The Yucatan jay (Cyanocorax yucatanicus) is a species of bird in the family Corvidae, the crows and their allies.

It is native to the Yucatán Peninsula where its habitats are subtropical or tropical dry forest, plantations and cleared areas at altitudes up to 250 m (820 ft).

[3][4] In 1934, ornithologist Carl Eduard Hellmayr reorganized the genus Cyanocorax and split it into four subgenera.

[7] This relationship was confirmed by a 2010 mitochondrial DNA study, which showed that these four species were closely related.

[8] The following cladogram (simplified from the 2010 study) shows the relationship between species in the genus Cyanocorax.

Juvenile Yucatan jays have a white head, body, and tail tip.

The prebasic moult also begins at this point, with the white head and body feathers being replaced with black ones.

The back and tail turn a deeper grey, and the retrices are tipped with white.

In June or August, the bill may start to develop dark patches, while remaining overall yellow.

The eye ring is still distinctive of age, with some black marks appearing on the otherwise yellow flesh.

In the fourth year and later, the Yucatan jay has reached its full adult plumage.

[18][10] The Yucatan jay is found primarily in the Yucatán Peninsula, which comprises the northern part of the nation of Belize; Guatemala's northern El Petén Department; and the Mexican states of Yucatán, Quintana Roo, and Campeche.