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When did pycnodontiform fishes live?
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holostean
Living and fossil forms of Holostei.
The Pycnodontiformes were an order of extinct fishes that lived from the Late Triassic to the Eocene, a span of approximately 228.7 million to 33.9 million years ago. While they are often associated with the holostean group, their exact evolutionary placement remains a subject of scientific debate.123