Appearance
Shiner perch is similar to tule perch; it is deep-bodied with a dusky greenish back and silvery sides that have a pattern combining fine horizontal bars with three broad yellow vertical bars. Breeding males turn almost entirely black, the barred pattern being obscured by dark speckles. Shiner perch is distinguished from tule perch by having fewer dorsal fin spines, just 8–9 vs the 15–19 of the tule perch. The rayed part of the dorsal fin has 18 to 23 rays. The anal fin has 3 spines followed by 22–25 rays.
Shiner perch can reach a maximum length of 21 centimetres (8.3 in), but are most commonly under 10–15 centimetres (3.9–5.9 in) in total length. Shiner perch mature soon after birth, but females often wait until one year of age before spawning. Breeding males can turn almost completely black.

