The jay (''Aphelocoma ultramarina'') is a bird
endemic
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...
to Mexico.
Description
It is a medium-large (~120 g)
passerine bird
A passerine () is any bird of the order Passeriformes (; from Latin 'sparrow' and '-shaped'), which includes more than half of all bird species. Sometimes known as perching birds, passerines are distinguished from other orders of birds by ...
similar in size to most other
jays, with a blue head, blue-gray mantle, blue wings and tail, gray breast and underparts. The sexes are morphologically similar, and juveniles differ only in having less blue coloration. The iris is brown and legs are black. It is most readily distinguished by the plain (unstreaked) throat and breast, and the mantle contrasting less with the head and wings.
Systematics
A 2011 decision by the American Ornithologists' Union Check-list Committee treats some populations of the
Mexican jay
The Mexican jay (''Aphelocoma wollweberi'')
Etymology: ''Aphelocoma'', from Latinized Ancient Greek ''apheles-'' (from ἀφελής-) "simple" + Latin ''coma'' (from Greek ''kome'' κόμη) "hair", in reference to the lack of striped or banded ...
as a separate species, called the Transvolcanic jay (''A. ultramarina''), based on diagnosable phenotypic differences in plumage and morphology, millions of years of genetic divergence, and no evidence for interbreeding with Mexican Jays. The Transvolcanic jay inhabits montane forest in the
Transvolcanic Belt of central Mexico. Populations to the north retained the common name Mexican jay, but their Latin name changed to ''A. wollweberi'' because the Transvolcanic jay is the original ''A. ultramarina''.
Footnotes
References
*Chesser, R. Terry, Richard C. Banks, F. Keith Barker, Carla Cicero, Jon L. Dunn, Andrew W. Kratter, Irby J. Lovette, Pamela C. Rasmussen, J. V. Remsen, James D. Rising, Douglas F. Stotz, Kevin Winker. 2011. Fifty-second supplement to the American Ornithologists' Union Check-List of North American Birds. Auk 128(3):600-613.
{{Taxonbar, from=Q4876403
Aphelocoma
Jays
Birds of Mexico
Birds described in 1825
Taxa named by Charles Lucien Bonaparte
Birds of the Sierra Madre Occidental
Birds of the Trans-Mexican Volcanic Belt