Beaufortia viridis Chen & Li & Tang & Pu & Lei 2024, sp. nov.
Creators: name: Chen, Jing-Chen
name: Li, Jia-Jia
name: Tang, Wen-Qiao
name: Pu, Xin-Rui
name: Lei, Hao-Tian
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Cypriniformes
Balitoridae
Beaufortia
Beaufortia viridis

description: Beaufortia viridis Chen & Tang sp. nov.
Figs 10, 11, 12
Beaufortia pingi: Yue (1981): 170–172, Lingyun County, Guangxi, admixed within B. pingi. Zheng (1989): 257 –258, Lingyun County, Guangxi, admixed within B. pingi.
Beaufortia pingi: Chen (1990): 85–87, Xiyang River, Guangnan County, Yunnan.
Beaufortia zebroidus: Chen and Tang (2000): 504–505, Tian′e County, Guangxi. Chen (2013): 292, Xiyang River, Yunnan.
Type material.
Holotype. SHOU 20240103101, 48.42 mm total length (TL), 38.03 mm standard length (SL), adult (Fig. 10). Collected by Jing-Chen Chen and Qian-Yu Liang on 27 December 2023, from Wuming River, a stream tributary to the You River of the Pearl River basin, at Wuming District, Nanning City, Guangxi Province, China (24 ° 20.34 ' N, 106 ° 21.624 ' E; c. 160 m a. s. l.) (Fig. 13).
Paratypes. 15 specimens from the same locality as holotype, SHOU 20240103102-116, 18.82–46.64 mm SL, were collected by Qian-Yu Liang and Jing-Chen Chen on 27 December 2023; eight specimens from Lingyun County, Baise City, Guangxi Province, China, SHOU 20240126101-108, 50–59.85 mm SL, were collected by Qian-Yu Liang and Jing-Chen Chen on 24 January 2024; five specimens from Guangnan County, Wenshan Zhuang, and Miao Autonomous Prefecture, Yunnan Province, China, SHOU 20240109101-105, 36.23–54.20 mm SL, were collected by Lao Xing on 28 December 2023.
Additional materials.
Seven specimens from Guangnan County, Wenshan Zhuang, and Miao Autonomous Prefecture, Yunnan Province, China, SHOU 20240112101-107, 39.97–48.64 mm SL, were collected by Lin Yang and Lao Xing from December 2022 to February 2023.
Diagnosis.
B. viridis sp. nov. shares the typical characteristics with members of the B. pingi species group, with distinct vertical stripes on lateral body and a pinnate-type lower lip (vs. lacking prominent vertical stripes and having a dicot-type lower lip in other congeneric species apart from this group) (see Figs 6 C, 7, Table 2). B. viridis sp. nov. can be clearly distinguished from B. granulopinna, B. pingi, and B. zebroida by consistent vertical stripes with uniform length, width, and inter-spacing at all growth stages (stripes on mid-section lateral body occasionally shorten in individuals from the Xiayang and Tuoniang Rivers in Yunnan) (vs. a certain proportion (54.76 %) of adults exhibit blurred or vanished vertical stripes on mid-section lateral body in B. granulopinna; stripe length and width uneven, with a high proportion (94.00 %) of adults showing blurred or vanished mid-section vertical stripes in B. pingi; stripe length and width uneven, typically narrower than inter-spacing, sometimes reduced to dots in B. zebroida). B. viridis sp. nov. can be further distinguished from B. granulopinna sp. nov. by the lack of prominent tubercles on the branched rays of the pectoral fins (vs. well-developed tubercles on anterior 6–9 rays of the pectoral fins present). Moreover, B. viridis sp. nov. differs from B. zebroida by body dark cyan to green in dorsal profile (vs. brown yellow to golden).
Description.
Dorsal iii- 7, anal ii- 4, pectoral i- 19–23 (21.08 ± 1.02), pelvic i- 14.5–19 (17.11 ± 1.01). Lateral-line canal pores and scales: 65–83 (73.47 ± 4.21) (see Table 2).
Morphometric measurements for the specimens examined are given in Table 3. See Fig. 10 for lateral, dorsal, and ventral views of the body.
Head-thorax cylindrical, dorsal slightly humped medially, flattened ventrally, body compressed from pelvic fins to caudal peduncle. Head broad, blunt, length slightly less than width, more than depth, nuptial tubercles well-developed on lower half of head in mature individuals, snout rounded, length about half of head length. Mouth inferior, narrow, width about one-fifth head width, horseshoe-shaped, angle about 94 ° from midpoint to ends. Upper lip smooth, without distinct papillae; lower lip pinnate-type, slightly concave medially with multilobed sides; jaw edges slightly protrude. Shallow groove between upper lip and snout, extending to mouth corners. Lateral grooves shallow or indistinct. Two pairs of rostral barbels present, with outer pair slightly longer, space between rostral barbels with leaf-like folds, edges of which rounded and poor developed. One pair of maxillary barbels, length about equal to outer rostral barbels. Nostrils with tubular nasal flaps, distance between nostrils equals one-third head width. Eyes supralateral, medium-sized, eye diameter about one-quarter head length, interorbital space flat, width about half head width. Gill opening small, about equal to eye diameter, originated about vertically above the second to third branched pectoral fin ray, limited to dorsal side of head. Scales small, diameter smaller than pupil, dorsal surface of head, base of paired fins, and ventral area before pelvic fin bases nude. Lateral line complete, at midlateral.
