Rapa Nui Parrot (Psittacidae gen. & sp.)
“Parrots are represented by a partial quadrate of a very large species (larger than in Nestor, Prosopeia, Eclectus, or any lorikeet; dissimilar from that in neotropical parrots) and digit I, phalanx 2 of the wing (larger than in Vini or Cyanoramphus, smaller than in Nestor or Eclectus; ca. the size in Prosopeia).” [1]
It is usually thought that the island formerly was inhabited by two species of parrots, however, I personally think that this might well have been a single one, a large parrot with very reduced wings.
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References:
[1] David W. Steadman: Extinction and Biogeography of Tropical Pacific Birds. University of Chicago Press 2006
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edited: 22.06.2020