Desmostylia
Extinct order of mammals
Desmostylia (from Ancient Greek δεσμά (desmá), meaning "bundle", and στῦλος (stûlos), meaning "pillar") is an extinct order of aquatic mammals native to the North Pacific from the Early Oligocene (Rupelian) to the Late Miocene (Tortonian) from 33.9 to 7.2 or 5.3 Ma. However, phylogenetic models suggests the order first appeared during Middle Eocene between 47 and 39 Ma. Desmostylians are the only known extinct order of marine mammals.
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