Longnose dace

Longnose dace can be mistaken for suckers because of their subterminal "sucker-like" mouth. However, longnose dace (like all members of the family cyprinidae) lack small fleshy projections, called papillae, on their mouths. Juveniles have a black lateral line that extends from the beginning of the eye to the caudal fin that fades as the fish matures. The lateral line in juveniles is not present in all populations. In adults, the dorsal side is dark green to black, the lateral side is darkish to silvery with mottling often present, and the ventral side is pearly. Both adult males and females may have bright orange-reddish colouration at the base of pectoral, pelvic, and anal fins and on the upper lip. This colouration is typically associated with breeding males in the subspecies Rhinichthys catarace catarace, but the validity of this subspecies has yet to be confirmed. Museum specimens of females also show intense orange-reddish colouration at the base of the fins and upper lip, therefore colouration is not an accurate predictor of sex. The maximum length of longnose dace is 170 mm, but they are usually less than 100 mm.

Longnose dace can be mistaken for suckers because of their subterminal "sucker-like" mouth. However, longnose dace (like all members of the family cyprinidae) lack small fleshy projections, called papillae, on their mouths. Juveniles have a black lateral line that extends from the beginning of the eye to the caudal fin that fades as the fish matures. The lateral line in juveniles is not present in all populations. In adults, the dorsal side is dark green to black, the lateral side is darkish to silvery with mottling often present, and the ventral side is pearly. Both adult males and females may have bright orange-reddish colouration at the base of pectoral, pelvic, and anal fins and on the upper lip. This colouration is typically associated with breeding males in the subspecies Rhinichthys catarace catarace, but the validity of this subspecies has yet to be confirmed. Museum specimens of females also show intense orange-reddish colouration at the base of the fins and upper lip, therefore colouration is not an accurate predictor of sex. The maximum length of longnose dace is 170 mm, but they are usually less than 100 mm.