Mystacodon is a genus of toothed baleen whale from the Late Eocene Yumaque Member of Paracas Formation (previously called as Yumaque Formation) of the Pisco Basin in southwestern Peru. It is the oldest known baleen whale, and was probably a suction feeder of small prey on the seafloor.
Mystacodon is a genus of toothed baleen whale from the Late Eocene Yumaque Member of Paracas Formation (previously called as Yumaque Formation) of the Pisco Basin in southwestern Peru. It is the oldest known baleen whale, and was probably a suction feeder of small prey on the seafloor.
== Taxonomy == Mystacodon is the oldest known baleen whale, the holotype specimen dating to 36.4 million year ago to the Priabonian of the latest Eocene. The holotype, MUSM 1917, comprises the braincase, teeth, the spinal cord excluding the sacral vertebrae, some fin bones, and the left hip bone. It was originally classified into its own family, Mystacodontidae, but it was moved to the family Llanocetidae in 2018 alongside Llanocetus–the second-oldest baleen whale–and an undescribed New Zealand specimen OU GS10897.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).