Their closest relatives are thought to be the Calyptocephalellidae of southern South America, from which they diverged during the mid-Cretaceous (about 100 million years ago). Together, they comprise the clade Australobatrachia; their common ancestor is thought to have inhabited South America, with the ancestors of Myobatrachoidea dispersing to Australasia during the Cretaceous via (then ice-free) Antarctica.[2] Both families within Myobatrachoidea are thought to have diverged from each other during the Late Cretaceous or during the earliest Paleocene (immediately after the Cretaceous-Paleogene extinction event).[3]
Taxonomy
Myobatrachoidea contains the following families:[1]