Corresponding author: Tian-Xiang Gao (
Academic editor: M.E. Bichuette
A new
Xiao J-G, Yu Z-S, Song N, Gao T-X (2021) Description of a new species,
The family
Reliance only on morphology to identify fishes to the species level is challenging when the diagnostic characters are similar among related taxa. Species of the family
The most important character commonly used to identify
While undertaking a taxonomic review of the genus
The unidentified specimens were collected from the southern coast of China, more precisely in Fuding (Fujian, 50 individuals), Xiamen (Fujian, 40 individuals), Changhua (Taiwan, 1 individuals), Chiayi (Taiwan, 17 tissues), Shantou (Guangdong, 6 individuals), Zhuhai (Guangdong, 18 individuals), Zhanjiang (Guangdong, 30 individuals), Beihai (Guangxi, 80 individuals), Fangchenggang (Guangxi, 50 individuals), Haikou (Hainan, 4 individuals), and Danzhou (Hainan, 6 individuals) (Fig.
Sampling sites and corresponding sample sizes (represented by circle size and Arabic numerals) of
In this study, the recorded ten
Comparison of
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X–XII, I, 20–22 | XI, I, 21–22 | XI, I, 22 | X–XII, I, 20–22 | XI, I, 20–22 | XII–XIII, I, 20–22 | XI, I, 20–23 | XI, I, 22–23 | X–XI, I, 20–22 | X–XII, I, 19–22 | X–XI, I, 20–22 |
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II, 20–22 | II, 21–22 | II, 23 | II, 18–23 | II, 21–22 | II, 22–24 | II, 21–23 | II, 23–24 | II, 21–23 | II, 18–22 | II, 21–23 |
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67–75 | 67–70 | 70 | 69–84 | 70–73 | 79–84 | 68–72 | 71 | 75–79 | 63–74 | 68–71 |
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4–6/9–12 | 6–7/8–9 | 5/10–11 | 4–5/7–10 | 5–6/10–12 | 7/11–12 | 5–6/10–12 | 5/11 | 5–6/9–11 | – | 5–6/10–12 |
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2–4/5–8 | – | – | 3–4/7–8 | 3–4/5–6 | 1–2/7–9 | 3/8–9 | 4/11 | 2–4/6–8 | 3–4/8–10 | 3–4/7–8 |
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34–35 | 34 | – | 34 | 35 | 39–40 | 34 | 35–36 | 37–39 | 34 | 33–35 |
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25.1–30.8 | 30.0–31.0 | 33.0 | 27.9–35.0 | 26.1–31.0 | 25.9–27.7 | 24.0–30.0 | 29.0–30.1 | 24.7–29.8 | 26.6–27.0 | 27.5–32.4 |
The genus and species classification followed
All measurements were made with dial calipers and dividers to the nearest 0.1 mm. The definition of the modified vertebrae followed
To analyze genetic differences between this new species and other congeners, mitochondrial (
Forty specimens of eight
Net genetic distances (
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0.000±0.000 | |||||||
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0.193±0.021 | 0.000±0.000 | ||||||
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0.084±0.012 | 0.202±0.022 | 0.002±0.001 | |||||
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0.211±0.023 | 0.168±0.019 | 0.214±0.023 | 0.001±0.001 | ||||
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0.177±0.020 | 0.210±0.022 | 0.172±0.020 | 0.211±0.023 | 0.001±0.001 | |||
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0.213±0.023 | 0.152±0.017 | 0.224±0.023 | 0.124±0.015 | 0.196±0.021 | 0.003±0.002 | ||
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0.192±0.020 | 0.214±0.022 | 0.206±0.022 | 0.217±0.022 | 0.210±0.022 | 0.222±0.023 | 0.004±0.002 | |
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0.204±0.022 | 0.194±0.021 | 0.216±0.022 | 0.192±0.021 | 0.181±0.019 | 0.196±0.021 | 0.198±0.021 | 0.001±0.001 |
The specific name
Relatively large body and usually with a wide mid-lateral black stripe from opercular to caudal peduncle; dorsal-fin rays X–XII (mostly XI), I+20–22, soft anal fin rays 20–22; scales in lateral line 67–75, scales above lateral line 4–6; gill rakers 2–4+5–8; vertebra: abdominal 14 or 15 (mostly 14), modified 3–7 (mostly 4 or 5), caudal 13–18, and total 34 or 35 (mostly 34) (Table
Morphometric measurements for type specimens of
Morphometric measurements (mm) and counts | Holotype | Paratypes (n = 107) |
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37.0 | 16.2–49.3 |
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174.5 | 140.4–187.8 |
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151.2 | 121.0–163.0 |
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45.3 | 33.7–46.5 |
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18.9 | 15.0–22.3 |
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8.1 | 6.8–11.6 |
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10.7 | 6.0–14.1 |
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17.0 | 12.9–19.1 |
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24.3 | 17.4–27.2 |
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19.3 | 17.0–22.4 |
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16.2 | 10.8–20.0 |
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9.9 | 7.1–11.1 |
