Biodiversity Data Journal :
Taxonomy & Inventories
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Corresponding author: Guangyu Li (liguangyu@mail.hzau.edu.cn)
Academic editor: Yahui Zhao
Received: 26 Mar 2024 | Accepted: 29 May 2024 | Published: 19 Jun 2024
© 2024 Peng Shan, Guangyu Li, E Zhang
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:
Shan P, Li G, Zhang E (2024) Sinobdella longitubulus, a new species of spiny eel (Pisces, Mastacembelidae) from the Zhu-Jiang Basin, with a note on the type locality of S. sinensis (Bleeker, 1870). Biodiversity Data Journal 12: e123990. https://doi.org/10.3897/BDJ.12.e123990
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The spiny eel genus Sinobdella belongs to the family Mastacembelidae of the order Synbranchiformes. Kottelat and Lim (1994) utilised Rhynchobdella sinensis as the type species to propose the genus. Currently, it contains a single species widespread in eastern and southern China and northern Vietnam.
Sinobdella longitubulus, a new species of spiny eel, is here described from the Xi-Jiang of the Zhu-Jiang Basin in Guangxi Zhuang Autonomous Region, southern China. It differs from the single congeneric species S. sinensis in having a more or less white-brown reticulated pattern on the flank, two tubular anterior nostrils longer than or equal to the rostral appendage, an anal fin heavily mottled with dark brown markings and white spots and bearing a narrow white distal margin; shorter pre-anal length; and fewer abdominal vertebrae. The validity of this new species is corroborated by its monophyly recovered in a COI gene-based phylogenetic analysis and its significant sequence divergence with S. sinensis. A note on the type locality of S. sinensis is also given; its type specimen is possibly from mountain streams of Jiangxi Province, in the lower Chang-Jiang Basin.
Sinobdella, new species, taxonomy, Zhu-Jiang Basin
The family Mastacembelidae, widely known as spiny eels, consists of anguilliform percomorph fishes, characterised by continuous dorsal spines along the mid-line dorsal body. These species are extensively distributed in tropical Africa, the Middle East and South and Southeast Asia, where they inhabit diverse freshwater environments such as lakes, streams and rivers, feeding on zooplankton, aquatic insect larvae and small fish (
The generic placement and specific status of the single species S. sinensis (Bleeker 1870a) have ever remained contentious. It was initially described in Rhynchobdella Bloch & Schneider and later referred to either Mastacembelus Scopoli (
The taxonomy of S. sinensis is still poorly understood due to a lack of information on its precise type locality. The original description stated that this species was from China, but without specifying its accurate location (
The specimens of Sinobdella used in this study were obtained via field sampling, in accordance with the Chinese Laboratory Animal Welfare and Ethics animal welfare laws (GB/T35892–2018). Some caught individuals after being anaesthetised were stored in 10% formalin for morphological observation and permanent curation, following the removal of a small flip of pectoral fin preserved in 95% ethanol. Other individuals were directly preserved in 95% ethanol or 10% formalin after being anaesthetised. Examined specimens are housed in the Museum of the Institute of Hydrobiology (IHB), Chinese Academy of Sciences, Wuhan City, Hubei Province, P. R. China, British Museum of Natural History (BMNH) and the Muséum national d'Histoire naturelle (MNHN).
Measurements were taken point to point with a digital caliper linked directly to a data-recording computer and data recorded to the nearest 0.1 mm. Measurements were made on the left side of specimens whenever possible. The counts of vertebra, dorsal spine and dorsal- and anal-fin rays were taken from X-ray photographs. Pectoral- and caudal-fin rays are difficult to count in a dissecting scope and, thus, not included here. All counts and measurements follow
Total genomic DNA was extracted from the pectoral fin stored in 95% ethanol using the TIANamp Genomic DNA Kit (Tiangen Biotech Co., Ltd, Beijing, China) following the manufacturer's recommendations. The mitochondrial cytochrome C oxidase subunit I (COI) gene was chosen for phylogenetic analysis. Amplification and sequencing of the target gene were achieved using the COI-F1 primer (5′GTGGCAATCACACGTTGAT′3) (
