The streamertails are hummingbirds in the genus Trochilus that is endemic to Jamaica. It is the type genus of the Trochilidae family. Today most authorities consider the two taxa in this genus as separate species, but some (e.g. AOU) continue to treat them as conspecific, in which case scitulus is a subspecies of T. polytmus. A wide range of common names apply to this combined species, including green-and-black streamertail, Jamaican streamertail or simply streamertail. The name streamertail is a reference to the greatly elongated rectrices of the males.