The ounce may or may not be a wildcat native to Mexico. The cheetah is certainly a cryptid, an animal whose existence is doubtful and whose study corresponds to cryptozoologists.
The first descriptions of what the ounce could be come from the records of the Spanish conquerors.
The first descriptions of what the ounce might have been come from the accounts of the Spanish conquistadors who saw one in the huge zoo of Moctezuma, king of the Aztecs. Bernal Díaz del Castillo wrote in 1520 that among the carnivorous animals there were two species of lions, one of them with ears as long as those of a wolf. All American carnivores were new to the Spanish and used familiar animals as reference points. Shortly thereafter, in the trilingual compilation of Aztec lore called the Florentine Codex, a similar animal appears. The Aztecs called it cuitlamiztli, a Nahuatl word difficult to translate now. In the Codex it is called a “gluttonous cat” as it was said to eat all of its prey and then sleep for days. The translation “ring tail” suggests its patterned skin: “mitzli” itself referred to a cougar. When the Spanish occupied and colonized the ancient Aztec empire, they also saw the animal in the wild and called it the ounce.
An ounce can be similar to a hyena.
The shortage of ounce bills makes sense; if an animal is a fixture in its environment, its name is sufficient as a description, and there is no need to write about its characteristics in detail. During the 18th century, new European missionaries in Sonora, a Mexican state far north of the old Aztec Empire, noted the alarming presence of this large and particularly dangerous creature, but described its appearance as only a puma.
An Onza is a mythical cat-like creature that lives in Mexico.
In 1938, a group of men hunting in the state of Sinaloa, near Sonora, shot dead an unusual-looking feline that locals identified as an ounce; those who saw him said that his ears were noticeably longer than those of a cougar and that his build was slimmer. Another strange cat killed in 1986 provided the most useful evidence about the nature of the cheetah. A peasant who showed the body reported that his father had shot the same type of animal, and that it was an ounce. This one was photographed: it looks like a very skinny, long-legged cougar. A zoologist who examined the body also did DNA tests and concluded that, although it was slimmer and had retractable claws, the cat was not genetically different from a cougar. This put an end to the notion that the cheetah could be a living relic of the prehistoric American cheetah.
The cheetah, then, may be a recurring variant of the cougar. Alternatively, the skinny cat killed in 1987 may not be the historical ounce or cuitlamittli, but a different animal entirely. Ounce, from the Latin for “leopard,” is a flexible word when it comes to cats. The jaguarondi, a small, non-aggressive bobcat, is called the ounce in some areas of its habitat. Onca, the Portuguese variant of ounce, is the Brazilian word for leopard. The word is also related to “lynx” and an obsolete English word for leopard, “jaguar”.
Castillo’s description is brief and vague, part of a long catalog of wonders found in the amazing Moctezuma Zoo. Instead of looking at some kind of cat, he may have seen some kind of dog, maybe even something like a hyena. This last possibility introduces another extinct species into the breed: Chasmaportethes ossifragus, the only relative of the hyena in North America, an animal from the Pleistocene. It is not at all likely that this is what Castillo saw as a wolf-lion, but it is possible. It is also possible that the Onza of the Spanish and the Cuitlamitztli of the Aztecs, whether they are from the same animal or not, are extinct.