tzitzihua.

TZITZIHUA, Northern Pintail (Anas acuta) [FC: 36 Tzitzioa] “It is a duck. It is named tzitziua because of the feathers growing from its rump; among its tail feathers are two very white ones,… a third,… stands between them. Their points are curved; they turn upward…. It does not rear its young here; it also migrates. Neither does it come singly; there are many.” I agree with Martin del Campo that this is the Northern Pintail. See also CANAUH-TLI “duck.”
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analysis here also appearing in E. S. Hunn, "The Aztec Fascination with Birds: Deciphering Sixteenth-Century Sources," unpublished manuscript, 2022, cited here with permission.

The Florentine Codex includes a painting of this bird in Book 11, folio 37r.
Available at Digital Florentine Codex/Códice Florentino Digital, edited by Kim N. Richter and Alicia Maria Houtrouw, "Book 11: Earthly Things", fol. 37r, Getty Research Institute, 2023. https://florentinecodex.getty.edu/en/book/11/folio/37r/images/0 Accessed 17 October 2025.