A University of Otago spokeswoman said the bones from Llanocetus denticrenatus where discovered on Seymour Island, off the east coast of the Antarctic Peninsula, by Emeritus Prof Ewan Fordyce in 1987.
"Part of a jaw with teeth was found by American researchers in the mid-1970s on Seymour Island.
"As a New Zealand fossil whale researcher, Ewan was invited to join an expedition to Seymour Island a decade later, and found the site and much of the rest of the specimen now exposed.
"He excavated it with the expedition team, and it was shipped back to New Zealand for preparation and study."
It is the second-oldest baleen whale known and represents a major piece in the evolutionary jigsaw of early whales.
The university’s geology department signed a deed of gift with the Smithsonian earlier this year, and the skull and partial skeleton of Llanocetus denticrenatus would be shipped to the Smithsonian in mid-2023, so they could be reunited with the original jaw fragment, the holotype material of Llanocetus.
"It is a great opportunity to unify Llanocetus, and continue our friendships and research relationships with other significant fossil whale collections around the world," she said.
