The longhorn sculpin (Myoxocephalus octodecemspinosus) is a species of marine ray-finned fish belonging to the family Cottidae, the typical sculpins.This species is found in the Northwest Atlantic Ocean.

[2][3] It is a predatory and scavenging fish that can feed on the remains of other organisms.

[4] The longhorn sculpin was first formally described as Cottus 18-spinosus in 1814 by the American physician and naturalist Samuel L. Mitchill with its type locality given as New York.

When the fish is resting on sand or dirt, it is plain in color, but when resting on pebbles, it is variably marked in order to blend in with its surroundings in both scenarios.

[7][8] The range extends from Newfoundland and the Gulf of Saint Lawrence to Virginia.