The amplified 136 gene sequences were used for molecular phylogenetic analysis along with other GenBank-retrieved sequences of the same gene from four outgroup species: Monopterus albus (
All the sequences in this study were retrieved from GenBank and the accession numbers of the newly-determined sequences in this study are shown in Suppl. material
Morphometric measurements and counts are presented in Table
S. sinensis (n = 32) |
S. longitubulus |
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Range |
Mean±SD |
Holotype |
Paratypes (n = 12) |
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Range |
Mean±SD |
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Morphometric measurements |
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Standard length, SL (mm) |
104.8-215.3 |
159.1±26.2 |
153.6 |
145.5-166.3 |
153.9±9.2 |
%of SL |
|||||
Head length |
14.0-16.9 |
15.6±0.7 |
15.8 |
14.1-16.0 |
14.7±0.6 |
Body width |
4.8-6.4 |
5.7±0.4 |
5.9 |
4.8-6.5 |
5.7±0.5 |
Body depth at anus |
8.1-10.4 |
9.3±0.6 |
9.4 |
7.8-10.4 |
9.0±0.7 |
Pre-anal length |
56.3-60.6 |
58.1±1.2 |
55.7 |
53.3-56.2 |
55.1±1.1 |
Post-anal length |
39.4-44.9 |
42.0±1.3 |
44.3 |
41.3-44.6 |
43.6±1.0 |
Soft dorsal-fin base length |
27.3-32.7 |
30.9±1.5 |
30.0 |
27.1-31.1 |
29.0±1.1 |
Soft anal-fin base length |
28.5-34.0 |
32.0±1.5 |
33.2 |
30.1-33.2 |
31.6±1.0 |
Snout to first dorsal spine |
17.7-23.3 |
20.1±1.2 |
21.9 |
18.7-22.1 |
20.2±1.1 |
Snout to last dorsal spine |
66.5-72.0 |
69.0±1.4 |
71.1 |
66.8-72.5 |
70.1±1.8 |
Snout to first anal spine |
58.2-64.0 |
60.8±1.5 |
58.4 |
56.1-59.9 |
58.7±1.2 |
Snout to last anal spine |
64.9-71.9 |
68.3±1.5 |
67.4 |
65.2-68.5 |
67.1±1.1 |
Dorsal end of pectoral-fin base to last dorsal spine |
51.8-56.0 |
54.3±1.0 |
55.1 |
52.4-57.6 |
55.2±1.5 |
First dorsal spine to last dorsal spine |
45.3-51.7 |
49.1±1.5 |
49.2 |
47.7-53.5 |
50.1±1.8 |
First anal spine to last anal spine |
6.0-8.3 |
7.2±0.6 |
8.6 |
7.3-8.6 |
8.2±0.4 |
% of HL |
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Snout length |
25.2-30.1 |
27.3±1.3 |
25.0 |
23.3-26.2 |
24.7±0.9 |
Eye diameter |
7.7-12.3 |
10.6±1.1 |
11.8 |
10.6-14.5 |
12.1±1.1 |
Minimum interorbital distance |
7.4-12.5 |
9.6±1.1 |
11.9 |
10.1-13.7 |
12.0±1.3 |
Postjaw angle length |
67.0-76.6 |
72.5±2.5 |
66.8 |
69.8-76.2 |
73.3±2.2 |
Postorbital length |
59.3-67.3 |
63.4±2.1 |
64.4 |
59.3-66.2 |
64.2±1.9 |
Post preorbital spine length |
62.8-76.4 |
68.9±2.9 |
68.4 |
64.8-71.5 |
67.1±2.3 |
Postorbital to preoperculum |
24.4-30.3 |
27.2±1.4 |
30.4 |
25.1-30.5 |
28.4±1.9 |
Snout to preoperculum |
57.9-67.7 |
63.2±2.5 |
65.5 |
56.1-68.9 |
64.7±3.7 |
Upper jaw length |
24.1-31.8 |
28.4±1.6 |
31.6 |
26.3-31.9 |
29.0±1.8 |
Lower jaw length |
19.9-27.0 |
24.3±1.6 |
27.9 |
21.6-28.3 |
25.0±2.1 |
Pectoral-fin length |
18.0-26.2 |
22.3±2.2 |
24.4 |
21.8-25.4 |
23.6±1.2 |
Dorsal end of pectoral-fin base to first dorsal spine origin |
22.9-35.4 |
29.8±3.3 |
32.3 |
28.1-38.6 |
34.3±3.5 |
Meristic counts |
S. sinensis (n=57) |
S. longitubulus (n=10) |
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Abdominal vertebrae |
34(13),35(25),36(19) |
33 |
32(1),33(8) |
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Vertebrae between first anal spine and last dorsal spine supporting pterygiophores |
6(9),7(38),8(10) |
8 |
8(8),9(1) |
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Caudal vertebrae |
40(2),41(5),42(15),43(14),44(10),45(8),46(2),47(1) |
43 |
43(6),44(2),45(1) |
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Vertebrae total |
76(11),77(15),78(8),79(12),80(8),81(5) |
76 |
76(7),77(2) |
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Dorsal spines |
31(4),32(13),33(19),34(21) |
33 |
32(1),33(8) |
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Dorsal-fin rays |
54(2),55(1),56(3),57(2),58(6),59(7),60(7),61(8), 62(6),63(2),64(4),65(3),66(3),67(2),68(1) |
55 |
51(1),52(2),53(1),54(1),55(1),56(1),57(1),58(1) |
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Anal-fin rays |
53(1),55(2),56(2),57(3),58(7),59(3),60(11),61(5), 62(6),63(5),64(4),65(2),66(1),67(2),68(1),69(2) |
58 |
51(2),52(1),53(3),57(1),58(2) |
Lateral views of freshly caught individual of two species of Sinobdella.
