.4 28.8 5.1 5.7 8.0 4.3 8.5 2.0 7.2 1.8 7.4 3.5 4.6 5.6 3.4 3.0 3.4 0.9
KIZ2005006214 56.9 46.5 6.9 4.7 10.4 8.5 7.2 1.7 5.0 4.2 28.4 8.4 24.6 36.3 33.3 5.6 5.8 9.5 4.6 9.1 1.8 7.7 1.8 8.4 3.7 4.8 4.9 4.1 3.9 4.1 1.1
KIZ2005006215 61.6 47.7 7.8 5.1 10.9 9.4 7.0 1.7 5.0 3.7 28.6 10.5 25.2 38.4 34.6 6.4 6.1 9.4 4.6 9.1 2.3 8.0 2.0 8.8 3.7 4.7 6.1 3.9 4.0 4.6 1.3
KIZ2005006216 58.0 45.6 7.8 4.8 10.0 8.2 6.7 1.5 5.0 3.5 27.4 9.2 23.8 35.9 32.5 5.5 5.5 8.8 4.5 9.3 2.1 8.0 1.8 8.2 3.8 3.8 5.8 3.7 3.2 4.0 1.0
O.polystigmus KIZ2001004626 67.8 54.7 10.5 6.5 12.9 7.2 9.6 1.7 5.9 4.5 33.1 11.6 30.9 44.1 39.9 5.6 7.3 10.1 6.0 8.3 2.0 7.0 1.7 8.6 4.3 6.5 7.9 4.7 4.8 5.4 1.1
KIZ2001004627 62.7 52.4 6.6 3.9 11.9 5.9 7.7 1.5 4.8 4.3 31.4 11.5 28.8 41.7 39.2 6.1 5.8 8.9 4.8 7.1 2.0 6.3 1.6 8.1 3.9 6.4 5.4 3.5 3.4 4.4 1.0
O.polystigmus KIZ2001004628 45.8 37.4 5.3 2.9 8.9 4.2 5.1 1.2 3.3 2.9 23.9 7.2 20.4 30.6 28.5 4.3 3.2 6.8 3.7 6.2 1.6 5.9 1.4 6.1 4.1 3.0 4.6 3.2 2.7 3.3 1.1
KIZ2001004629 51.9 42.5 7.5 3.2 9.5 5.1 5.9 1.6 3.8 3.3 25.6 9.2 22.9 32.5 29.1 6.1 4.2 7.5 4.2 7.0 1.8 5.2 1.1 6.8 3.6 4.9 5.5 3.1 2.9 3.3 1.2
KIZ2001004630 41.8 33.7 6.6 3.1 8.2 4.3 5.2 1.4 3.6 2.8 19.9 8.5 18.8 27.4 25.0 3.5 3.9 6.7 3.6 5.3 1.5 4.9 1.0 5.0 2.6 2.9 4.6 1.7 2.7 3.2 0.7
KIZ2001004631 44.5 36.0 5.8 3.0 8.6 4.6 5.9 1.4 3.4 3.3 21.8 8.3 20.6 28.9 27.5 4.0 4.3 6.1 3.2 5.2 1.5 4.5 1.4 5.4 2.6 3.5 4.9 2.7 2.3 3.0 1.1
KIZ2001004632 49.5 39.9 6.9 3.5 9.6 5.1 6.2 1.2 3.8 3.0 25.5 9.3 21.3 32.0 30.1 4.7 3.8 7.1 3.6 5.6 1.1 5.9 1.1 6.9 3.9 3.7 3.8 2.4 2.8 3.5 0.9
KIZ2001004633 51.0 41.2 6.6 3.7 9.9 4.9 6.3 1.6 3.4 3.4 24.5 8.5 22.7 32.8 29.2 4.2 5.0 8.1 4.0 8.0 1.7 5.9 1.2 7.5 3.3 5.0 6.1 4.7 3.0 3.5 1.0
KIZ2001004634 55.2 44.4 6.6 4.0 10.5 5.6 7.4 1.5 4.5 3.3 26.8 10.0 24.4 35.3 33.4 5.2 4.3 7.8 5.4 7.0 1.9 6.0 1.6 7.4 4.0 5.9 5.8 4.1 3.0 3.6 1.1
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Luo X-M, Yang R-G, Du L-N, Luo F-G (2024) A new loach species of the genus Oreonectes (Teleostei, Cypriniformes, Nemacheilidae) from Guangxi, China. ZooKeys 1196: 285–301. https://doi.org/10.3897/zookeys.1196.109810

Funding Statement

Guangxi Natural Science Foundation Project (2022GXNSFAA035563 and 2020GXNSFAA238031), Ministry of Education, China (ERESEP2022Z05), Nanling biodiversity conservation priority area (Liuzhou area), Guangxi (11N00760329320231202).

Contributor Information

Li-Na Du, Email: dulina@mailbox.gxnu.edu.cn.

Fu-Guang Luo, Email: luofuguang3563@163.com.

Additional information

Conflict of interest

The authors have declared that no competing interests exist.

Ethical statement

No ethical statement was reported.

Funding

This study was funded by the Guangxi Natural Science Foundation Project (2022GXNSFAA035563 and 2020GXNSFAA238031), Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, China (ERESEP2022Z05), and Biodiversity Survey and Assessment Project Conducted in the Nanling Biodiversity Conservation Priority Area (Liuzhou area), Guangxi (11N00760329320231202).

Author contributions

XML measured the specimens, analyzed the data, constructed the phylogenetic tree, and prepared the manuscript; RGY provided the funding for the field survey; LND conceived and designed the study and reviewed the manuscript before submission; FGL conducted field surveys and provided funding for complete mitochondrial genomes. All authors have read and agreed to the published version of the manuscript.

Author ORCIDs

Xue-Ming Luo https://orcid.org/0000-0001-6441-4817

Li-Na Du https://orcid.org/0000-0002-2246-643X

Data availability

All of the data that support the findings of this study are available in the main text or Supplementary Information.

References

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Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

XML Treatment for Oreonectes andongensis
zookeys.1196.109810-treatment1.xml (51.8KB, xml)

Data Availability Statement

All of the data that support the findings of this study are available in the main text or Supplementary Information.

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