The genus Polydactylus is a group of fish commonly known as the Atlantic threadfins. These fish are notable for their elongated bodies, flat heads, and thread-like fins that crouch down to their tails. Though the genus Polydactylus is often referred to by this name, there are several synonyms for this group of fish, including Euleterus, Megalops, and Polydactylys. These synonyms are used to differentiate specific subgroups within the genus, including the West African, Gulf, and Atlantic threadfins. Recognizing these synonyms can help scientists understand the biodiversity and evolution of these fish species and further classify them for conservation efforts.