Salmonids include trouts, salmons, chars and whitefishes. All members of the family are freshwater or migrate into freshwater to spawn. Salmonids have small cycloid scales, one dorsal fin, an adipose fin and no spines in the fins. Members of this family are often introduced into bodies of water due to their great commercial value.

cisco--Coregonus artedii [state threatened]
lake whitefish--Coregonus clupeaformis
bloater--Coregonus hoyi
blackfin cisco--Coregonus nigripinnis [extirpated]
pink salmon--Oncorhynchus gorbuscha [nonnative]
coho salmon--Oncorhynchus kisutch [nonnative]
rainbow trout--Oncorhynchus mykiss [nonnative]
chinook salmon--Oncorhynchus tshawytscha [nonnative]
round whitefish--Prosopium cylindraceum
Atlantic salmon--Salmo salar [nonnative]

brown trout -- Salmo trutta [nonnative]
The caudal fin of the brown trout has no or very faint spots, and the sides and head of the body have red and black spots. The brown trout was introduced into the United States in the early 1880s. It is a native of Europe. It continues to be stocked in Lake Michigan and other locations in Illinois. The brown trout feeds at night, eating insects, crayfish and fishes. It does not naturally reproduce in Illinois. This fish may reach about three and one-half feet in length. brook trout--Salvelinus fontinalis
lake trout--Salvelinus namaycush