Phlegethontioidea is a

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

of aistopod

tetrapodomorphs Tetrapodomorpha (also known as Choanata) is a clade of vertebrates consisting of tetrapods (four-limbed vertebrates) and their closest sarcopterygian relatives that are more closely related to living tetrapods than to living lungfish. Advanced for ...

s including the families Phlegethontiidae and Pseudophlegethontiidae. It is a

stem-based taxon Phylogenetic nomenclature is a method of nomenclature for taxon, taxa in biology that uses phylogenetics, phylogenetic definitions for taxon names as explained below. This contrasts with Biological classification, the traditional method, by which ...

defined in

phylogenetic In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical dat ...

terms as all aistopods sharing a more recent common ancestor with '' Phlegethontia'' than ''

Oestocephalus ''Oestocephalus'' is an extinct genus of Aïstopoda, aïstopod tetrapodomorphs that lived during the Carboniferous period. Fossils have been found in the Czech Republic, and in Ohio and Illinois in the United States. It is the type genus of the f ...

''.

References

Aistopoda Carboniferous first appearances Permian extinctions {{paleo-tetrapodomorph-stub