Squalus formosus (Taiwan dogfish or Taiwan spurdog) is a species of shark in the genus Squalus. It was accidentally found in Taiwan's Tashi fish market by William Toby White and a colleague of the CSIRO in Hobart, Australia. They named it S. formosus ("Formosa" being a former name for Taiwan). It has also be recorded from the coast of Japan.Sharks now identified as Squalus formosus had earlier been classified as Squalus blainville, a species that is no longer considered to occur in Taiwan.