The Horsehair eel (Gordiichthys irretitus) is an eel in the family Ophichthidae (worm/snake eels). It was described by David Starr Jordan and Bradley Moore Davis in 1891. It is a marine, tropical eel which is known from the western central Atlantic Ocean, including Florida, USA, the Gulf of Mexico and Puerto Rico. It dwells at a depth range of 90 to 200 metres (300 to 660 ft), and inhabits sand and mud substrates. Males can reach a maximum total length of 76 centimetres (30 in).