Bonytail is the most critically endangered of the Colorado River's native fish, with no reproducing populations in the wild. A number of hatcheries have refuge populations of the species. These streamlined chub have large fins and are powerful swimmers. They reach a maximum length of 22 inches (550 mm). They likely inhabited areas of moderate current in the mid part of the river channel. Bonytails are closely related to humpback and roundtail chubs.