In 2000 and 2006, paleontologists led by Octávio Mateus described a find from the Lourinhã Formation in central-west Portugal (ML 352) as a new specimen of "Ceratosaurus", consisting of a right femur (upper thigh bone), a left tibia (shin bone), and several isolated teeth recovered from the cliffs of Valmitão beach, between the municipalities Lourinhã and Torres Vedras. The bones were found embedded in yellow to brown, fine-grained sandstones, which were deposited by rivers as floodplain deposits and belong to the lower levels of the Porto Novo Member, which is thought to be late Kimmeridgian in age. Additional bones of this individual (SHN (JJS)-65), including a left femur, a right tibia, and a partial left fibula (calf bone), were since exposed due to progressing cliff erosion. Although initially part of a private collection, these additional elements became officially curated after the private collection was donated to the Sociedade de História Natural in Torres Vedras, and were described in detail in 2015. The specimen was ascribed to the species "Ceratosaurus dentisulcatus" by Mateus and colleagues in 2006. A 2008 review by Carrano and Sampson confirmed the assignment to "Ceratosaurus", but concluded that the assignment to any specific species is not possible at present. In 2015, Elisabete Malafaia and colleagues, who questioned the validity of "C. dentisulcatus", assigned the specimen to "Ceratosaurus" aff. "Ceratosaurus nasicornis".