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Related to protomammal: Mammal-like reptiles
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.protomammal - probably warm-blooded; considered direct ancestor of mammals
synapsid, synapsid reptile - extinct reptile having a single pair of lateral temporal openings in the skull
order Therapsida, Therapsida - extinct mammal-like reptiles found inhabiting all continents from the mid Permian to late Triassic
Chronoperates paradoxus - shrew-sized protomammal from the Alberta region of Canada; from about 55 million years ago (much more recent than other mammal-like reptiles)
cynodont - small carnivorous reptiles
dicynodont - a kind of therapsid