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Virgin River chub usually grow to be less than 13 cm (5.12 in) long. The desquamation of the anterior and ventral body surfaces is likely an adaptation to swift, turbid waters in which it lives. Its coloring is silvery over most of the body.

These fish spawn in June and July when the water temperatures have warmed to about 19 degrees C (66.2 F). At this time they avoid turbid waters, staying in low, clear flows so that eggs are not carried away by the current.

The largest of this species feed on other smaller fish species, but most eat terrestrial and aquatic insects, and plant matter.

The population of Virgin River chub has declined over the last 100 years due to increased agricultural and urban water use, decreased water quality, and the introductiuon of exotic fishes. Decreased water flow leads to overcrowding of fish, resulting in increased predation and spread of disease. There is a population currently being maintained at the Dexter National Fish Hatcheries in Dexter, New Mexico.

These chub are found in runs and pools over subatrates of sand and sediment in physically and chemically unmodified areas of the Virgin River.

1. J. N. Cross. 1978. Status and ecology of the Virgin River chub, Gila robusta seminuda. Southwestern Naturalist. 23 (3): 519-527.
   
2. Mckinley, W. L. & Deacon, J. E. 1991. Battle against extinction. The University of Arizona Press: Tuscon, Arizona.