Acrossocheilus kreyenbergii ( Regan, 1908 )

Yuan, Le - Yang & Zhang, E, 2010, Type locality and identity of Acrossocheilus kreyenbergii (Regan, 1908), a senior synonym of Acrossocheilus cinctus (Lin, 1931) (Teleostei: Cyprinidae), Zootaxa 2684, pp. 36-44 : 37-40

Acrossocheilus kreyenbergii ( Regan, 1908)

( Fig. 2 A–E; Fig. 3 A–B)

Gymnostoma kreyenbergii Regan, 1908: 109 (Nankancho, near Tinghsiang = presently Pingxiang City of Jiangxi Province); Kreyenberg & Pappenheim, 1908: 97 (Yangtze River).

Barbus hemispinus cinctus Lin, 1931: 124 (Yaoshan, Kwangsi) .

Lissiocheilus hemispinus: Lin, 1933: 213 (Yaoshan, Kuangxi) ; Wu,1939: 101 (Yangshuo, Guangxi).

Acrossocheilus (Lissochilichthys) hemispinus cinctus: Wu et al., 1977: 278 (Yangshuo and Guilin, Guangxi).

Acrossocheilus hemispinus: Fang, 1981: 75 (Xing’an, Guilin, Yangshuo, Lipu, Pingle, Zhaoping, Longsheng, Xiangzhou, Longzhou, Wuzhou, and Bobai, Guangxi); Lin, 1989: 180 (Guilin, Guangxi); Chen et al., 1991: 146 (Zhaoqing, Guangdong).

Acrossocheilus hemispinus hemispinus: Zhang, Liu & He, 1996 : (northeastern Jiangxi Province)

Acrossocheilus hemispinus cinctus: Shan et al., 2000: 102 (Yangshuo and Guilin, Guangxi).

Diagnosis. A barred species of Acrossocheilus with six vertical black bars, each two scales in width, on the flank. The vertical bars are more indistinct in adult males than in females, absent in some larger individuals. Acrossocheilus kreyenbergii shares with A. fasciatus (Steindachner) , A. jishouensis Zhao, Chen & Li , A. parallens (Nichols) and A. wenchowensis Wang the presence of the second primary vertical black bar positioned posterior to the base of the last simple dorsal-fin ray and a longitudinal black stripe extending along the lateral line on the flank of adults. This species is similar to A. jishouensis and A. parallens , with which it shares the possession of vertical bars not extending beyond the lateral line on the flank, but differs from them in having a stout (vs. slender) last simple dorsal-fin ray. It is further separated from A. jishouensis by having small serrations along the posterior edge of the last simple dorsal-fin ray (vs. absent) and from A. parallens by having oblong, black blotches on the membranes between the dorsal-fin rays (vs. absent).

Description. Morphometric data are provided in Table 1; refer to Figures 2 and 3 for general body appearance. Body elongate, compressed; greatest body depth immediately anterior to dorsalfin origin; least depth of caudal peduncle closer to caudal-fin base than to posterior end of anal-fin base. Dorsal profile convex; ventral profile round. Head moderately small; interorbital space wide, somewhat convex. Eye moderately large, dorsolaterally positioned. Snout blunt, protruding, with a shallow lateral groove extending along anteroventral margin of lachrymal, confluent with postlabial groove. Mouth subterminal, deeply arched. Gape greater than one-thirds of head width. Upper jaw extending posteriorly to vertical below nostril. Rostral fold present, overlying base of upper lip. Upper lip fleshy, fully adnate to upper jaw, continuous with lower lip around corners of mouth. Lower lip well-developed, completely bisected longitudinally by a shallow groove at dentary symphysis into two lateral lobes, separated from lower jaw by a groove extending along full length of lower jaw. Two lateral lobes closely in contact with each other in females, separated in males by a median interruption on lower jaw, width less than one-third of gape width. Postlabial groove extending anteromedially close to midline of lower jaw, but not meeting with postlabial groove of lower jaw. Lower jaw with a horny cutting margin covered by lower lip. Two pairs of barbels, welldeveloped:rostral pair not extending beyond maxillary barbel base; maxillary pair extending beyond midpoint of eye. Nostrils nearer to anterior margin of eye than to snout tip. Gas bladder bipartite, anterior chamber elliptical, and posterior chamber slender, twice as long as anterior one.

