The anal fin has seven rays, while the dorsal has 13 rays. Recent genetic studies have revealed deep, but morphologically cryptic, population subdivision (about 4.5% sequence divergence) between drainages of the ancient Snake River and the Bonneville Basin.
There are seven rays in the anal fin and thirteen in the dorsal fin. Recent genetic investigations have identified substantial, yet hidden by morphology, population differentiation (about 4.5% sequence difference) among drainage areas of the ancient Snake River and the Bonneville Basin.