Key to the Species of Cyprinidae

22a. (From 20b.) Eye small, positioned laterally, diameter (A) going more than 2 times into snout length (B); mouth subterminal; barbel small; anal rays usually 7, pharyngeal teeth 0, 4-4, 0, or 1, 4-4, 1.
Genus Nocomis

22b. (From 20b.) Eye positioned somewhat dorso-laterally and large, diameter (A) going 2.0 or less into length of snout (B); mouth obviously inferior and with one or more large barbels; barbels often visible without magnification; anal rays usually 7 or 8, pharyngeal teeth 1, 4-4, 1, or 0, 4-4, 0.
Genus Macrhybopsis