Description: A small (maximum length of 7.5 cm [3.0 in.]) fish with a
slender, fusiform body, and a flattened head and belly. The overall color is silvery. The mouth is large, subterminal, and there is a small maxillary
barbel at the corner of the mouth. These fish have no scales. The caudal
fin is large and deeply forked. The name of this species refers to the two
bony rays that extend into the anterior tip of the dorsal fin and form a sharp spine.
Diet: Omnivorous. Feeds in the water column and on the bottom consuming small invertebrates, algae, and detritus.
Habitat: Most often found in or adjacent to swift, turbid, shallow channels with sandy substrates, or in waters adjacent to riffles. Young stay at the edge of streams in shallow backwater areas.
Range: This species formerly was widespread throughout the larger
rivers and streams in the lower Colorado River Basin (i.e., the Colorado,
Verde, Salt, Gila, and Virgin rivers). Now occurs only in the Virgin River
from Halfway Wash below Riverside, Nevada, to Pah Tempe Spring (just
above LaVerkin, Utah).
Special Remarks: Federally Listed as Endangered.