huexocanauhtli.

HUEXŌ-CANAUH-TLI, literally, “willow duck,” Green Heron (Butorides virescens) [FC: 27 Vexocanauhtli] “Its legs are long, dark green. Its bill is pointed, long and pointed, green…. The head becomes chili-red; its legs become long, rope-like. Its legs are stringy.” Martin del Campo identified this as the Black-crowned Night-Heron, despite the fact that he also identified Oactli as this heron. The description here does not fit. I suspect this is the Green Heron. Though labeled a “duck,” that term is applied more liberally by the Aztec scribes, to include the Black-crowned Night-Heron and even the Belted Kingfisher, so the Green Heron might also be a “duck,” that is, CANAUH-TLI. See also HUAC-TLI “Black-crowned Night-Heron.
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analysis here also appearing in E. S. Hunn, "The Aztec Fascination with Birds: Deciphering Sixteenth-Century Sources," unpublished manuscript, 2022, cited here with permission.