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Related to Synapsida: Diapsids
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.Synapsida - extinct reptiles of the Permian to Jurassic considered ancestral to mammals
class Reptilia, Reptilia - class of cold-blooded air-breathing vertebrates with completely ossified skeleton and a body usually covered with scales or horny plates; once the dominant land animals
order Therapsida, Therapsida - extinct mammal-like reptiles found inhabiting all continents from the mid Permian to late Triassic
Ictodosauria, order Ictodosauria - extinct reptiles of the later Triassic period
order Pelycosauria, Pelycosauria - edaphosaurus; dimetrodon
class - (biology) a taxonomic group containing one or more orders
References in periodicals archive ?
Synapsida includes a number of extinct lineages that dominated the communities on land in the Late Permian (260-252 million years ago), as well as living mammals and their direct ancestors.