Body elongated, oval in cross-section and compressed laterally in caudal region. Body depth evenly deep towards soft anal-fin origin, then gradually decreasing towards caudal-fin base, terminating in form of a pointed or rounded fin tail-like structure. Tail region relatively short. Pre-anal length slightly greater than postanal length. Body covered with tiny scales without lateral line.
Head short and pointed, with snout produced into fleshy and long rostral appendage projecting from upper jaw. Two tubular anterior nostrils located on underside of rostral appendage, longer than or equal to this appendage. Posterior nares oval, horizontal axis longest and situated in front of eyes. Eyes small, laterodorsally located at anterior half of head. Posteriorly growing single pre-orbital spine on right/left side of head, located under eyes and buried under skin, with ending point extending beyond anterior margin of eye, but not reaching middle of eye. Mouth inferior and horse-shoe-shaped. Lips thick and fleshy. Jaws with numerous small, pointed teeth; upper jaw longer than lower jaw. Angle of jaws between the posterior edge of the posterior external nare and the anterior edge of the eye. Preoperculum unarmed. Upper extremity of gill opening immediately above dorsal end of pectoral-fin base, slightly anterior to vertical through ventral end of pectoral-fin base.
Dorsal fin long and divided into two parts: dorsal spines and dorsal-fin. Dorsal spines 32 to 33, increasing in size from first to second last spine; last spine smaller than second last spine, situated anterior to base of first soft dorsal-fin ray. Soft dorsal-fin rays 50-60. Anal spines 3 and soft anal-fin rays 50-60; anterior end of dorsal spines posterior to pectoral-fin insertion and anterior end of soft dorsal-fin rays slightly posterior to anterior end of soft anal fin. Pectoral fins small, extended latero-posteriorly, with their bases located mainly below upper margins of gill openings. No pelvic fins. Origin of exposed anal spines slightly posterior to anal. Caudal fin very small and rounded with 7-8 rays, confluent with soft dorsal- and anal-fins. First and second anal spines supported by well-developed first anal spine pterygiophore and third anal spine derived from second spine pterygiophore, situated anteriorly to first soft anal-fin ray. Second anal spine placed close to first spine, but distinctly distant from third spine, much longer than both.
Sinobdella longitubulus is clearly distinguished from the single congeneric species (S. sinensis) by having a more or less white-brown reticulated pattern (vs. many dark brown vertical bars, with very narrow light yellow interspaces) on the flank (Fig.
The epithet name, used here as a noun, is derived from the Latin word longus (= long) and tubulus (= pipe), alluding to two longer tubes modified from anterior nostrils. The common Chinese name here suggested for this new species is “长管华刺鳅”.
Sinobdella longitubulus is currently known from the Meng-Jiang emptying into the Xi-Jiang and the Qingshui-He, a stream tributary to the Hongshui-He discharging into the Xi-Jiang of Zhu-Jiang Basin (Fig.
In formalin-preserved specimens (Fig.
In freshly-、collected specimens (Fig.
A total of 136 COI gene sequences of 1448 bp in length of two Sinobdella species were here amplified. Forty haplotypes (including four outgroups) were detected from the sequences (Suppl. material
Given that Bayesian Inference (BI) and Maximum Likelihood (ML) analyses produced overall identical topologies, only the BI tree with Bayesian posterior probabilities (PP) and bootstrap support (BS) value were provided in Fig.
The genetic distances (p-distances) within and between species were calculated. Intraspecific genetic distance for sampled species of S. sinensis and S. longitubulus were 0.5% and 0.1%, respectively. Interspecific genetic distance between both were 10.5%.
There are seven records of Chinese spiny eels currently housed in MNHN (Table
Catalogued number (No. specimens) |
Location |
Collector |
Collection Time |
MNHN-IC-0000-5021 (one) |
Yangtze River |
C. P. Dabry de Thiersant |
1863 |
MNHN-IC-0000-5022 (one) |
Yangtze River |
C. P. Dabry de Thiersant |
1863 |
MNHN-IC-0000-5230 (two) |
China |
A. David |
1868 |
MNHN-IC-0000-5573 (four) |
China |
A. David |
1868 |
MNHN-IC-0000-7851 (one) |
Mountains of Jiangxi Province |
C. P. Dabry de Thiersant |
1868 |
MNHN-IC-0000-7490 (one) |
China |
A. David |
1870 |
MNHN-IC-0000-7358 (one) |
China |
C. P. Dabry de Thiersant |
1873 |
X-ray photographs of lateral body for Mastacembelus armatus and Sinobdella sinensis. The red frame indicates the differences that exist between the anal spines of the two species.
