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
Spotless smooth-hound longer than the upper one. The teeth are molar-like with low cusps. Both the dorsal fins have a curved trailing edge and the distance separating them occupies about 20% of the total length of the fish. The dorsal surface and flanks are grey or greyish-brown and the ventral surface is paler. The colour is uniform and there are no spots or bands of darker or lighter colour. The spotless smooth-hound is found in the temperate and tropical Pacific Ocean between 40°N and 11°N, off the coast of Vietnam, Japan, China and Taiwan, and possibly the Philippines. It occurs on the