This fish is about 11 centimeters long. The lower parts of its sides are red, giving rise to its name, and the upper parts of its sides are dark green.
The rosyside dace is native to parts of the southeastern and eastern United States, including the Delaware River drainage, the Savannah River drainage, and the Ohio River basin. It is thought to have been introduced in western Virginia.
Additional field notes
Several structural features help identify a rosyside dace when breeding colors are weak.
Sources: Clinostomus funduloides species summary
Identification beyond red coloration
FishBase describes a large, slanting mouth, pointed snout, forked tail, and small scales. The dorsal fin begins behind the pelvic-fin origin. The lateral line curves downward and is complete, with 43–57 scales reported along it.
Color changes with breeding condition: males can have a dark blue back and brick-red lower sides, while other fish show more subdued silver, green, and yellow-gold areas. The mouth, fin positions, and scale pattern therefore provide clues that remain useful when a fish does not show the strongest red colors.
Sources: Clinostomus funduloides species summary
Guide sources
Research reviewed 2026-10-19.
Article text: Wikipedia contributors, Rosyside dace (source revision). Licensed under CC BY-SA 4.0. Retrieved 2026-10-11.
Diet and feeding
The FishTraits compilation records these diet categories for this species: algae or phytoplankton; invertebrates or larval fish; fish or frog eggs. These are broad categories, not a claim that every individual consumes every example in a category.
Reported feeding positions include surface or water-column feeding. The compilation combines published observations; diets can vary with age, locality, and available food.
Habitat preferences
Reported habitat associations include creeks.
The source records associations with gravel, cobble, boulders. An association indicates reported use, rather than an exclusive requirement.
Reproduction and parental care
The compilation reports a representative maturity age of 2 years. Its maturity field summarizes mean, median, or modal estimates, usually for females; male estimates can be used when female data are unavailable. It is not a fixed age at which every fish first breeds.
Recorded spawning months are May for the source’s reporting region (NC). This is a regional calendar, not a range-wide schedule.
The reproductive-guild classification includes hiding a brood without subsequent guarding.
Size and recorded longevity
FishTraits reports a maximum total length of 11 centimetres. Some entries use an estimated asymptotic length; this value should not be treated as a certified record catch.
Recorded longevity in the compilation is 4 years. Wild observations were preferred, but captive records were accepted where wild records were unavailable, and unspecified records were assumed wild. The value is not a guaranteed wild lifespan or an aquarium life expectancy.
Native range
Atlantic Slope (mostly above the Fall Line) from lower Delaware River drainage, Pennsylvania, to Savannah River drainage, Georgia; Ohio River basin, West Virginia, Virginia, southern Ohio, Kentucky, Tennessee, North Carolina, Alabama, and Mississippi. Absent in Ohio River basin between central Ohio and Cumberland River (including most of Kentucky) (Page and Burr 1991).
