The Virgin chub, Gila seminuda, is an extremely rare minnow, occurring only in the Virgin River system of southwestern Utah, southern Nevada, and northwestern Arizona. In Utah, the species is restricted to limited areas of the main-stem Virgin River. Virgin River chub have been drastically reduced in numbers and distribution from historic times, primarily due to flow alterations and exotic fishes (that compete with and prey upon Virgin River chub). Consequently, the Virgin River chub is Federally listed as an endangered species.
Virgin River chub are opportunistic feeders, consuming zooplankton, aquatic insect larvae, other invertebrates, debris, and algae. Interestingly, the diet of many adults is composed primarily of algae, whereas the diets of younger fish contain more animal matter. The species spawns during late spring and early summer over gravel or rock substrate. No parental care is provided for the eggs, which hatch in one week or less. Virgin River chub are usually associated with deep, protected areas of swift water.