Dusky smooth-hound fishes is their ability to continually replace the teeth in their upper and lower jaws. Smooth dogfish differ from other sharks because of their 10 rows of flat, blunt teeth. The teeth in the upper and lower jaws are similar in size and are asymmetrical with rounded cusps. These teeth are used to crush and grind food, rather than bite it. Their unique dentition is important for their crustacean-based diet. In smooth dogfish, tooth replacement is related to body growth. They grow about 10 cm per every six rows of teeth replaced. That is an increase of 0.03 mm per
Spotless smooth-hound continental shelf and in semi-enclosed areas of sea at depths down to and possibly as deep as . It is found near the seabed, often over sandy substrates and is thought to feed on crustaceans and other benthic invertebrates. The spotless smooth-hound is viviparous. Males become sexually mature at a length of between and females at . Litter size varies between about five and sixteen pups which are nourished by yolk sac placentas. The gestation period is about ten months and the pups measure about at birth. Maximum recorded age is nine years. The spotless smooth-hound is used for human