SCIENTIFIC NAME: Moxostoma duquesnei
CHARACTERISTICS: The maximum depth of this slender-bodied redhorse goes 3.7 to 4.4 times into its standard length. The caudal peduncle is long and slender. The dorsal fin generally contains 12 or 13 rays, and its free margin is straight or slightly convex. The black redhorse is the only Moxostoma that has 10 pelvic fin rays; all other species have nine. The lateral line is complete, with 44 to 47 scales. Upper and lower lips are plicate, and their lobes meet at a very obtuse angle. The back is olive to brown, the sides silvery to light tan, and the venter cream. In adults, the lower fins are yellow to reddish orange, and the dorsal and caudal fins are olive or slate. Some fish have a pale reddish tail. See Lesueur (1817b) for original description. Jenkins (1970) notes that the Mobile basin population is distinct.
ADULT SIZE: 10 to 15 in (254 to 380 mm)
DISTRIBUTION: The black redhorse has an interesting distribution in Alabama. Collection locations occur above and below the Fall Line in the eastern Mobile basin but are lacking in the western portion. The species’ occurrence in the headwater tributaries to the Sipsey Fork of the Black Warrior River system could be the result of faunal exchange with Bear Creek of the Tennessee River drainage. Populations in eastern tributaries to the Locust Fork seem to indicate an exchange with the Cahaba or Coosa river systems.
HABITAT AND BIOLOGY: Most collections are from medium-sized or small streams having moderate to swift currents and rock, gravel, and sand substrates. We have observed groups of black redhorses assembled for spawning in April and May. Males collected in a Coosa River tributary in Etowah County in early May were running milt on light pressure. R. D. Suttkus reports collecting males running milt and females running eggs in 57ºF (14ºC) water at a tributary of Souwilpa Creek, Choctaw County, on 9 April 1988. Bowman (1970) notes that male black redhorses select spawning habitats with precise concentrations of fine and coarse gravel and sand at depths of 12 to 24 inches. Two males usually spawn with a single female. Adults reach sexual maturity at three years of age and can live for up to 10 years. Black redhorses consume a variety of benthic invertebrates, especially crustaceans and aquatic insects.
ORIGINAL DESCRIPTION: Lesueur described the black redhorse in 1817.
ETYMOLOGY:
Moxostoma means mouth to suck.
Duquesnei is named for Fort Duquesne, Pennsylvania, the type locality.
The copyrighted information above is from Fishes of Alabama and the Mobile Basin.
