Systematics

Currently the Caribbean Martin is considered to be monotypic. Previously, this taxon had a varied taxonomic history. It has been considered to be conspecific with Purple Martin (Progne subis), together with the taxa sinaloae (now Sinaloa Martin Progne sinaloae) and cryptoleuca (now Cuban Martin Progne cryptoleuca) (Hellmayr 1935); included with sinaloae and cryptoleuca as one of three taxa recognized as a species (Snowy-bellied or White-bellied Martin Progne dominicensis), separate from Purple Martin (e.g., Peters 1960, Phillips 1986, Turner and Rose 1989); or together with sinaloae in a species separate from both Purple and Cuban martins (Zimmer 1955). See Systematics.

The taxon dominicensis has been treated treated as a subspecies of Purple Martin (Progne subis); as a subspecies of other species of martin; or as a separate species (see Geographic Variation).  An analysis of both mitochondrial and nuclear DNA sequence data across Progne  shows that dominicensis, cryptoleuca, and sinaloae belong to a clade of Middle American taxa, together with the Middle American populations of the Gray-breasted Martin (Progne chalybea) (Moyle et al. 2008). Within this clade, sinaloae is sister to the Middle American populations of chalybea, while dominicensis and cryptoleuca are sister to one another. Consequently sinaloae is not conspecific with cryptoleuca or dominicensis (contra Zimmer 1955, Peters 1960, Phillips 1986, Turner and Rose 1989).  There is relatively little genetic differentiation between dominicensis and cryptoleuca (e.g., cytochrome b of the two taxa has diverged by only 1.2%), but allopatry of these two taxa, as well as the plumage differences (especially in the male), support the recognition of both taxa as species (Moyle et al. 2008).

Within the swallows Hirundinidae, analysis of mitochondrial and nuclear DNA sequence data shows Progne falls within one of two major clades; the sister taxon to Progne is the genus of New World rough-winged swallows, Stelgidopteryx (Sheldon et al. 2005).