Craniata, subphylum Craniata, subphylum Vertebrata, Vertebrata - fishes; amphibians; reptiles; birds; mammals

amphibian - cold-blooded vertebrate typically living on land but breeding in water; aquatic larvae undergo metamorphosis into adult form

genus Hynerpeton, Hynerpeton - earliest fossil amphibian ever found; of the Devonian; found in Pennsylvania

genus Ichthyostega - second earliest fossil amphibian ever found; of the Devonian; found in Greenland

Caudata, order Caudata, order Urodella, Urodella - salamanders; newts; congo snakes

Anura, Batrachia, order Anura, order Batrachia, order Salientia, Salientia - frogs, toads, tree toads

Gymnophiona, order Gymnophiona - an order of amphibians including caecilians

Labyrinthodonta, Labyrinthodontia, superorder Labyrinthodonta, superorder Labyrinthodontia - extinct amphibians typically resembling heavy-bodied salamanders or crocodiles and having a solid flattened skull and conical teeth; Devonian through Triassic

order Stegocephalia, Stegocephalia - in former classifications a division of Amphibia comprising all pre-Jurassic and some later extinct large salamandriform amphibia

polliwog, pollywog, tadpole - a larval frog or toad

class - (biology) a taxonomic group containing one or more orders