Author: Müller and Henle, 1837
Diagnostic Features:
Snout relatively long, nostrils subterminal and well separated from snout tip. Eyes and supraorbital ridges hardly elevated. Mouth slightly closer to eyes than snout tip. Lower labial folds usually connected across chin by a dermal fold. Pectoral and pelvic fins relatively thin, not heavily muscular. No black hood on head or large dark spot or spots on sides of body above pectoral fins.
Remarks:
The arrangement of this genus follows Garman (1913) and Fowler (1941). The genus is long overdue for a detailed systematic review from a large number of specimens from different localities, and the arrangement of the genus presented here is very tentative. The six species recognized here are probably valid, but there may be additional species that are being confused with the valid ones (especially with C. griseum and C. punctatum).