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Related to pelycosaur: therapsid, edaphosaurus


Any of various extinct, chiefly carnivorous synapsids of the Carboniferous and Permian Periods, including the dimetrodon and other species with saillike structures along the back.

[New Latin Pelycosauria, name of the former suborder in which the various pelycosaurs were classified : Greek pelux, peluk-, bowl, cup (from the typical shape of the ischium ) + Greek sauros, lizard.]


(Palaeontology) any extinct mammal-like reptile of the order Pelycosauria, of Upper Carboniferous to Lower Permian times, from which the therapsids are thought to have evolved
[C19: from New Latin Pelycosauria, from Greek pelyx bowl, pelvis, + -saur]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.pelycosaur - large primitive reptile having a tall spinal sail; of the Permian or late Paleozoic in Europe and North America
synapsid, synapsid reptile - extinct reptile having a single pair of lateral temporal openings in the skull
order Pelycosauria, Pelycosauria - edaphosaurus; dimetrodon
References in periodicals archive ?
3) A metatarsal possibly of Trichasaurus, a caseid pelycosaur from the Leonardian of Texas.
Also skipping the sand dunes was Pelycosaur Ophiacodon, a flesh-eating reptile-cum-mammal, again only found in this county.
Romer and Price (1940) described such ridges in both Ophiacodon, a primitive pelycosaur, and Dimetrodon, a more advanced form, and presume they were probably present in other forms as well.