Dorsal fin with three simple and eight branched rays, last one split to base; last simple ray spinous, stout with many serrations along posterior margin; origin equidistant between snout tip and caudal-fin base, or slightly posterior thereto; distal margin slightly concave. Pectoral fin with one simple and 14 or 15 branched rays; tip of depressed fin not extending to pelvic-fin origin, separated from it by 2 to 4 scales. Pelvic fin with one simple and eight branched rays, inserted vertically posterior to base of first branched dorsal-fin ray, extending beyond halfway to anal-fin origin, but not as far as anus; a pelvic axillary scale present, long, extending beyond base of last ray. Anal fin with three simple and five branched rays, its origin equidistant between pelvic-fin origin and caudal-fin base in males, closer to latter in females. Anus located immediately anterior to anal-fin origin. Caudal fin deeply forked, its longest ray twice as long as shortest one.

Body scales moderately large dorsally and laterally, slightly reduced ventrally. Lateral line complete, with 38–41 perforated scales, running medially along caudal peduncle; 5 or 5 1/2 scale rows above lateral line; 3 or 3 1/2 scale rows below it; 11 or 13 predorsal scales, almost of same size as flank scales, not embedded beneath skin. 16 circumpeduncular scales.

Coloration in preserved specimens. In adult females (greater than 100 mm SL), body dorsally brown, ventrally yellow, with six vertical black bars (P1–5 + S3), each bar two scales in width, not extending vertically beyond lateral line; a longitudinal black stripe extending along lateral line on flank. First primary vertical bar (P1) positioned medially above pectoral fin, second primary vertical bar (P2) below posterior end of dorsal-fin base or somewhat anteriorly positioned, third primary vertical bar (P3) posterior to tip of depressed pectoral fin or anterior to anal-fin origin, fourth primary vertical bar (P4) through posterior end of anal-fin base and fifth primary vertical bar (P5) on caudal-fin base, positioned vertically through dorsal and ventral origin of caudal fin. Third secondary vertical bar (S3) positioned above pelvic fin. Vertical bars in adult males fainter than in adult females, or absent. In juveniles (less than 60 mm SL), six vertical bars, each bar two scales in width, extending vertically to second or third scale row below lateral line, with no longitudinal black stripe extending along lateral line on flank.

Dorsal fin with a hyaline distal margin, all rays hyaline, with an oblong, black blotch on each interradial membrane. Caudal fin dusky; pectoral, pelvic and anal fins yellow and grey.

Sexual dimorphism. Sex determination is based on tuberculation, body size, anal-fin shape and length, width of lower lip lobes and body coloration. Tubercles on snout tip and anterior portion of lachrymal larger and more prominent in males than in females. Variable-sized tubercles present on side of branched anal-fin rays, distributed from second to fourth ray in two or three rows at distal portion of each ray in males, absent in females. Anal fin with a truncate distal margin in males, a slightly convex distal margin in females. Anal fin longer in females than in males, with tip of depressed fin reaching ventral origin of caudal fin. Difference in anal-fin length between females and males is given in Table 1. Females slightly larger in size than males. Thirty-three male specimens examined were 69.2–137.9 (mean 108.4) mm SL and 25 female specimens examined were 68.5–155.3 (mean 118.8) mm SL. Two lobes of lower lip closely in contact with each other in females, separated by a median interruption on lower jaw in males. For sexual differences in body coloration, see above.

Distribution. Acrossocheilus kreyenbergii is currently known from the Xi Jiang basin in Guangxi Province, the Xin Jiang, Chang Jiang and Le’an Jiang basins in Jiangxi Province, the Ling Jiang basin in Zhejiang Province, and the lower Yangtz River basin in southern Anhui Province.

Figures

FIGURE 2. Lateral views of body in A. kreyenbergii. (A) IHB 75 V 2912, juvenile, 40.56 mm SL, Jinxiu, Guangxi Province; (B) IHB 0 605415, subadult, female, 81.36 mm SL, Yiyang, Jiangxi Province; (C) IHB 0 605427, subadult, male, 99.23 mm SL, Yiyang, Jiangxi Province; (D) IHB 20080500002, adult, female, 128.3 mm SL, Rongshui, Guangxi Province; (E) IHB 20080500001, adult, male, 124.1 mm SL, Rongshui, Guangxi Province. Scale bar = 10 mm.

FIGURE 3. Lateral views of two syntype specimens of Gymnostoma kreyenbergii: (A) BMNH 1907.11.26.1 – 2 (1), male, 132.9 mm SL; (B) BMNH 1907.11.26.1 – 2 (2), female, 71.1 mm SL. Scale bar = 10 mm.