Oreonectes qinae Chen, Mo, Zhang & Du, 2025

Chen, Zhuo-Ni, Mo, Cai-Huan, Du, Li-Na & Zhang, Li-Na, 2025, Oreonectes qinae (Teleostei, Cypriniformes, Nemacheilidae), a new loach species from Guangxi, China, ZooKeys 1255, pp. 365-377 : 365-377

publication ID	https://doi.org/10.3897/zookeys.1255.158447
publication LSID	lsid:zoobank.org:pub:49729EA9-FB82-4D5A-A519-B06DA5A883C4
DOI	https://doi.org/10.5281/zenodo.17363024
persistent identifier	https://treatment.plazi.org/id/51D6BE3A-2C00-5A45-BA21-1CDF035877D5
treatment provided by	ZooKeys by Pensoft
scientific name	Oreonectes qinae Chen, Mo, Zhang & Du
status	sp. nov.

Treatment

Oreonectes qinae Chen, Mo, Zhang & Du sp. nov.

Tables 1 View Table 1 , 2 View Table 2 , Figs 1 View Figure 1 , 2 View Figure 2 , 3 View Figure 3 , 4 View Figure 4

Type material.

Holotype • KIZ 2024010559 View Materials , holotype, 78.6 mm SL, female; China: Guangxi Zhuang Autonomous Region: Gutingshan Forest Park, Youfeng District, Liuzhou City, Liujiang River , 24.32325°N, 109.51695°E; collected by Z. S. Qin and Y. Cai, December 2024 GoogleMaps . Paratypes • KIZ 2024010560 View Materials –563, four specimens, 46.3–70.5 mm SL, female; KIZ 2024010564 View Materials , 52.1 mm SL, male, data same as holotype GoogleMaps .

Other materials.

• KIZ 2024010565 –571, eight specimens, 30.2–40.0 mm SL, preserved in 99 % ethanol for molecular study, data same as the type specimens GoogleMaps .

Etymology.

The species name, qinae , is in recognition of the contributions of Zi-Shan Qin to the collection of the present specimens and dedicated efforts in fieldwork. We suggest the Chinese vernacular name “ 覃氏岭鳅 ”.

Diagnosis.

This new species can be distinguished from all known species of Oreonectes by a combination of the following characteristics: color pattern present; swim bladder degenerated; black longitudinal stripe from posterior upper pectoral fin to caudal-fin base; dorsal-fin origin posterior to pelvic-fin origin; tip of pelvic fin not reaching anus; caudal fin with irregular black markings; caudal fin rounded; maxillary barbel not reaching posterior margin of opercula; without dark brown V-shaped marking on dorsal surface of head; 16 branched caudal-fin rays; and 12 inner-gill rakers on first gill arch.

Description.

The morphometric and meristic data of Oreonectes qinae sp. nov. are provided in Table 1 View Table 1 . Body elongated and cylindrical (Fig. 1 A View Figure 1 ), slight elevation of head-dorsal junction, deepest body depth 13.2 % – 19.8 % of SL, deepest body depth anterior to dorsal-fin origin, decreasing depth from dorsal-fin origin to caudal-fin base, dorsal-fin origin closer to the posterior margin of the operculum than to caudal-fin base. Head flattened, head width longer than height, head width 60.9 % – 72.6 % of HL, head height 43.5 % – 54.5 % of HL. Whole body covered by scales, except head and thorax. Dorsum of head and above lateral line dark gray. Lighter color below lateral line and abdomen, without body color spots. Mouth inferior, curved, processus dentiformis absent, jaws completely covered by lips (Fig. 1 H View Figure 1 ), snout length shorter than postorbital length of head, visible wrinkles present on surface of lip, lower lip with V-shaped median notch completely interrupted by longitudinal groove (Fig. 1 C View Figure 1 ). Anterior and posterior nostrils closely adjacent, base of anterior nostril tubular, tip elongated to whisker-like, nostril barbel length 90.4 % – 140.2 % of eye diameter.

