Common smooth-hound on its underneath. It is often confused with the starry smooth-hound which has white spots on its back. The starry smooth-hound can often have faded spots which leads to misidentification. Another shark it is often confused with is the tope shark although the common smooth hound has a larger second dorsal fin. Due to the similarities between the common smooth-hound and other sharks, misidentification occurred for a long time. The common smooth-hound has two dorsal fins, an anal fin, a pair of pectoral fins, a pair of pelvic fins and a heterocercal tail. All of these fins help stabilise the
Humpback smooth-hound the three species it is the humpback smooth-hound that is the main target of the tollo fishery in Peru. Landings averaging 11,000 tons of tollo per year were made in that country between 1965 and 1989, but quantities caught diminished thereafter. A minimum size requirement of was set in 2001 but was pitched so low as to have limited conservation effect. The International Union for Conservation of Nature (IUCN) has rated the status of the humpback smooth-hound as being "vulnerable" and considers more should be done to publicise and enforce the size limit. Humpback smooth-hound The humpback smooth-hound ("Mustelus whitneyi")