The Live Sharksucker or Slender Sharksucker, Echeneis naucrates, is a species of marine fish in the family Echeneidae Echeneidae. A live sharksucker is known to attach itself temporarily by its modified dorsal fin used as a sucking disc to various hosts, such as shark, rays, large bony fishes, sea turtles, whales, dolphins, ships, and even sometimes scubadivers.