It has a unique grey colored, crescent-shaped patch of bare skin covering its ears, a character not found in other curassows.

[5] The Alagoas curassow was first mentioned by German naturalist Georg Marcgrave in his work Historia Naturalis Brasiliae which was published in 1648.

Because of the lack of information and specimens, it was considered conspecific with the common razor-billed curassow, until 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, related to the crestless curassow, the other Mitu species with brown eumelanin in the tail tip.

Its lineage has been distinct since the Miocene-Pliocene boundary (approximately 5 million years ago), when it became isolated in refugia in the Atlantic Forest.

The captive population has been extensively hybridized with the razor-billed curassow,[10] and there are several dozen purebred birds left.

These are being maintained and bred in two privately owned professional aviaries in Brazil mainly due to lack of official interest owing to the long-standing doubt about the taxon's validity.

Although not much information is known about this species' interactions and behavior in the wild, the stomach contents of these birds were found to contain fruits specifically from the castelo tree.

For instance, the Chamek spider monkey also eats Clarisia racemosa, which could lead to competition with the Alagoas curassow.

Scientists have been controlling the sexual interactions within the species by pairing certain birds together in order to reduce hybridization and maintain the original Alagoas curassow.

[4] With the objective to preserve the species and to increase genetic variability in the population, the "original" stock had their DNA examined by scientists in order to guide future pairings.