Table 3. Morphological traits of the new Amazona compared with other similarly red-fronted and -faced species of Amazona, including other species occurring in the Yucatán Peninsula (A. albifrons nana, A. xantholora, A. autumnalis).

Species	Average weight (grams)	Average length (cm)	Head coloration	Wing coloration	Tail coloration
New Amazona	200	25	Male: forehead and forecrown red; rear crown feathers subtle bluish tipped; periophthalmic ring red. Female: forehead red.	Underside of wings green, except tips of primaries which are bluish green.	Green, bluish tipped; three lateral tail feathers red on inner part.
A. albifrons nana	205 (range 198.1–213.0)	23	Male: forehead and forecrown white, posterior border blue; periophthalmic ring and lores red. Female: white on forehead and red of periophthalmic ring greatly reduced.	Primary coverts red in male, green or red greatly reduced in most females; primaries green, dark blue towards tip; secondaries blue; under-wing coverts green.	Green, yellowish-green towards tip; base of lateral feathers red.
A. a. albifrons	230 (range 207.4–244.4)	26	As A. a. nana, but green slightly darker.	As A. a. nana.	As A. a. nana.
A. a. saltuensis	230 (range 211.9–233.5)	26	As A. a. albifrons, but blue crown extends to nape.	As A. a. nana.	As A. a. nana.
A. xantholora	200 (range 197.1–238.2)	23	Male: forehead and forecrown white, posterior blue; lores yellow; periophthalmic ring red; ear coverts preeminently black. Female: all head colors significantly reduced, except for the crown, which is blue.	Primary and secondary flight feathers green, blue towards tip; underside of wings greenish-blue; red on shoulder present in some individuals, mainly males.	Tail green, yellowish-green towards edge; lateral tail feathers red at base.
A. autumnalis autumnalis	350 (range 338.9–369.0)	34	Forehead and upper part of lores red, lower part of lores and cheeks yellow, strongly hinted with red in some individuals from Mexico; crown blue	Primary and secondary flight feathers green, becoming dark blue towards tips; first five secondaries with red wing-speculum.	Green with greenish-yellow tips; outer webs of outer tail feathers blue.
A. viridigenalis	270 (range 266.4–299.2)	33	Forehead, upper lores and crown red; dark blue extends from rear part of eye and occiput to encircle cheeks, which are lighter green. Females have less red on head and some old males acquire several yellow feathers to the nape.	Outer webs of primaries violet-blue; secondaries with blue tips; first five secondaries with red wing-speculum.	Green, with green-yellow tips.

Notes.

Three individuals of each sex were measured for each taxon, except for Amazona autumnalis, in which six birds of unknown sex were taken into account.