Saint Croix Macaw - Taxonomy

Taxonomy

Wetmore placed the Saint Croix Macaw in the macaw genus Ara based on a single tibiotarsus, a placement confirmed by Olson who reexamined the bone. The discovery of a second specimen by Máiz López at Puerto Rico consisting of several bones confirmed this placement. The Saint Croix Macaw is distinguished from other macaws because of the intermediate size of the tibiotarsus and carpometacarpus. Olson and Máiz López determined that the size of this species is only comparable to geographically distant macaws, namely the Lear's Macaw (Anodorhynchus leari) from Brazil and the Blue-throated Macaw (Ara glaucogularis) from Bolivia. Their detailed analysis of these and the other bones showed distinct differences from those species, particularly from the genus Anodorhynchus. Based on this, authorities generally recognize the Saint Croix Macaw as a valid species.

The Saint Croix Macaw and the smaller Cuban Red Macaw (Ara tricolor) are the only two Caribbean macaw species that have been described based on physical remains. In addition, seven entirely hypothetical extinct macaw species from various Caribbean islands have been described based only on written accounts. Of the hypothetical species, the geographically nearest range is of the Lesser Antillean Macaw (Ara guadeloupensis) from Guadeloupe. According to Wetmore, taxonomic affinities with these hypothetical extinct species are unknown.