The Réunion solitaire or the white dodo is an unknown extinct bird in the Raphinae genus. It was described as being very similar to a dodo, which was not native to Réunion but had some morphological differences, namely its white plumage, yellow wings and black wingtips, and more slender feet.
The Réunion solitaire was first reported in 1613 by J. Tatton, who described seeing “large white fowl” on Réunion. In 1638, Hamon L’Estrange saw a light-coloured dodo on exhibit in London. Interestingly, after the dodo's extinction, French explorers Carré and Du Bois in 1668/1669 reported turkey-sized “white dodos” on Réunion that they referred to as solitaires. Between 1735 and 1746, French naval officer Bertrand-François Mahé de La Bourdonnais allegedly sent a Réunion Solitaire back to France, although whatever happened to it is unknown.
The most common theory as to the Reunion solitaire’s origin is that it was vague, conflated reports of the Réunion ibis, a species that lived on Réunion until the 1700s that was never scientifically described when it was extant. Unlike the solitaire, however, the Réunion ibis had a much slimmer body and longer beak. It's unknown if the Réunion ibis had white plumage and yellow wings, so the theory remains speculative, although generally accepted.
Peter Holsteyn II's painting of a Réunion solitaire (c. 1650)
a modern reconstruction of a Réunion Ibis based on skeletal remains