The smooth dogfish is a small, shark found in shallow waters from Atlantic Ocean from Canada to southern South America.
Identification keys are no spots on dorsal fin. Two dorsal fins with the second dorsal is very large, almost as big as the first dorsal. The dogfish's teeth are very small and flat. Large catlike eyes. A spiny dogfish, differs in having larger eyes and a sharp spine in front of each dorsal fin. The tail asymmetrical as both lobes are different sizes.
The dogfish is one of the relatively few sharks that can actually change the color of its skin to match its surroundings. It changes only to a lighter or darker shade and not spots and such like a flounder would do.
Dogfish feed on small crabs and lobsters, fish or basically anything it can scavenge. Their teeth are designed for crushing crabs not riping flesh.