necuilictli.

NECUILIC-TLI/NECUILOC-TLI/ECA-CHICH-INQUI/CENOTZ-QUI/TLETLEUH-TON, Merlin (Falco columbarius) [FC: 45 Necujlictli] “—or necuiloctli, or ecachichinqui; and they name it cenotzqui and tletleuhton. It is of average size. The bill is pointed, small and pointed. It is an eater of mice, of lizards, of çacacilin [zacacilin birds]. It is an air-sucker. It is [spotted] yellow and black. When it has eaten, when it sucks in air; it is said that thus it gets water. And from the wind it knows when the frost is about to come. Then it begins to sing.” A rather puzzling profusion of names and a somewhat obscure description. It is listed in the Codex between the falcons and the shrike, suggesting that it is a species of raptor, most likely the Merlin. It is a winter visitor throughout Mexico. This might explain the reference to its singing at the onset of frosts. See also ITZ-TLOH-TLI.
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); 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analysis here also appearing in E. S. Hunn, "The Aztec Fascination with Birds: Deciphering Sixteenth-Century Sources," unpublished manuscript, 2022, cited here with permission.

See the Florentine Codex for a painting of this bird:
Available at Digital Florentine Codex/Códice Florentino Digital, edited by Kim N. Richter and Alicia Maria Houtrouw, "Book 11: Earthly Things", fol. 49r, Getty Research Institute, 2023. https://florentinecodex.getty.edu/en/book/11/folio/49r/images/ce983b42-2... Accessed 18 October 2025.