chalchihuitzilin.

CHALCHI-HUĪTZIL-IN, literally, “jade hummingbird,” perhaps the Mexican Violetear (Colibri mexicanus) [FC: 24 Chalchihujtzili] “… is light green; a turquoise shade; herb-green." Martin del Campo identified this as the Broad-billed Hummingbird (Cynanthus latirostris), a quite reasonable option; however, I believe that species is more likely named XI-HUĪTZITZIL-IN. See HUĪTZIL-IN hummingbird.
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analysis here also appearing in E. S. Hunn, "The Aztec Fascination with Birds: Deciphering Sixteenth-Century Sources," unpublished manuscript, 2022, cited here with permission.