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36.7 | 25.3–40.0 |
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52.6 | 41.1–64.8 |
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54.2 | 42.8–58.2 |
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24.2 | 18.2–27.1 |
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23.1 | 17.4–27.2 |
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XI, I+21 | X–XII, I+20–22 |
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16 | 14–16 |
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I+5 | I+5 |
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II+22 | II+20–22 |
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17 | 16–18 |
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3+7 | 2–4+5–8 |
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34 | 34–35 |
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69 | 67–75 |
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6/11 | 4–6/9–12 |
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16.1 | 13.4–17.4 |
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29.9 | 25.1–30.8 |
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10.7 | 7.9–13.4 |
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17.9 | 16.5–24.9 |
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23.5 | 14.8–31.2 |
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41.7 | 39.6–52.7 |
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37.6 | 33.2–42.4 |
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61.0 | 51.3–88.5 |
General body features are shown in Figure
Swim bladders of nine
Neighbor-joining (
Body covered with small or moderate sized ctenoid scales, and cheek scales cycloid, arranged in two or three rows. Lower part of pre-opercular-mandibular canal covered with cycloid scales. The base of pectoral fin and ventral fin lacking scales. Lateral line beginning above gill aperture and anterior portion of pectoral fin, extending along curve of dorsal edge to the end of body.
Two separated dorsal fins, first dorsal fin XI (X–XII), obviously higher than second, origin posterior to top of pectoral fin base, composed of spines, gradually shortening. Fin membrane with dense black spots. Base of second dorsal fin long, composed of a single spine and 21 (20–22) soft rays, originating mid-body, and not extending to caudal fin origin when placed flat. Origins of anal fin slightly posterior to cloacal pore, with II+22 (20–22), not extending to caudal fin origin when placed flat. Pectoral fin 16 (14–16), slender. Two separated ventral fins broad, I+5, approximately triangular, and shorter than pectoral fin.
Upper surface of head dark brown and trunk bright brown, grading to silver on abdomen. Dorsal side of snout brownish gray. Cheek yellow, slightly silver posteriorly, with black dots amassed on the anterior inferior part of eyes. A wide faint stripe composed of tiny black dots on skin always present, from opercular to caudal peduncle. Dorsal fins yellowish hyaline, small dark dense spots on fin membrane. Pectoral, ventral, and anal fins yellowish hyaline with dark spots; caudal fin yellowish dusky with a black margin and grayish brown margin posteriorly, lobes usually broadly truncated posteriorly.
Swim bladder large. Two anterior extensions diverging to terminate on either side of the basioccipital above the auditory capsule. Two posterior tapering extensions of the swim bladder penetrating into the caudal region, one usually longer than the other. Two anterolateral extensions originate anteriorly, each branch into anterior and posterior sub-extensions: the anterior one comprising a short, simple blind tubule and the posterior sub-extensions kinked, long and complex, extending along the abdominal wall ventral to the base of the posterior extensions, respectively, tangent but not interconnected. A single duct-like process originating from ventral surface of swim bladder extending to the urogenital opening and a sub-extension connecting with a sanguineous vesicle close to vertebra, of unknown function. Eight or nine lateral processes extending from entire lateral surface of main body of swim bladder, anterior three or four stout and horn-like, posterior five or six small and triangular in shape.
Habitat is similar to
According to the subgeneric grading system in
Moreover, by the primary diagnostic features (Table
As for the shape of swim bladder (Fig.
Species-level taxonomy for
According to the conventional classification of
At present, the distribution of
We deeply thank Shih-Chieh Shen, Jin-Chywan Gwo, Yuan Li, Bin-Bin Shan, Xiong-Bo He, Jian-Wei Zou, Dong-Ping Ji and Qiang Xu for sample collection. We are also grateful to Ms. Nan Zhang for her valuable suggestions for the manuscript. This work is supported by National Natural Science Foundation of China (Nos. 41776171, 41976083). All authors declare that they have no conflict of interest.