The houndfish, Tylosurus crocodilus, is a gamefish of the family Belonidae. It is the largest member of its family, able to grow up to 5 feet (1.5 m) and reach 10 pounds (4.5 kg). It is also often called the Crocodile Needlefish. While the Houndfish has no spines, its dorsal fin has 21–25 soft rays, and its anal fin has 19–22. They are also known to have 80–86 vertebrae.
A key way of distinguishing the houndfish from other members of the Tylosurus genus is that the houndfish’s teeth point anteriorly when the fish is a juvenile. The teeth of other species are straight at all ages.