The Lesser Antillean macaw or Guadeloupe macaw (Ara guadeloupensis) is a hypothetical extinct species of macaw that is thought to have been endemic to the Lesser Antillean island region of Guadeloupe. In spite of the absence of conserved specimens, many details about the Lesser Antillean macaw are known from several contemporary accounts, and the bird is the subject of some illustrations. Austin Hobart Clark described the species on the basis of these accounts in 1905. Due to the lack of physical remains, and the possibility that sightings were of macaws from the South American mainland, doubts have been raised about the existence of this species. A phalanx (toe bone) from the island of Marie-Galante confirmed the existence of a similar-sized macaw inhabiting the region prior to the arrival of humans and was correlated with the Lesser Antillean macaw in 2015. Later that year, historical sources distinguishing between the red macaws of Guadeloupe and the scarlet macaw (A. macao) of the mainland were identified, further supporting its validity.

According to contemporary descriptions, the body of the Lesser Antillean macaw was red and the wings were red, blue and yellow. The tail feathers were between 38 and 51 cm (15 and 20 in) long. Apart from the smaller size and the all-red coloration of the tail feathers, it resembled the scarlet macaw and may, therefore, have been a close relative of that species. The bird ate fruit – including the poisonous manchineel, was monogamous, nested in trees and laid two eggs once or twice a year. Early writers described it as being abundant in Guadeloupe, but it was becoming rare by 1760, and only survived in uninhabited areas. Disease and hunting by humans are thought to have eradicated it shortly afterward. The Lesser Antillean macaw is one of 13 extinct macaw species that have been proposed to have lived in the Caribbean islands. Many of these species are now considered dubious because only three are known from physical remains, and there are no extant endemic macaws on the islands today.

The Lesser Antillean macaw is well-documented compared to most other extinct Caribbean macaws since it was mentioned and described by several contemporary writers. Parrots thought to be the Lesser Antillean macaw were first mentioned by the Spanish historian Gonzalo Fernández de Oviedo y Valdés in 1553, referring to a 1496 account by the Spanish bibliographer Ferdinand Columbus, who mentioned chicken-sized parrots—which the Island Caribs called "Guacamayas"—in Guadeloupe. In 1774, the French naturalist Comte de Buffon stated that the Italian explorer Christopher Columbus had found macaws in Guadeloupe. The French botanist Jean-Baptiste Du Tertre gave the first detailed descriptions in 1654 and 1667 and illustrated the bird and other animals found in Guadeloupe. The French clergyman Jean-Baptiste Labat also described the bird in 1742. Writers such as George Edwards and John Latham also mentioned the presence of red and blue macaws on the islands off America.

The American zoologist Austin Hobart Clark gave the Lesser Antillean macaw its scientific name, Ara guadeloupensis, in 1905, based on the contemporary accounts, and he also cited a 1765 color plate as possibly depicting this species. He wrote that it was different in several ways from the superficially similar scarlet macaw (A. macao), as well as the green-winged macaw (A. chloropterus) and the Cuban macaw (A. tricolor). Clark suggested the species might also have existed on the islands of Dominica and Martinique, based on accounts of red macaws there as well as on Guadeloupe. In his 1907 book Extinct Birds, the British zoologist Walter Rothschild instead claimed each island had its own species, and that the Lesser Antillean macaw was confined to Guadeloupe. In 1908 Clark reclassified the Dominican macaw as a separate species (A. atwoodi), based on the writings of Thomas Atwood.

In 1967, the American ornithologist James Greenway wrote that the macaws reported from Guadeloupe could have been imported to the region from elsewhere by the native population, but this is difficult to prove. Greenway also suggested that the scarlet macaw and the Cuban macaw formed a superspecies with the Lesser Antillean macaw and other hypothetical extinct species suggested for Jamaica and Hispaniola. The British ornithologists Julian P. Hume and Michael Walters proposed in 2012 that the similarity between the Lesser Antillean macaw and the scarlet macaw indicates that they were close relatives, and that the Guadeloupe species may have descended from the mainland macaw. In 2017, the Australian ornithologist Joseph M. Forshaw found the Cuban, the Lesser Antillean, and the supposed Jamaican red macaw (A. gossei) so similar that they could have been the same species transported between islands, or, with macaws that possibly occurred on other islands, been closely related and possibly derived from the scarlet macaw.

A small parrot ulna (a lower arm bone) found on the Folle Anse archaeological site on Marie-Galante, an island in the Guadeloupe region, was assigned to the Lesser Antillean macaw by the ornithologists Matthew Williams and David Steadman in 2001. In 2008, the ornithologists Storrs Olson and Edgar Maíz López cast doubt upon this identification, and proposed that the bone instead belonged to the extant imperial amazon (Amazona imperialis). The size and robustness of the bone was similar to ulnae of the imperial amazon, and though it was worn, the authors identified what appeared to be a notch, which is also present on ulnae of the genus Amazona, but not in the genus Ara. Subfossil remains from the island of Montserrat have also been suggested to belong to the Lesser Antillean macaw. The species was recognized by Birdlife International and the IUCN Red List until 2013, but was not considered valid thereafter.

In 2015, a terminal phalanx bone (ungual claw toe bone) attributable to the genus Ara from south-western Marie-Galante was described by ecologists Monica Gala and Arnaud Lenoble. It was discovered in the Blanchard Cave during excavations in 2013–2014, in a fossil-bearing deposit dating to the late Pleistocene epoch. The deposit was radiocarbon dated to about 10,690 years ago; the earliest evidence of human settlement in the area has been dated to 5,300 years ago. This confirmed that the Guadeloupe region once had an endemic macaw which could not have been brought there by humans. All other macaw bones from the Lesser Antillean islands have been recovered from archaeological sites, and could therefore have been the remains of birds brought there by Amerindians. The size of the phalanx bone matched what was described for the Lesser Antillean macaw by contemporary writers, and the authors therefore correlated the two. They conceded that this connection could only be tentative, as there were no remains of the Lesser Antillean macaw to compare with.

Later in 2015, Lenoble reviewed overlooked historical Spanish and French sources, finding references to mainly red macaws consistent with the Lesser Antillean macaw. The writings of the French missionary Raymond Breton (on Guadeloupe from 1635 to 1654) were especially illuminating, as they showed that both he and the native Island Caribs clearly distinguished between the red macaws of Guadeloupe and the scarlet macaws from the mainland, which supports the idea that the Lesser Antillean macaw represents an independent species. As the Lesser Antillean Carib language had different words reserved for men and women, Breton gave the name of the bird as Kínoulou (♂) and Caarou (♀). Lenoble furthermore concluded that the supposed violet macaw (named Anodorhynchus purpurascens based on accounts of blue parrots from Guadeloupe) was based on misidentified references to the also-extinct Guadeloupe amazon (Amazona violacea), and therefore never existed.