Percopsis omiscomaycus, also known as the trout-perch, the grounder or the sand minnow, is one of two species in the family Percopsidae.

These are freshwater fish that prefer clear to slightly turbid water, and are found in rivers and lakes throughout North America.

[3] They are an important source of food for many predator fish such as walleye, northern pike, and lake trout.

They are overall silvery or nearly transparent in appearance with rows of dark spots on along the sides of their bodies both along their lateral line and above it.

They also have an adipose fin, similar to trout, which helps to distinguishes them from their look-alike species, the yellow perch and the walleye.

The trout-perch is found throughout North America, from Canada and Alaska to the Potomac River basin in Virginia.

Spawning sites consist of sandbars and rocks in lakes or on gravel or sand in tributary streams.

A study was conducted in Saginaw Bay, Lake Huron to learn about the ecological role of the trout-perch.

An important finding referred to the energy content of the trout-perch, which was higher than other similar species.

[5] A study found that this strain of protist produces smaller (13–14.5 micrometres long vs 15–17 micrometres long), yet identically-shaped (narrow pyriform) spores than the original strain of protozoa and affects primarily within red and white muscle fibers and only rarely among the subdermal connective tissue in the trout-perch.