yacapatlahuac.

YACA-PATLA-HUAC, literally, “has a flat nose,” Northern Shoveler (Spatula clypeata) [FC: 38 Iacapatlaoac] “It is a duck. It is named yacapatlauac because its bill is somewhat long and very wide at the end. It is the size of a goose…. It molts [here] twice…. Its head is a very resplendent black as far as its shoulders. Its eyes are yellow, its breast whitish, it back ashen…. Its wings are silvery; its flight feathers green, glistening, black at the ends…. Its belly shows tawny; its legs are chili-red. Also it does not rear its young here; it also migrates…. Many come here.” I agree with Martin del Campo that this is an excellent description of the Northern Shoveler.
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analysis here also appearing in E. S. Hunn, "The Aztec Fascination with Birds: Deciphering Sixteenth-Century Sources," unpublished manuscript, 2022, cited here with permission.