During 1868 to 1870, A. David made the second trip to central and western China for specimen collection (
Chinese spiny eels under the name of S. sinensis in the BMNH collection are also amongst mastacemblids examined by both
The discovery of this new species from the middle Zhu-Jiang Basin in Guangxi Province necessitates a re-diagnosis of S. sinensis and a delineation of its distribution in China. Characters typical for S. sinensis are given in the diagnosis. According to these characters, this species is extensively known from the mid-lower Chang-Jiang Basin. Populations of river basins north of this river, such as the Huai-He, Hai-He and Luan-He are conspecific with the species, as evidenced by molecular data (Fig.
Except for the count of vertebrae (Table
The number of total vertebrae for S. sinensis from different locations in China.
Basin |
River |
Sampling location |
Specimens examined |
Total vertebrae (mean) |
Middle Zhu-Jiang Basin |
Li-Jiang |
Guiling City and Linchuan County |
n = 2 |
76 (76.0) |
Luoqing-Jiang |
Yongfu County |
n = 14 |
76-77 (76.4) |
|
Middle Chang-Jiang Basin |
Han-Jiang |
Xiangyang City |
n = 11 |
77-80 (78.5) |
She-Shui |
Dawu County |
n = 2 |
80,81(80.5) |
|
Fu-He |
Sui County |
n = 4 |
77,77,80,81 (78.8) |
|
Huan-He |
Xiaochang County |
n = 3 |
76,79,79,81(78.8) |
|
Poyang Lake system |
Gan-jiang |
Wanzai County |
n = 3 |
77,77,79(77.7) |
Gan-Jiang |
Yongxin County |
n = 6 |
77-79(78.0) |
|
Dongting Lake system |
Xiang-Jiang |
Hengdong County |
n = 1 |
78(78.0) |
Xiang-Jiang |
Xing'an County |
n = 4 |
77,78,78,79(78.0) |
|
Yuan-Jiang |
Mayang County |
n = 5 |
76-77(76.8) |
|
Lower Chang-Jiang |
Mainstream |
Susong County |
n = 6 |
78-81(79.8) |
Mainstream |
Tongcheng County |
n = 1 |
80(80.0) |
|
Coastal rivers of southeast China |
Qiantang-Jiang |
Changshan County |
n = 4 |
76,76,76,77(76.3) |
Min-Jiang |
Sanming City |
n = 1 |
77(70.0) |
|
Huai-He Basin |
Huai-He |
Shangcai County |
n = 4 |
77,77,78,79(78.3) |
Huai-He |
Huoshan County |
n = 1 |
77(77.0) |
|
Coastal rivers of north China |
Luan-He |
Luanzhou City |
n = 5 |
76,77,79,80,80(78.4) |
This phenomenon is also observed for S. sinensis in east China. For example, four specimens caught from the Qiantang-Jiang Basin in Changshan County, Zhejiang Province, possessed 76-77 (mean 76.3), fewer than 77-79 (mean 77.8) of nine specimens from the Gan-Jiang (in Poyang Lake system) in Wanzai and Yongxin Counties, Jiangxi Province and 78-81 (mean 79.9) of seven specimens from the lower Chang-Jiang Basin in Susong and Tongcheng Counties and 77-79 (mean 77.6) of five specimens from the Huai-He Basin in Shangcai County of Henan Province and Huoshan County of Anhui Province. It seems that marked variations in the mean number of vertebrae were found between sampling locations north and south of the latitude (30°N). The highest number of vertebrae, though, was not found in the northern-most sampling location in the Luan-He (Luanzhou City). Mean vertebrae count also showed a longitudinally increasing variation from the Qiantang-Jiang to the middle and lower Chang-Jiang Basin. Collectively, the number of vertebrae for S. sinensis varies geographically, probably in association with temperature amongst different regions.
Mastacembelus dienbienensis is a Vietnamese species firstly described by
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Our sincere thanks should be given to Dong-Ming Guo, Xiong Gong, Man Wang and Wei-Han Shao for assisting us in fieldwork and laboratory analysis. We should express our greatest thanks to the Muséum national d'Histoire naturelle (MNHN) and British Museum of Natural History (BMNH) for providing X-ray photographs and information. This research was funded by the special foundation for Natural Science and Technology Basic Research Program of China (2019FY101904), National Science & Technology Fundamental Resources Investigation Program of China (2019FY101800) and the National Nature Sciences Foundation of China (NSFC no.: 31872200).
Peng Shan conceived the study, analysed the data and drafted the writing. Guang-Yu Li gave guidance and E Zhang revised the manuscript. All authors contributed to the writing of the paper.
Detailed information on specimens used in this study. The species with * means the samples available in GenBank.