Balaenoptera bertae is an extinct species of baleen whale that lived from 3.35 to 2.5 Mya during the Pliocene[1] in the region of today's San Francisco Bay Area. Il held, also during the early to middle Neogene, a diverse assembly of cetaceans. Their fossilized remains were found in the Purisima Formation.[2] The species Balaenoptera bertae was discovered in 2013.
Balaenoptera bertae is estimated to be 5mto6mm (16feetto20feetm).[3] It is slightly smaller than the modern minke whale. It is known from a partial skull which is missing a maxilla, premaxillae and nasals.[4]