SCIENTIFIC NAME: Erimyzon tenuis
CHARACTERISTICS: The largest chubsucker in Alabama, the sharpfin chubsucker usually has a pointed dorsal fin, but the fin may become rounded on large individuals. The anal fin is almost always pointed, and when depressed, its longest rays extend beyond the caudal fin base. The body has 40 to 45 lateral scales but no lateral line. Large breeding males have four large, often hooked tubercles on each side of the head. Young sharpfins are brown on the back and cream on the venter, with a light yellow lateral band above a dark lateral stripe extending from the snout to the caudal fin base. As the fish ages, the lateral stripe disappears. Many scales are edged in black, giving them a diamond-shaped appearance. Fins are dusky overall, with rays outlined in black.
ADULT SIZE: 9.8 to 16 in (250 to 406 mm)
DISTRIBUTION: Most Alabama collections are from the Fall Line Hills and Southern Pine Hills of the East Gulf Coastal Plain. Sharpfins are particularly widespread and often abundant in the Escatawpa and Perdido drainages and freshwater tributaries to Mobile Bay.
HABITAT AND BIOLOGY: Sharpfin chubsuckers are most common in swamps, small or medium-sized streams, and coastal river backwaters with slow to moderate currents and sandy substrates often lightly covered with silt. Sharpfins congregate along undercut banks and around aquatic vegetation and submerged brush piles. Little is known about the species’ life history in Alabama. Our collection of tuberculate, gravid individuals in the Styx River in 1991 indicates that spawning occurs in late March and April. Young sharpfins remain in schools until they are 4 or 5 inches long and probably consume zooplankton and small aquatic insect larvae. Adults eat larger aquatic larvae. Judging from the adult size of this and the two other Erimyzonspecies in Alabama, we believe that the sharpfin chubsucker lives for seven to eight years.
REMARKS: The type locality is given as “Mobile, Alabama.”
ORIGINAL DESCRIPTION: Agassiz described the sharpfin chubsucker in 1855.
Erimyzon means to suck.
Tenuis means thin, presumably referring to this species’ elongate anal fin.
The copyrighted information above is from Fishes of Alabama and the Mobile Basin.