Slender smooth-hound journal "Transactions of the Royal Society of New Zealand". Garrick named the species "Triakis attenuata", in reference to its extremely slender ("attenuate") body. In 1973, Leonard Compagno proposed a separate genus for the slender smooth-hound: "Gollum", after the character in J. R. R. Tolkien's "The Lord of the Rings", "to whom this shark bears some resemblance in form and habits." He placed "Gollum" with the finback catsharks (Proscylliidae), but also noted its many anatomical similarities to the false catshark ("Pseudotriakis microdon"). At the time, Compagno chose to maintain "Pseudotriakis" as the sole member of the family Pseudotriakidae because of its
Dusky smooth-hound replaced tooth. Teeth are replaced at a rate of one row per 10 to 12 days. "M. canis" feeds mostly on crustaceans, polychaetes, and mollusks. Smooth dogfish also eat squid, worms, small fish, razor clams, and occasionally garbage. They are nocturnal scavengers and opportunistic predators. Their nocturnal activity helps them to take advantage of concentrations of crustacean prey. The mating season of smooth dogfish is from May to June. They are viviparous and have a yolk-sac placenta. Females can store sperm up to a year, but how long it can be used is not known. Their gestation period is 10