Rhodeus is a genus of cyprinid fish, consisting of 22 species called bitterlings. The scientific name is derived from the Greek word rhodeos, meaning "rose". Most species in the genus are restricted to Asia, but two species are found in Europe (R. amarus and R. meridionalis).Bitterlings are short-lived species, generally surviving only about five years. Their maximum size is 11 cm, but they are usually much shorter.