Etheostoma

Etheostoma is a genus of freshwater fishes in the perch family Percidae, commonly known as darters. It is the largest genus of darters, with more than 150 described species, native to North America from southern Canada to the Gulf of Mexico. These small, elongated fishes typically measure a few centimeters and inhabit fast-flowing streams and rivers with rocky or gravel substrates.

Etheostoma species are benthic feeders, consuming small invertebrates such as aquatic insects and crustaceans. They commonly occur in riffles and runs where substrate complexity provides shelter. Reproduction is seasonal; males establish and defend nests in gravel or crevices, females lay eggs in or near the nest, and males guard the clutch. Breeding males often show bright coloration, while females remain more cryptic.

The genus occurs across eastern and central North America, including Gulf Coast drainages and the Mississippi River basin. Habitats have suffered from sedimentation, pollution, and water withdrawals, threatening several species. Some taxa are regionally listed as threatened or endangered, while others are of least concern. Darters are sensitive indicators of stream health.

Taxonomy: Etheostoma belongs to the subfamily Etheostomatinae within Percidae. It is highly diverse, with taxonomic relationships that are complex and subject to revision. Notable species include the rainbow darter (Etheostoma caeruleum) and the orangethroat darter (Etheostoma spectabile).