Diagnosis |
Diagnosis: The possession of a single pair of oral barbels separates Pseudobarbus senticeps from P. skeltoni, P. verloreni, P. burgi and P. burchelli (Ref. 114782). The possession of fewer and larger scales, 25-30 scale rows along the lateral line, separates P. senticeps from P. quathlambae, P. asper, P. swartzi and P. tenuis, which have respectively more than 60, 35-45, 34-37 and 32-37 scale rows along the lateral line; there is overlap in lateral line scales series between P. senticeps, P. afer and P. phlegethon, which have respectively 25-30, 29-35 and 29-37 lateral line scales series (Ref. 114782). A lateral stripe which terminates in a triangular blotch at the base of the caudal fin and longer barbels, reaching or surpassing vertical through the posterior edge of the eye, further separate P. senticeps from P. afer, which barbels do not surpass vertical through the centre of the eye (Ref. 114782). Body colour pattern distinguishes P. senticeps from P. phlegethon, which is characterised by prominent black spots and patches on the body, which are lacking in P. senticeps (Ref. 114782).
Description: A moderately laterally compressed, fusiform species; cross-section of body between pectoral and pelvic fins ellipsoid; dorsal profile of body, in lateral view, convex from snout tip to dorsal fin origin, straight and descending from dorsal fin origin to caudal fin insertion; ventral profile, in lateral view, more or less straight or slightly convex from snout tip to anal fin origin, slightly concave and ascending from origin of anal fin to caudal fin insertion; body deepest around anterior bases of dorsal and pelvic fin origins, progressively becoming narrower from anal fin origin towards the caudal fin; caudal peduncle length almost twice as its depth, cross-section ellipsoid (Ref. 114782). Snout blunt or obtusely pointed; mouth terminal, sickle shaped, its corner not reaching vertical through anterior margin of eye; a single pair of well developed, long and slender maxillary barbels present, barbel length longer than orbit diameter in most specimens; eyes moderately large, 23.5-29.5% of head length, dorso-laterally positioned, and located closer to tip of snout than posterior margin of gill cover; orbit diameter shorter than snout length. Lateral line with 25-30 scales to end of hypural plate, 1-2 more scales to base of caudal fin; 4-5 scale rows between lateral line and dorsal fin origin; 3-4 rows between lateral and pelvic fin origin; 3-4 scale rows between lateral line and anal fin origin; 12-15 predorsal scale rows; 10-12 circumpeduncular scales; breast scales reducde and embedded, giving a naked appearance to the region between the isthmus and base of pelvic fins; elongated or triangular pelvic axillary scales absent; scales between the nape and dorsal fin origin reduced and embedded (Ref. 114782). Dorsal fin with 3-4 unbranched rays and 7 branched rays, origin slightly posterior to pelvic fin origin; tip of adpressed dorsal fin reaches within 2-3 scales to vertical through posterior base of anal fin, distal margin straight; pectoral fin with 13-15 rays, fan shaped, larger in males than females, tip of adpressed pectoral fin reaches and surpasses base of pelvic fin in males, reaches 2 scales to base of pelvic fin in females; pelvic fin with 8-9 rays, origin slightly in front of dorsal fin origin, outer margin slightly convex, its tip reaching anterior origin of anal fin when depressed in males and reaches 2-3 scales to anal fin origin in females; anal fin with 3 simple rays and 5 branched rays, distal margin almost straight to slightly convex or straight, origin closer to anterior base of pelvic fin than base of caudal fin; caudal fin is forked, with 10+9 principal rays (Ref. 114782). Total vertebrae including Weberian apparatus 35-38, predorsal vertebrae including Weberian apparatus 11-13; precaudal vertebrae including Weberian apparatus 18-19, caudal vertebrae 16-18 (Ref. 114782).
Colouration: Dorsum and sides dark brown, belly and underparts off-white or silvery, operculum metallic gold, base of fins bright red; vague lateral stripe terminating in a triangular blotch at the base of the caudal fin (Ref. 114782). Dorsal surface of alcohol preserved specimens dark grey or black, sides and belly lighter; distinct black lateral stripe from posterior margin of operculum terminating into a black triangular blotch of pigment at the base of the caudal peduncle; red pigmentation at the base of fins disappears in preserved specimens (Ref. 114782). |