Dorsal fin base about equal to pre-pectoral length, starting around midpoint from snout to caudal fin base, adpressed extending to about midway between dorsal fin origin and caudal fin base. Anal fin base length about half of that of dorsal fin base, adpressed extending to slightly beyond caudal fin base. Paired fins extending outwards, forming disc-like structure with body. Pectoral fin base slightly longer than head length, starting at the posterior one-third point of head, pectoral fin length about twice to head length, tip of which reaching pelvic fin base midpoint, pectoral disc width about 1.5 times head width at pectoral origin, tubercles on rays absent. Pelvic fin shorter than pectoral, with well-developed fleshy flap at dorsal base, last 1–3 branched rays partially connected by fin membrane forming pelvic disc, connected part about two-thirds ray length, remaining parts separated, forming notch in middle rear edge, exposing anus. Pelvic disc width about equal to length. Anus at or near posterior edge of pelvic disc, distance to which less than to anal fin origin. Caudal fin length about equal to pelvic fin, slanted end, lower lobe slightly longer.
Coloration in preservation.
Preserved specimen from sub-adult to adult stage, body dark green to grey, white ventrally. Head with black spots or vermiculation dorsally, 2–5 larger black blotches along mid-dorsal body anterior to dorsal fin. Sides with 9–15 thick dark vertical stripes, with uniform length, width, and inter-spacing, easily recognizable at all ages. Paired fin with pale-white or hyaline margin, inner edges with continuous or dotted black arc. Dorsal fin hyaline with black stripes, one black spot present on the root before the second branched ray.
Coloration in live.
In life, sides of body dark cyan to green. After maturity, black stripes and spots on body turn metallic green, inter-spacing and hyaline fin membranes pale yellow.
Juvenile morphology.
Pelvic fins completely separated, body dark green in dorsal profile, few wider vertical dark stripes on sides, 2–3 vertical black stripes on caudal fin, other fins hyaline or with inconspicuous black lines (see Fig. 11).
Sexual dimorphism.
In fully mature individuals, males generally slightly larger than females, with well-developed tubercles (see Fig. 8 A, B).
Geographic variation.
From east to west, vertical stripes generally tend to become thinner. Specimens from type locality, inter-spacings narrower than dark stripes, sometimes appearing fissure-like (see Fig. 10). In contrast, Lingyun County populations typically exhibit broader and taller bodies, shorter and thicker caudal peduncles, longer snouts, and wider inter-spacings (see Fig. 12 A, Table 4). In populations from the Xiyang River and Tuoniang River, vertical stripes vary greatly, sometimes becoming finer, inter-spacings wider than stripes, few individuals with shorter stripes before caudal peduncle (see Fig. 12 B).
“ * ” indicates that, in a one-way ANOVA test, post-hoc comparisons show significant differences in the trait in question from populations in other regions (p <0.05). “ ** ” indicates that, in an independent sample T-test, the trait in question significantly differs from populations in other regions (p <0.01).
Individual variation.
Two specimens, SHOU 20240109101 and SHOU 20240112102, from Tuoniang River, Guangnan County, Yunnan, vertical stripes notably shortened. One specimen, SHOU 20240109701, from Chengbi River, Lingyun County, Guangxi, possesses completely separated pelvic fins.
Ethology.
Inhabits shallow streams with rapid currents and smooth pebble substrates that adhere to crevices between stones. Feeds on algae and small invertebrates and consumes mucus from fresh fish carcasses. Exhibits territorial behavior.
Distribution.
Found exclusively in small tributaries from the Tuoniang River, Xiyang River, Leli River, and Wuming River to the You River basin, the upper reaches of the Pearl River system, central Guangxi, and eastern Yunnan, China (see Fig. 9).
Etymology.
Species epithet “ viridis, ” from Latin, meaning “ green, ” describes bright green coloration over dorsal body after sexual maturity, in nominative masculine. We propose the Chinese common specific name “ 绿斑爬岩鳅. ”
description: Published as part of Chen, Jing-Chen, Li, Jia-Jia, Tang, Wen-Qiao, Pu, Xin-Rui & Lei, Hao-Tian, 2024, Taxonomic resolution of the hillstream suck-loach Beaufortia pingi species group (Cypriniformes, Gastromyzontidae) and two new species from Southwest China – Beaufortia granulopinna and Beaufortia viridis, pp. 941-963 in Zoosystematics and Evolution 100 (3) on pages 941-963, DOI: 10.3897/zse.100.124370