The
fossa ( or ; Malagasy ;
Cryptoprocta ferox) is a
cat-like, carnivorous
mammal endemic to
Madagascar. It is a member of the
Eupleridae, a
family of
carnivorans closely related to the
mongoose family (Herpestidae). Its
classification has been controversial because its physical traits resemble those of
cats, yet other traits suggest a close relationship with
viverrids (most
civets and their relatives). Its classification, along with that of the other Malagasy carnivores, influenced hypotheses about how many times mammalian carnivores have colonized Madagascar. With genetic studies demonstrating that the fossa and all other Malagasy carnivores are most closely related to each other (forming a
clade, recognized as the family Eupleridae), carnivorans are now thought to have colonized the island once around 18 to 20 million years ago.