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
Spotless smooth-hound Spotless smooth-hound The spotless smooth-hound ("Mustelus griseus") is a species of houndshark, in the family Triakidae, found on the continental shelves of the northwest Pacific, between latitudes 40° N and 11° N, from the surface to a depth of 300 m. It can grow to a length of up to . Male spotless smooth-hounds grow to a length of about with females growing to around . The head is short with a fairly long, bluntly pointed snout and the body is slender. The eyes are small and close together. The mouth is long and the lower lip groove is usually