The narrownose smooth-hound (Mustelus schmitti) is a houndshark of the family Triakidae. It is found on the continental shelves of the subtropical southwest Atlantic, from southern Brazil to northern Argentina, between latitudes 30° S and 44° S, at depths between 60 m to 195 m. It can reach a length of 74 centimeters.Narrownose smooth-hounds feed on crabs and probably other crustaceans, and presumably small fishes.