Diadectomorpha

Diadectomorphs Temporal range: Late Carboniferous–Wuchiapingian PreꞒ Ꞓ O S D C P T J K Pg N [1]
Skeleton of Diadectes sideropelicus in the American Museum of Natural History
Skeleton of Limnoscelis paludis
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Reptiliomorpha
Order:	†Diadectomorpha Watson, 1917
Subgroups
See text.

Diadectomorpha is a clade of large tetrapods that lived in Euramerica during the Carboniferous and Early Permian periods and in Asia during Late Permian (Wuchiapingian),^[1] They have typically been classified as advanced reptiliomorphs (transitional between "amphibians" sensu lato and amniotes) positioned close to, but outside of the clade Amniota, though some recent research has recovered them as the sister group to the traditional Synapsida within Amniota, based on inner ear anatomy and cladistic analyses.^[2][3][4][5] They include both large (up to 2 meters long) carnivorous and even larger (to 3 meters) herbivorous forms, some semi-aquatic and others fully terrestrial. The diadectomorphs seem to have originated during late Mississippian times, although they only became common after the Carboniferous rainforest collapse and flourished during the Late Pennsylvanian and Early Permian periods.