Dusky smooth-hound Dusky smooth-hound The dusky smooth-hound ("Mustelus canis"), also called the smooth dogfish or the dog shark, is a species of houndshark in the family Triakidae. This shark is an olive grey or brown in color, and may have shades of yellow or grayish white. Females live to 16 years and males have a lifespan of 10 years. "M. canis" was the first shark recognised to have viral infections. "M. canis" can be known as smooth dogfish, Atlantic smooth dogfish, dusky smooth-hound, grayish, nurse shark, smooth dog, or smooth-hound. It was originally named "Squalls canis". In Latin, "mustelus" translates to weasel
Slender smooth-hound about one-sixth of the total length; the lower caudal fin lobe is indistinct, while the upper lobe has a strong ventral notch near the tip. The skin is densely covered by small, overlapping dermal denticles. The crown of each denticle is mounted on a short stalk and bears three horizontal ridges leading to marginal blade-like teeth, with the central tooth particularly long. This species is plain brownish-gray above and lighter below. It grows up to long and in weight, with females reaching a slightly larger size than males. The slender smooth-hound is likely a schooling species. It preys on a