Hypothetical extinct species

Several extinct species have been postulated, but owing to a lack of evidence they can only be regarded as hypothetical extinct species. They have caused confusion, as they may have been a separate species, a subspecies, or an introduced species.

Populations of several parrot species were described mainly in the unscientific writings of early travelers to the Caribbean and Mascarene Islands, and subsequently scientifically described by several naturalists mainly in the twentieth century, with no more evidence than the earlier observations and without specimens, to have their names associated with the extinct species that they were postulating.

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