It is about twice as large as a domestic cat (Felis catus), reaching nearly 360 mm (14 in) at the shoulder, and weighs 3.5–7 kg (7.7–15.4 lb).

Secretive and alert, the jaguarundi is typically solitary or forms pairs in the wild, though captive individuals are more gregarious.

Unlike other sympatric cats such as the ocelot, the jaguarundi is more active during the day and hunts mainly during daytime and evening hours.

The jaguarundi inhabits a broad array of both closed and open habitats ranging from tropical rainforests and deciduous forests to deserts and thorn scrubs.

[7][8] In 1803 Étienne Geoffroy Saint-Hilaire described two jaguarundi skins and skulls from unknown locations in Central America and proposed the scientific name Felis yagouarundi.

[19] In 2017, the IUCN Cat Specialist Group revised felid taxonomy and recognises the jaguarundi as a monotypic taxon of the genus Herpailurus.

The sister group of the Puma lineage is a clade of smaller Old World cats that includes the genera Felis, Otocolobus and Prionailurus.

This was possibly followed by the bifurcation of the lineage into the cougar and Herpailurus (represented by H. pumoides) in South America around 4 to 3 million years ago between the Late Pliocene and Early Pleistocene.

[30] The coat is uniformly colored with at most a few faint markings on the face and the belly, though kittens are spotted for a short duration.

[34][38] Blackish brown individuals superficially resemble the tayra (Eira barbara), but the latter can be told apart by the clear, yellowish patch on the throat.

Melanistic individuals have been reported, but the coat is not completely black; the head and the throat are clearly paler than the rest of the body.

[40] The jaguarundi inhabits a wide variety of habitats, from tropical rainforests and deciduous forests to deserts and thorn scrubs.

[42] It is possibly extirpated in the United States;[1] a 1999 study refuted claims of sightings in Arizona, in the Huachuca Mountains in Santa Cruz County.

Their presence there is attributed to a writer from Chiefland who at some point imported the animals from their native habitat and released them near his hometown and in other locations across the state.

[35] Though activity has been observed throughout the day and at night, jaguarundis seem to prefer hunting during daytime and evening hours; for instance, a study in Belize reported that jaguarundis started moving before dawn and remained active through most of the day till sunset with a peak in hunting from late morning to noon.

[35] Jaguarundis are efficient climbers as well, but hunt mainly on ground; the coat color works as a good camouflage for terrestrial activity.

[30][48] Marking behavior could serve as a means of olfactory or visual communication among jaguarundis; individuals in captivity have been observed scraping areas with their hind feet (sometimes with urination), clawing on logs, rubbing objects with their heads and leaving feces uncovered.

In captivity, females in estrus have been observed making faint sounds as they scent mark the area around their enclosures.

[34][10] The jaguarundi typically feeds on small-sized prey weighing less than 1 kg (2.2 lb), including ground-feeding birds, reptiles, frogs, arthropods, rodents and small mammals.

[49] Jaguarundis will also take larger prey such as domestic poultry, fish, marmosets, rabbits and opossums; a study recorded small deer (possibly carrion) in the diet.

In particular, rodents of the genus Oryzomys, Sigmodon and Zygodontomys were found to be the most targeted prey items in several range countries.

[34][10] After a gestation period of 70 to 75 days, a litter of one to four kittens is born in a den constructed in a dense thicket, hollow tree, or similar cover.

The huge protected areas in the Amazon Basin are probably the only conservation units that can sustain long-term viable populations.

[52] Hunting jaguarundi is restricted in Peru and banned in Argentina, Belize, Brazil, Bolivia, Colombia, Costa Rica, French Guiana, Guatemala, Honduras, Mexico, Panama, Paraguay, Suriname, Uruguay, United States, and Venezuela.