The Lissamphibia (Greek λισσός, lissos, "smooth" + ἀμφí, amphi, "both" + βíος, bios, "life") are a subclass of animals that includes all recent amphibians. For several decades, this name has been used for a group that includes all extant amphibians, but excludes all the main groups of Paleozoic tetrapods, such as TemnospondyliLepospondyliEmbolomeri, and 


Seymouriamorpha.[1] Some authors hold that Lissamphibia is a clade, that the subclass consists of all the descendants of an ancestral lissamphibian, but others[2] hold that frogs and salamanders derive from temnospondyls, whereas caecilians derive from lepospondyls, so Lissamphibia is polyphyletic.

Living amphibians fall into one of three orders: the Anura (frogs and toads), the Caudata or Urodela (salamanders and newts), and the Gymnophiona or Apoda (the limbless caecilians). An extinct group, the family Albanerpetontidae in the order Allocaudata, was moderately successful, spanning 160 million years from the Middle Jurassic to the Early Pliocene, an interval that ended 3.6 million years ago.

Some writers have argued that the Early Permian dissorophoid Gerobatrachus hottoni is a lissamphibian.[2] If it is not,[3] the earliest known lissamphibians are Triadobatrachus and Czatkobatrachus from the Early Triassic.