Three pairs of barbels, well-developed, inner rostral barbel length 30.2 % – 39.1 % of HL, reaching anterior nostril; outer rostral barbel length 47.3 % – 57.3 % of HL, extending to posterior margin of eye; maxillary barbel length 40.8 % – 50.9 % of HL, not reaching posterior margin of opercula. Eyes normal, interorbital width greater than eye diameter, eye diameter 13.0 % – 22.5 % of HL. Tip of pelvic fin close to, but not reaching, anus (Fig. 1 View Figure 1 ). Dorsal-fin origin posterior to pelvic-fin origin. Distance between anus and tip of anal fin 0.9–2.0 times eye diameter. Caudal fin rounded. Caudal-peduncle length greater than width, caudal-peduncle depth 76.0 % – 99.4 % of length, adipose crests along both dorsal and ventral sides absent.

Three unbranched and seven to eight branched dorsal-fin rays, dorsal-fin rays dark, membrane transparent and scattered with black pigments, two unbranched and nine to 10 branched pectoral-fin rays, two unbranched and six to seven branched pelvic-fin rays, three unbranched and five branched anal-fin rays, 16 branched caudal-fin rays. Inner-gill rakers on first gill arch 12 (2). Cephalic lateral-line system well-developed, 9–10 + 4 infraorbital pores, 7–8 supraorbital canal pores, six supratemporal canal pores, 9–10 preoperculo-mandibular canal pores. Lateral line incomplete, with 11–13 lateral-line pores, last lateral-line pore not reaching tip of pectoral fin.

Posterior chamber of swim bladder degenerated, only 1.5 times eye diameter (Fig. 2 A View Figure 2 ). Stomach U-shaped, intestine curved along stomach, leading directly to anus (Fig. 2 B View Figure 2 ).

Genetic comparisons.

BI analysis based on 1116 bp of Cytb sequences produced consistent topologies. The phylogenetic reconstruction confirmed the validity of the new species, with high nodal support (BPP ≥ 0.95). All Oreonectes species formed a well-supported monophyletic group, phylogenetically resolved as the sister lineage to the clade containing Guinemachilus and Micronemacheilus . Oreonectes qinae sp. nov. formed a highly supported clade with O. damingshanensis and O. zhangi (Fig. 3 View Figure 3 ). Uncorrected p - distances based on Cytb between Oreonectes qinae sp. nov. and the nine other species ranged from 1.4 % ( O. damingshanensis ) to 8.7 % ( O. guananensis ) (Table 2 View Table 2 ).

Sexual dimorphism.

Mature males with genital papilla positioned immediately posterior to anus; gonopore opening at tip of fleshy prominence (Fig. 1 G View Figure 1 ); feature absent in females (Fig. 1 C View Figure 1 ). Females generally larger than males, with pelvic-fin length measuring 17.33 % of SL in female KIZ 2024010559 vs. 16.9 % in male KIZ 2024010564 .

Coloration.

Dorsum of head and above lateral line dark gray. Lighter color below lateral line and abdomen, without body color spots. In both sexes, distinct black stripe extending from lateral line to caudal-fin base; caudal-fin base black. In life, body dark gray except abdomen pinkish; small black spots covering body except on abdomen; no irregular spots (Fig. 1 D View Figure 1 ). Dorsal fin with black pigments on fin membrane. In formalin-fixed specimens, body color, black spots, and stripe somewhat faded, dark gray above head and lateral line, light color below lateral line, abdomen white (Fig. 1 A – C, E – G View Figure 1 ).

Distribution and habitat.

Oreonectes qinae sp. nov. is currently only known from Gutingshan Forest Park, Youfeng District, Liuzhou City, Guangxi Zhuang Autonomous Region, China, in the Liujiang River drainage ( 24.32325°N, 109.51695°E) (Fig. 4 A View Figure 4 ). The species inhabits small streamlets with water depths ranging from 0.5 to 1.5 m, characterized by rocky substrate and abundant macrophyte growth, providing suitable habitat conditions (Fig. 4 B View Figure 4 ). Other aquatic species observed in the same streamlet include the crab Qianguimon splendidum Huang, 2018 , and the shrimp Caridina huananensis Liang, 2004 ; there is no other fish in the habitat.