The Alagoas Curassow, Mitu mitu, is a large, up to 89 cm long, pheasant-like bird with a whitish-tipped red bill, black glossed purplish blue plumage, chestnut under-belly, reddish brown iris and fourteen pale brown-tipped tail feathers. It has a unique bare greyish crescent-shaped ear patch not found in other curassows. The female is slightly lighter than the male. Its diet consists mainly of fruits. They can reach an age of more than 24 years in captivity.

The rare Alagoas Curassow was first mentioned by German naturalist Georg Marcgraf in his work Historia Naturalis Brasiliae which was published in 1648. Because of lack of information and specimen, it was considered the same species with the Razor-billed Curassow, until after its rediscovery in 1951 in the Alagoas lowland forests, Brazil. Following the review of Pereira & Baker (2004), they are today believed to be a fairly basal lineage of its genus and closer to the Crestless Curassow, the other Mitu species with brown eumelanin in the tail tips. Its lineage is distinct since the Miocene-Pliocene boundary (little more than 5 million years ago), when it became isolated in the Mata Atlântica refugium (Pereira & Baker 2004).

Due to ongoing habitat loss, overhunting and very small population size, the Alagoas Curassow is evaluated as Extinct in the Wild on the IUCN Red List of Threatened Species. The last wild Alagoas Curassow was seen and killed in 1984, and possibly 1987 or 1988. The captive population has been extensively hybridized with the Razor-billed Curassow, and there are a few dozen purebred birds left. These are being maintained and bred in two privately-owned professional aviaries mainly due to lack of official interest owing to the long-standing doubt about the taxon's validity.

The Alagoas Curassow is protected under Brazilian law and is listed on Appendix I of CITES.