Crossopterygii

plural noun

Cros·​sop·​te·​ryg·​ii
1
: a superorder of Choanichthyes comprising the lobe-finned fishes that have existed since the Devonian but are now largely extinct, that have paired fins somewhat resembling limbs with a scaly axis fringed on one or both sides by dermal rays, and that are generalized fishes in some respects resembling elasmobranchs and in others foreshadowing terrestrial vertebrates which may have evolved from unknown early members of the group compare latimeria
2
in some classifications : a division of fishes coextensive with Choanichthyes or comprising Choanichthyes together with Cladistia compare actinistia , rhipidistia

Word History

Etymology

New Latin, from cross- + -pterygii

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Cite this Entry

“Crossopterygii.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Crossopterygii. Accessed 25 Mar. 2023.

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