It has a longer pelvic fin, and a smaller more oblique mouth. Big Spring spinedace are bright, silvery colored with some specimens lemon to yellow in the axils of the paired fins, on the basal part of the anal fin, near the upper side of the shoulder girdle, on the verticle preopercle, and above the mouth. Most spawning of the Big Spring spinedace occurs from March through June, with some continuing sporadically into July. These fish are sexually mature after about a year. Females generally produce from 380-640 eggs during spawning, with older females sometimes producing two complements of ova in one breeding season.
Adults are oportunistic feeders, but prefer insects.
Plant matter is consumed in late summer to fall when insect larvae are scarce. Large, wet meadow fed primarily by Big Spring, northeast of Panaca, Lincoln County, Nevada. The name pratensis is derived from the Latin, meaning pertaining to or growing in a meadow, in reference to the extensive meadowlands of Big Spring References LaRivers, Ira. Fishes and fisheries of Nevada. Lee, David S. 1981.