xiuhquecholli.

XIUH-QUECHŌL/XIUH-QUECHŌL-LI, Lesson’s Motmot (Momota lessonii) [FC: 20 Xiuhquechol] “Its feathers are herb-green; its wings and tail are blue. It lives in Anahuac.” Martin del Campo identified this as the Lesson’s Motmot. A recent taxonomic split raises the possibility that this might also include the Blue-capped Motmot (Momotus coeruliceps). Though the description is brief, this is a reasonable interpretation. I’m uncertain as to the extent of “Anahuac,” so can’t determine the range more clearly. These two motmot species are common on the Atlantic slope.
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 11 – Earthly Things, no. 14, Part XII, eds. and transl. Arthur J. O. Anderson and Charles E. Dibble (Santa Fe and Salt Lake City: School of American Research and the University of Utah, 1963); Rafael Martín del Campo, “Ensayo de interpretación del Libro Undecimo de la Historia General de las Cosas de Nueva España de Fray Bernardino de Sahagún – 11 Las Aves (1),” Anales del Instituto de Biología Tomo XI, Núm. 1 (México, D.F., 1940); and, with quotation selections, synthesis, and analysis here also appearing in E. S. Hunn, "The Aztec Fascination with Birds: Deciphering Sixteenth-Century Sources," unpublished manuscript, 2022, cited here with permission.

xiuhquecholli = cotinga bird (momotus lessoni goldmani)
Kay A. Read and Jane Rosenthal, "The Chalcan Woman's Song: Sex as a Political Metaphor in Fifteenth-Century Mexico," The Americas 62:3 (January 2006), 313–348, see page 323, note 49.

a ca xiuhquechol tzinitzcan tlauhquechol oncan oncuica tlahtoa ya = There! The turquoise swan, the trogon, the roseate swan is singing, warbling, happy with these flowers. (ca. 1582, central Mexico) John Bierhorst, Ballads of the Lords of New Spain (Austin: University of Texas Press, UTDigital, 2009), f. 3r.; http://utdi.org/book/index.php?page=songs.php