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Dorsal spines (total): -0; Dorsal soft rays (total): 10-11; Anal spines: -0; Anal soft rays: 8-9; Vertebrae: 34-35. Diagnosis: moderate-sized, robust-bodied species; last dorsal simple ray ossified and serrated; 26-29 lateral line scales; no prominent sheath of enlarged scales at the base of the dorsal fin; fins tinted pinkish-orange; midlateral black stripe extends through the caudal fin to the fork, but does not extend onto the snout (Ref. 75045).
Description: body slightly compressed, maximum depth approximately equal to head length, located before dorsal fin; nape rises in hump behind head, particularly in larger specimens; head moderately deep, four times in standard length; eyes lateral in position, visible from above and below; orbit becoming proportionately smaller in large specimens; snout rounded and short, equal to or slightly shorter than orbit diameter; no tubercles on the head; nostrils small; short tubular anterior naris adjacent to open posterior naris; nostrils level with dorsal margin of eye and separated from orbit by less than one orbit radius; mouth subterminal, crescentshaped and reaching to below anterior border of orbit; lips moderately well-developed; 2 pairs of simple barbels, anterior slightly shorter than posterior, which is approximately equal to orbit diameter; gill cover opening from level with dorsal margin of orbit, attached ventrally close to isthmus; gill rakers short, stub-like and widely-spaced; pharyngeal bones typical of small African Barbus species with 3 rows of peg-like pharyngeal teeth with pointed cusps (formula 5,3,2 2,3,5); 17-19 abdominal vertebrae; 15-17 caudal vertebrae; 9-10 predorsal vertebrae; 12-13 rib pairs; origin of dorsal fin equidistant between tip of snout and base of caudal fin, above or just behind origin of pelvic fins; dorsal fin becomes relatively shorter with increasing size of specimen, from approximately 30% of standard length in smallest specimens to 20% in largest individuals; anteriormost branched ray of dorsal fin longest; distal margin of dorsal fin concave; last unbranched dorsal ray ossified and finely serrated (approximately 30 prominent serrations and up to 40 in total) on its posterior side; pectoral fins reach 2/3 of distance to base of pelvics, with tips rounded and distal margin straight; pelvic fins reach 2/3 of distance to base of anal fin; pelvic fins relatively small and rounded; anal fin short, extending 1/3 length of caudal peduncle; last unbranched ray of anal fin longest, with distal margin straight; outer rays of caudal fin twice length of median rays; caudal fin lobes rounded; caudal peduncle long, length twice depth; anus and genital opening immediately anterior of base of anal fin; gut short, about equal to standard length, in a single simple S-flexure; scales moderately large, cycloid and rounded, well developed in regular rows; scales radially striate with about 10 radii in total; lateral line complete, anteriorly dipping one scale row below the horizontal myoseptum, joining and extending straight along the midline at the anterior end of the caudal peduncle; no sheath of enlarged, elongate scales along base of dorsal fin; short pelvic axil scale present; breast scales well developed; 9-12 predorsal scale rows (Ref. 75045). Coloration: alive: body and head olive dorsally and sides silvery with whitish-gold sheen ventrally; black midlateral stripe bordered with golden yellow; black post-opercular vertical bar present; dorsal fin with dark olive rays and clear membranes; caudal fin colouration similar but with pinkish-orange tinge, particularly on lower half; pectoral, pelvic and anal fins pale brownish-orange tinted distinctly pinkish-orange; iris dark anteriorly and posteriorly, pale yellow ventrally with orange highlight dorsally; specimens from turbid water uniformly pale with faint dark midlateral stripe (Ref. 75045). Preserved specimens: dorsal surface scales densely pigmented with fine melanophores, with a crescent of closely spaced larger melanophores at both anterior and posterior borders of exposed part of scale; pigmentation less intense in centres of lateral line scales and in the row below the lateral line only a few scattered melanophores present on each scale, although anterior crescent is still fairly prominent; in next row below, only a few scattered melanophores present anteriorly and dorsally on each scale; below this, all scales pigment-free except for a few melanophores along the ventral scale row between anal and caudal fins; crescent of dark pigment present behind operculum from lateral line to pectoral fin base; horizontal myoseptum darkly pigmented beneath the scales, forming a fine but fairly intense mid-lateralstripe, most prominent on the caudal peduncle; in many specimens, underlying pigmentation emphasised by additional melanophores along the line on the scales themselves; at base of caudal fin, lateral stripe broadens slightly as a result of heavier scale pigmentation; stripe continues through to posterior margin of caudal fin; mid-dorsal stripe present for full length of body; rays of the dorsal, pectoral and caudal fins lightly pigmented with fine melanophores; pelvics and anal almost pigment free; operculum and snout covered in melanophores, which are more abundant but finer on the snout; both pairs of barbels lightly pigmented (Ref. 75045). |