occurs from New Smyrna Beach in Florida south and west into the Gulf of Mexico coast of the United Statesto the Yucatan Peninsula in Mexico. It is absent from the northern part of the Yucatan Peninsula and from Cuba. Vagrants stray as far north as Long Island. Habitat and biology The Atlantic threadfin occurs over sandy or muddy bottoms and on beaches, commonly being observed in the surf zone. It occurs at depths between in the Gulf of Mexico but peak numbers are found at depths of . Young specimens, of lengths less than have been taken from the surface of the Gulf of Mexico where the sea was . Sexual maturity is reached at total lengths between , when they are around 7 to 9 months of age. Spawning probably occurs in the Gulf of Mexico, off Louisiana and Texas and mainly takes place between mid-December and mid-March and lasts between 45 and 120 days overall. The 2-4 month old larvae live in waters shallower than , dispersing towards deeper waters in the early summer. They typically live no longer then 1 year but may be longer in fish that survive their first pelagic spawning. Species description The Atlantic threadfin was originally formally described as Polynemus octonemus in 1858 by Charles Frédéric Girard with the type locality of Brazos Santiago, and Galveston, Texas. References Atlantic threadfin Taxa named by Charles Frédéric Girard Fish described in 1858