Etheostoma is a genus of small freshwater fish in the family Percidae, and within the sub-family Etheostomatinae, native to North America. Most are restricted to the United States, but species are also found in Canada and Mexico. They are commonly known as darters, although the term "darter" is shared by several other genera. Many can produce alarm pheromones that serve to warn nearby fish in case of an attack.

Etheostomatinae is a species-rich subfamily of freshwater ray-finned fish, the members of which are commonly known as the darters. The subfamily is part of the family Percidae which also includes the perches, ruffes and pikeperches. The family is endemic to North America. It consists of three to five different genera and well over 200 species. A common name for these fish in southern Indiana is pollywog.