Thylacosmiliformes

Thylacosmiliformes
Temporal range:
Middle MioceneLate Pliocene,
Skull of Thylacosmilus
Lower jaw of Anachlysictis
Scientific classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Sparassodonta
Superfamily: Borhyaenoidea
Clade: Thylacosmiliformes
Suarez et al., 2025
Type species
Thylacosmilus atrox
Riggs, 1933
Subgroups

Thylacosmiliformes is an extinct clade of predatory metatherian mammals in the order Sparassodonta, related to the marsupials. Members of this clade are known from the Miocene and Pliocene epochs of South America (Argentina, Colombia, and Uruguay). The most notable thylacosmiliforms, such as Thylacosmilus, comprise the more exclusive family Thylacosmilidae and have prominent saber teeth.

The clade was defined in 2025 to include thylacosmilids and their more "primitive" closest relatives such as Dimartinia.