The historic range of the woundfin, Plagopterus argentissimus, included the lower Colorado and Gila River drainages of Utah, Arizona, and Nevada. Unfortunately, flow regulation, dewatering, and the introductions of nonnative fishes have negatively impacted the woundfin, and the species is now restricted to the Virgin River system. Because of the reduction in woundfin numbers and distribution, the species is Federally listed as endangered.
The woundfin is a small (about two inches in length) minnow usually found in the main channel of swift, turbid, warm streams over sand substrate. Woundfin diets are quite varied, consisting of insects, insect larvae, other invertebrates, algae, and detritus. The species spawns during the spring in swift shallow water over gravel substrate. Eggs are fertilized in the water and then fall to the bottom; no parental care is given to the eggs or young.