Definition of Sarcopterygii
: a subclass or other division of bony fishes (such as the coelacanth) that have paired, lobed, fleshy fins somewhat resembling limbs, that may be ancestral to the terrestrial vertebrates, and that have existed since the Devonian but are now largely extinct — compare actinopterygii
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1962
First Known Use of sarcopterygii
1962
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