Diagnosis |
Diagnosis: The mouth of this species has a more ventral position than that of the other Carasobarbus species, being almost inferior (Ref. 57642). It is the only species of the genus Carasobarbus in which both pairs of barbels are always present, the barbels of the anterior pair being often very short, but not quite rudimentary (Ref. 57642). Carasobarbus exulatus differs from all congeners, except C. fritschii and C. harterti in modally having 9 instead of 10 branched dorsal-fin rays; it differs from C. fritschii and C. harterti in modally having 12 scales around the least circumference of the caudal peduncle vs. 16 and in having 24-32 scales on the lateral line vs. 30-39 and 31-38 respectively (Ref. 94477).
Description: The body is slightly compressed and gives the impression of being heavy and bulky; the dorsal profile is arched and the ventral profile flat; a nuchal hump is present in adult specimens, but absent in juveniles; the body depth is about the same as the head length (Ref. 94477, 113720). The snout is pointed in lateral view; the mouth is curved and ventral; the lower lip is thin and continuous; two pairs of barbels are invariably present, although the anterior pair may well be very small; the eyes are at the end of the anterior half of the head and slightly protuberant (Ref. 113720). The caudal peduncle is slender (Ref. 94477). The dorsal fin has 4 unbranched rays and 7-10 branched rays; the last unbranched ray is strongly ossified and only the tip is flexible, its length is about the same as the head length; the dorsal fin origin is usually slightly in front of the vertical from the pelvic fin origin; the anal fin has 3 unbranched rays and 5-6 branched rays; when reflexed, the anal fin reaches to the base of the caudal fin rays (Ref. 94477, 113720). In the lateral line series there are 24-32 scales; there are 10-12 scales around the least circumference of the caudal peduncle and 4-5.5 scales from the lateral to the dorsal mid-line; between the lateral line and the ventral mid-line there are 3.5-5.5 scales; there are 2-3 scales between the lateral line and the pelvic fin base; the scales on the ventral surface of the fish, especially in the thoracic region, show signs of reduction and in some specimens the region between the pectoral fins is naked (Ref. 94477, 113720). The pharyngeal teeth number 2.3.5-5.3.2 (Ref. 113720). The gill rakers are short, hooked and widely spaced; there are 6-9 gill rakers on the lower limb of the first gill arch (Ref. 113720).
Colouration: Preserved specimens are yellow-brown; have a dark back and a lighter belly, the fins are whitish or greyish (Ref. 94477, 113720). In live specimens and freshly preserved specimens the back and the sides are grey to golden, the belly is yellowish white and the fins are sometimes golden to orange (Ref. 94477). |