Mesosauria

plural noun
Meso·​sau·​ria

Definition of Mesosauria

: an order of primitive aquatic and probably web-footed reptiles from the Permian of South America and Africa that are distinguished by an elongate head with the nostrils near the eyes and are sometimes included in Pelycosauria as a suborder

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History and Etymology for Mesosauria

New Latin, from mes- + -sauria

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