California discovery of 40-million-year-old rare fossils

Rare 40-to-45-million-year-old animal fossils have been discovered during municipal infrastructure work in Oceanside, California. The remains, including ribs, leg bones, and thigh bones, were found approximately 12 feet underground within the 'Member C' section of the San Diego Rock Formation.

Lead paleobiologist Dr. Joseph L. Athly suggests the fossils may belong to a 'Perissodactyla' mammal from the Eocene epoch. Researchers believe the specimen could be a massive, rhino-sized 'Brontothere' characterized by a Y-shaped horn on its nose, or potentially an hornless, water-dwelling 'Amynodont' known as a 'swamp rhino'.

The recovered bones were carefully extracted using plaster casts to prevent damage and have been transported to a laboratory for cleaning and reinforcement using specialized chemicals.