Bibarba parvoculus, Wu, Tie-Jun, Yang, Jian & Xiu, Li-Hui, 2015

Wu, Tie-Jun, Yang, Jian & Xiu, Li-Hui, 2015, A new species of Bibarba (Teleostei: Cypriniformes: Cobitidae) from Guangxi, China, Zootaxa 3905 (1), pp. 138-144: 139-143

publication ID

http://dx.doi.org/10.11646/zootaxa.3905.1.9

publication LSID

lsid:zoobank.org:pub:35B51518-5366-444A-803A-F4648B48511E

persistent identifier

http://treatment.plazi.org/id/B36387EC-FFE8-B376-8481-FE23FA8BF815

treatment provided by

Plazi

scientific name

Bibarba parvoculus
status

sp. nov.

Bibarba parvoculus  sp. nov.

( Figs. 1View FIGURE 1, 5View FIGURE 5)

Type material. Holotype: GAFS 10110586, male, 51.7 mm SL, collected from a karst cave (24 ° 47 ′ 55.65 ″ N, 108 ° 44 ′ 40.27 ″ E, alt 232 m) in Jicheng village, Tianhe Town, Luocheng County, Guangxi Zhuang Autonomous Region, China by Lan Jiahu on 12 Nov. 2010.

Paratypes: GAFS 10110583, one female, 57.3 mm SL; GAFS 0 8090070, GTEU 10110584 –10110585, 3 females, 52.5–57.3 mm SL. All data same as sample of holotype except GIF 0 8090070 was collected on 20 Sep. 2008.

Diagnosis. Bibarba parvoculus  can be distinguished from its only congener B. bibarba  by having 13–14 branched caudal fin rays (vs. 16); no longitudinal lines of spots on the side of body or any pigment in fins (vs. five longitudinal lines of dark speckles on the sides of body; two or three striations on the dorsal fin and five or six on caudal fin); tip of snout with a semi-transparent fleshy process (vs. snout normal); origin of anal fin nearer insertion of pelvic fin than to caudal fin base (vs. anal fin located half the distance between pelvic and caudal fins); preanal distance 70.4–72.2 % SL (vs. 76.9–83.3); eyes smaller (eye diameter 3.7–12.7 % HL vs. 14.1–20.8); caudal peduncle slender (caudal peduncle depth 36.5–43.4 % SL vs. 43.5–62.5; caudal peduncle length 19.9–22.2 % SL vs. 14.1–19.6) and shorter barbels (rostral barbel length 6.7–8.2 % HL vs. 8.6–15.6; maxillo-mandibular barbel length 8.3–9.7 % HL vs. 10.6–16.3).

Description. Morphometric characters are given in Table 1. Dorsal-fin rays iii, 7 (4) or 8 (1); pectoral-fin rays i, 8 (5); pelvic-fin rays i, 6 (5); anal-fin rays 5 (3) or 6 (2); branched caudal-fin rays 13 (1) or 14 (4).

*data are from Chen & Chen (2007).

Body small, elongate, and laterally compressed. Dorsal profile of head slightly convex; ventral profile of body straight. Head small, laterally compressed. Snout rounded, with a semi-transparent fleshy pad on its tip. Nostrils close together, nearer to anterior edge of eye than to snout; anterior nares in short tube. Eyes presented on upper part at middle of head, and covered by fat; some specimens, eyes vestigial, remaining as black spots; interorbital width greater than eye diameter. Suborbital spine present, located anterior to orbit; spine bifid and with a mediolateral process ( Fig. 2View FIGURE 2). Mouth small, inferior, and arched, with a triangle opening. Lips fleshy; upper lip arched and connected with lower lip; lower lip developed with a longitudinal mental groove at the middle of lower lip, each side of lower lip with a developed fleshy mental lobe ( Fig. 3View FIGURE 3). Two pairs of small barbels; rostral barbels shorter than maxillo-mandibular barbels; maxillo-mandibular barbels with tiny papillae, and connected with lower lip; tip of maxillo-mandibular barbels not reaching anterior edge of orbit.

Bibarba parvoculus  B. bibarba  *

Holotype Paratypes Mean Catalogue number GAFS GAFS GAFS GTEU GTEU

10110586 10110583 0 8090070 10110585 10110584

Dorsal fin origin nearer tip of snout than to caudal fin base; dorsal fin length shorter than head length; profile of dorsal fin truncate. Pectoral fin of male 22.2 % SL ( GAFS 10110586); in females, pectoral fin smaller, 13.4–15.2 % SL (4 specimens; mean= 14.1, SD= 0.8). Pelvic fin short, its origin opposites dorsal fin origin; depressed pelvic fin not reaching anus. Anus situated anterior to anal fin. Anal fin small, its origin nearer to pelvicfin origin than to caudal fin base. Caudal peduncle long, with dorsal and ventral crests. Caudal fin emarginate, tips slightly arched.

Head without scales. Body scales small, oval, and embedded under epidermis. Lateral line not observed. Intestine very simple and straight without loops.

Males smaller than females with proportionally longer pectoral fin. First branched pectoral-fin ray of male thickened and elongated, and longest ray of fin; second branched pectoral fin ray with semicircular lamina circularis ( Fig. 4View FIGURE 4). First branched pectoral-fin ray of females as long as the second branched ray; pectoral fin without lamina circularis.

Coloration. Live coloration of Bibarba parvoculus  is provided in Figure 5View FIGURE 5. Body whitish, and semitransparent; black pigment irregularly present on dorsum of body; black stripe extending from insertion of rostral barbel to orbit; interrupted black stripe extending from orbit to operculum. Two dark spots present on upper and lower of caudal fin base; fins transparent, without pigment. After fixed in 10 % formalin, body whitish, base of pectoral-fin origin, base of dorsal-fin origin, base of anal-fin, and dorsal and ventral crests on caudal peduncle yellowish; pigments on body same as living status.

Distribution. At present, Bibarba parvoculus  is only known from a karst cave (24 ° 47 ′ 55.65 ″ N, 108 ° 44 ′ 40.27 ″ E, alt 232 m) in Jicheng village, Tianhe Town, Luocheng County, Guangxi Zhuang Autonomous Region, China.

Habitat and ecology. An underground stream was found 30 m after entering the cave and about 12 m beneath the surface of the cave entrance. Bibarba parvoculus  inhabits the pools with mud and cobblestone beds ( Fig. 6View FIGURE 6). The areas of pools are 5–50 m 2, with 1–3 m depth. Different pools are connected by holes under water. Bibarba parvoculus  was syntopic with Oreonectes microphthalmus Du et al. 2008  , Sinocyclocheilus brevis Lan & Chen 1992  and Pterocryptis anomala (Herre, 1933)  .

Etymology. The specific name parvoculus  is Latin for “with small eyes”. Parv deriving from parvus, meaning small; oculus means eye. Parvoculus  refers to the smaller eyes when compared with Bibarba bibarba  .

TABLE 1. Morphometric characters of B. parvoculus and B. bibarba.

Standard length (mm) 51.7 57.3 56.7 56.7 52.5  
  10.3 10.5 10.0 11.0 10.7  
GAFS

Ganzhou Forestry School