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Basilosaurinae

Basilosaurinae is a subfamily of cetaceans archaeocetes containing two genera: Basilosaurus and Basiloterus. They were characterized by elongated distal thoracic vertebrae, lumbar, and proximal sacrococcygeal. All known members of the subfamily are larger than their relatives of the Dorudontinae subfamily except Cynthiacetus.

It was declared an invalid subgroup of Basilosauridae by .