Llanocetidae is an extinct

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

of ancient toothed

baleen whale Baleen whales ( systematic name Mysticeti), also known as whalebone whales, are a parvorder of carnivorous marine mammals of the infraorder Cetacea ( whales, dolphins and porpoises) which use keratinaceous baleen plates (or "whalebone") in th ...

s from the

Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...

. It was named by American paleontologist Edward Mitchell in 1989 after describing the Antarctic ''

Llanocetus ''Llanocetus'' ( "Llano's whale" ) is a genus of extinct toothed baleen whales from the Late Eocene of Antarctica. The type species, ''Llanocetus denticrenatus'', reached gigantic proportions, with the juvenile specimen reaching an estimated in ...

'', but a 2018 study by paleontologists

Ewan Fordyce Ewan is an anglicisation of the Scottish Gaelic name Eòghann. It is possibly a derivative of the Pictish name, ''Vuen'' (or 'Wen'), "The Warrior" or "born of the mountain". It is most common as a male given name in Scotland and Canada. It is ...

and Felix Marx included the Peruvian '' Mystacodon'' and an undescribed New Zealand specimen OU GS10897.

References

Baleen whales Eocene cetaceans Fossil taxa described in 1989 {{Paleo-whale-stub