Triplophysa wulongensis, Chen & Sheraliev & Shu & Peng, 2021

Chen, Shijing, Sheraliev, Bakhtiyor, Shu, Lu & Peng, Zuogang, 2021, Triplophysa wulongensis, a new species of cave-dwelling loach (Teleostei, Nemacheilidae) from Chongqing, Southwest China, ZooKeys 1026, pp. 179-192 : 179

Triplophysa wulongensis sp. nov. Figures 1 , 2 ; Table 3

Type material.

Holotype. SWU2019051309, male, 64.0 mm SL. P. R. China: Chongqing City; Wulong County: subterranean pool in Furong Cave (29°24'1.09"N, 107°54'11.60"E); collected by Ni Liu, May 2019 .

Paratypes. SWU2019051301-2019051308, 8 ex., 49.0- 67.2 mm SL; collected with the holotype.

Diagnosis.

Triplophysa wulongensis can be distinguished from its congeners by the following combination of characters: eyes present (vs absent in T. anshuiensis , T. erythraea , T. huanjiangensis Yang, Wu & Lan, 2011, T. rosa Chen & Yang, 2005, T. xiangxiensis and T. posterodorsalus ); anterior nostril barbel-like (vs anterior nostril not elongate to barbel-like in T. erythraea , T. flavicorpus , T. huapingensis Zheng, Yang & Chen, 2012 and T. tianxingensis ): caudal fin with 18 branched rays (vs 14-16 in T. guizhouensis , T. lingyunensis (Liao, Wang & Luo, 1997), T. nandanensis , T. shilinensis and T. zhenfengensis Wang & Li, 2001), vertebrae 4+38-39 (vs 36-37 in T. nasobarbatula Wang & Li, 2001 and T. sanduensis ; 42-43 in T. siluroides ); predorsal length 50.4-54.2% of standard length (vs 46.1-48.0% in T. sanduensis ); posterior chamber of gas bladder degenerate (vs developed in T. anshuiensis , T. tianxingensis and T. xichouensis ); body smooth and scaleless (vs body covered by scales in T. longipectoralis Zheng, Du, Chen & Yang, 2009 and T. yunnanensis ); lateral line complete (vs incomplete in T. huanjiangensis ); and pelvic-fin tip not reaching to anus (vs reaching to anus in T. gejiuensis , T. macrocephala Yang, Wu & Yang, 2012, T. rosa and T. qiubeiensis ).

Description.

Morphometric data of the type specimens of T. wulongensis are presented in Table 3 . D, 2/8-9; A, 1/5-6; P, 1/8-9; V, 1/5-7; C, 18; vertebrae: 4+38-39 (five specimens).

Body elongated, slightly compressed anteriorly and more strongly compressed posteriorly. Deepest point of body in front of dorsal fin origin, body depth 9.3-13.6% of SL. Caudal peduncle depth/caudal peduncle length range from 44.3% to 57.4%. Head depressed, width greater than depth (62.4% vs 50.6% of HL). Snout moderately blunt and snout length almost equal to postorbital length, approximately 38.9-45.0% of HL. Anterior and posterior nostrils adjacently located; anterior nostril in short tube, each with tip elongated to form a short barbel. Tip of nostril appendage not reaching the anterior margin of eyes. Eyes present, diameter 11.1-19.1% of HL. Mouth inferior, arched; mouth corner situated below anterior nostril. Lips thin; lower lip with well-marked, V-shaped, median notch (Fig. 2 ). Upper jaw covered by upper lip; lower jaw scoop-shaped, not covered medially by lower lip. Three pairs of barbels; inner rostral barbel extending to rictus, 16.5-23.4% of HL; outer rostral barbel not extending to anterior margin of eyes, 21.4-41.5% of HL; maxillary barbel extending to anterior margin of eyes, 21.8-35.9% of HL.

Dorsal fin emarginate, origin posterior to pelvic fin insertion, situated slightly posterior to midpoint between snout tip and caudal fin base; first branched ray longest; dorsal fin height shorter than lateral head length; tip of dorsal fin reaching vertical of anus. Pectoral fin moderately developed, 56.6-72.9% of distance between pectoral fin and pelvic-fin origins. Pelvic-fin origin situated almost at midpoint between pectoral-fin origin and anal-fin origin, tip of pelvic fin not reaching to anus. Anal-fin origin situated almost at midpoint between pelvic-fin origin and caudal-fin base, distal margin of anal fin truncate; posterior tip of anal fin reaching approximately half distance between anal-fin origin and caudal-fin base. Vent-anal fin-origin distance 4.0-7.2% of SL. Caudal fin emarginate.

Body smooth and scaleless. Cephalic lateral line system developed. Lateral line complete, ending at caudal-fin base. Intestine without bends or loops immediately posterior to stomach; stomach U-shaped. Posterior chamber of gas bladder degenerate.

Coloration.

In formalin-fixed specimens, body yellowish dorsally, gradually lighter toward ventral side. Fins semitransparent. Body dorsally and laterally covered with irregular, brown blotches; 6-8 distinct dark brown blotches along dorsal midline.

Sexual dimorphism.

Sexual dimorphism was not detected. This may reflect that the sampling time was outside the breeding season of this species.

Geographical distribution.

Known only from the type series, from a pool in Furong Cave, connected to the Wujiang River near Wulong, (Fig. 3 ). Triplophysa wulongensis was found syntopic with T. rosa .

Etymology.

The specific name, Triplophysa wulongensis , refers to the type locality in Wulong County, where the type specimens were collected; it is an adjective with alternative endings - is and - e.

Figures

Figure 1. Triplophysa wulongensis sp. nov., holotype, SWU 2019051309, 64.0 mm SL A lateral view B dorsal view C ventral view.

Figure 2. Triplophysa wulongensis sp. nov., holotype SWU 2019051309, 64.0 mm SL; head in dorsal and ventral view.

Figure 3. Collection site of Triplophysa wulongensis sp. nov. (red triangle) in Chongqing, Southwest China.