The last diadectomorph sheds light on Late Palaeozoic tetrapod biogeography

Diadectomorpha is a clade of Late Palaeozoic vertebrates widely recognized as the sister group of crown-group Amniota and the first tetrapod lineage to evolve high-fibre herbivory. Despite their evolutionary importance, diadectomorphs are restricted stratigraphically and geographically, with all records being from the Upper Carboniferous and Lower Permian of North America and Germany. We describe a new diadectomorph, Alveusdectes fenestralis,...