Pseudecheneis, Blyth, 1860

Zhou, Wei, Li, Xu & Yang, Ying, 2008, A Review Of The Catfish Genus Pseudecheneis (Siluriformes: Sisoridae) From China, With The Description Of Four New Species From Yunnan, Raffles Bulletin of Zoology 56 (1), pp. 107-124 : 121-122

Key to Pseudecheneis from China

1. Presence of 14–21 transverse ridges (lamellae) on thoracic apparatus; snout rounded and pointed, the ratio of snout width at mouth corner to distance between pectoral fin base smaller than 0.75; caudal peduncle depth 11.5–24.5% in caudal peduncle length, 3.3–5.7% SL; yellow spots of caudal fin connected each other, forming an entire patch, or only one sport at lower lobe isolated from the big patch; body covered with tubercles, and tubercle density at caudal peduncle more exiguous than that of occipital; outer teeth of premaxillary tooth band two or four ................................................................... 2

– Presence of 9–13 transverse ridges (lamellae) on thoracic apparatus; snout wide and flat, the ratio of snout width at mouth corner to distance between pectoral fin base larger than 0.75; caudal peduncle depth 29.4–46.7% in caudal peduncle length, 6.1–9.3% SL; caudal fin with four yellow spots, isolated each other, not connected; body covered with tubercles, and tubercle density at caudal peduncle denser than that of occipital; outer teeth of premaxillary tooth band six or eight (Red River drainage) .................................................................. P. paviei

2. Pectoral fin longer, extending beyond pelvic fin origin .... 3

– Pectoral fin shorter, just extending to pelvic fin origin .... 6

3 Body colour uniform, without yellow spots or patches; maxillary barbel long, reaching level of gill opening (middle and upper Lancangjiang) .............................. P. immaculatus

– Body with yellow spots and patches; maxillary barbel short, not reaching level of anterior orbital margin ....................... 4

4 Body without pale colored spots or patches after dorsal fin origin (Yunnan) ..................................................... P. tchangi

– Body with pale colored patches at origin and end of dorsal fin, origin and end of adipose fin, base of caudal fin .............. 5

Propseudecheneis tchangi – Hora, 1937: 348–350, Fig. 11 (Yunnan).

Pseudecheneis sulcatus – Chu, 1982: 431 (in part); Chu, Mo & Kuang, 1990: 196–197 (in part); Chu & Mo 1999: 153 (in part).

Pseudecheneis tchangi – Thomson & Page, 2006: 61 (Red River drainage, Yunnan of China).

Material examined. – IZCAS 20010 (original No 12016 in Zoological Museum of Fan Memorial Institute of Biology), 1 ex., holotype, 120mm SL, Yunnan, China (photograph examined) .

Diagnosis. – Pseudecheneis tchangi is distinguished from all other congeners except P. immaculatus in lacking yellow spots or patches on adipose fin base and caudal peduncle (vs. having). And it is distinguished from other congeners except P. immaculatus and P. longipectoralis in having longer pectoral fin, extending to pelvic fin base (vs. not extending). It differs from P. immaculatus and P. longipectoralis in having a yellow, triangular patch at occipital (vs. lacking).

Distribution. – This species was described from Yunnan, but its exact locality is not known.

5 Pelvic fin not reaching anus (Brahmaputra drainage) ............. ................................................................................. P. sulcata

– Pelvic fin reaching anus (branches of Nujiang River drainage) .................................................................... P. longipectoralis

6 Length of caudal peduncle bigger than 30% SL; shortest ray of caudal fin about 50% of longest ray; caudal peduncle without tubercles ................................................................................ 6

– Length of caudal peduncle smaller than 30% SL; shortest ray of caudal fin about 75% of longest ray; caudal peduncle with obvious tubercles .................................................................. 7

7 Yellow spots at dorsal fin origin isolated as two ovoid spots; head length 20.1–23.7% SL, postorbital head length 8.5–11.4% in head length, and body depth 67.1–88.5% in head length (middle and lower reaches of Longchuanjiang, Irrawaddy River drainage) ................................................................ P. stenura

– Yellow spots at dorsal fin origin connected as a saddle patch; head length 14.9–18.6% SL, postorbital head length 4.5–5.9% in head length, and body depth 73.9–112.2% in head length (upper of Longchuanjiang, Irrawaddy River drainage) ......... ................................................................................ P. gracilis

8 Posttemporal with a small yellow ovate spot; yellow spots at dorsal fin origin connected as a saddle patch .................... 8

– Post-temporal without a small yellow ovate spot; yellow spots at dorsal fin origin isolated as two ovoid spots (Nujiang River drainage) .................................................... P. paucipunctatus

9 Occipital with a small, obvious, yellow triangular patch; body only covered rounded tubercles, which gradually decreasing in density from occipital to caudal peduncle (Irrawaddy River) .......................................................................... P. brachyurus

– Occipital without spot or patch; body covered some longitudinal tubercles among rounded tubercles, which distributed uniformly (lower and middle of Lancangjiang) .. .......................................................................... P. sulcatoides

Figures

Fig. 11. Map showing distribution of Pseudecheneis paucipunctatus, P. paviei, P. stenura, P. sulcata and P. sulcatoides.