Chitala blanci (d'Aubenton, 1965)
Species overview
A knife fish with concave upper profile of head and humpback, in all characters very similar to Chitala chitala , but with a rather limited distribution on the Indo-Chinese peninsula instead of the Indian Subcontinent. Most obvious character is the pattern of irregular oblique bars and spots on body and anal ans caudal fin and a large round black spot at the base of the pectoral fin which, however it shares with C. lopis. These features are shown by very small specimens (60 mm) and up to the largest ones.
Size observed: 80 cm.
Taxonomic description
-Body laterally compressed, greatest depth above origin of anal fin.
-Head with strongly concave upper profile, above opercular cleft at least two times as deep as above the eye.
-Outline of back strongly convex, hump like.
-Mouth terminal, its edge clearly behind posterior rim of eye.
-Eye rather small. Scales on preopercle of same size as scales of body.
-Opercular cleft long, curved.
-Origin of pectoral fin above level of edge of mouth, end of fin reaching to origin of anal fin.
-Pelvic fin small.
-Anal fin long, 119-131 fin-rays, merging without conspiduous border in caudal fin, 16 fin-rays, its longest fin-rays close to its middle. 81-86 vertebrae.
Can be separated from the other species of its genus only by its coloration which according to Roberts (l.c.) always shows up in fishes raised in fish farms.
-Coloration, no particular indication of ground coloration, probably brownish to silvery and blackish, as in the other species, but with a "strongly marked pattern of irregular oblique bars and spots on the body and on anal and caudal fins. ... Differing from all other species except C. lopis in having a large, round black spot at base of pectoral fin." (Roberts, 1992 and see above.)
Type locality
>Rapids of Mekong river between Laos border and Kratié, northern Cambodja.<
Distribution
>Known only from the mainstream of the Mekong River in Thailand, Laos and Kampuchea.< Species >avoids tributaries and swamps.<