Protorosaurus

Protorosaurus ("first lizard") is a genus of lizard-like early archosauromorph reptiles. Members of the genus lived during the late Permian period in Germany and Brazil. Once believed to have been an ancestor to lizards, Protorosaurus is now known to be one of the oldest members of the lineage that would eventually lead to archosaurs such as crocodilians and dinosaurs.

Protorosaurus Temporal range: Lopingian ~260–251 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Fossil specimen, Teyler's Museum
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Clade:	Archosauromorpha
Genus:	†Protorosaurus von Meyer 1830
Species:	†P. speneri
Binomial name
†Protorosaurus speneri von Meyer 1830

Description

Life restoration

Protorosaurus grew up to 2 metres (6.6 ft) in length, and was a slender, lizard-like animal, with long legs and a long neck. Its body form suggests that it was fast-moving, although it may have fed primarily on insects.[1] Protorosaurus was closely related to Czatkowiella from the Early Triassic of Poland.[2]

Discovery

In 1914, a new ceratopsian dinosaur found by Lawrence Lambe was again given the name Protorosaurus (in this sense meaning "before Torosaurus"). When Lambe found that the name had already been used for the early archosauromorph, he renamed his ceratopsian Chasmosaurus.

In Geopark of Paleorrota, Rio Grande do Sul, Brazil, 3 vertebrae and some bones of the animal were found.

Relationships

Skeleton illustration

The cladogram below follows an analysis by Ezcurra (2016), and highlights the position of Protorosaurus among other early archosauromorph reptiles.[3]

Archosauromorpha	†Aenigmastropheus       †Protorosaurus       †Tanystropheidae    Crocopoda    †Allokotosauria       †Rhynchosauria       †Boreopricea       †Prolacertidae       †Tasmaniosaurus     Archosauriformes

References

1. Palmer, D., ed. (1999). The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals. London: Marshall Editions. p. 93. ISBN 1-84028-152-9.
2. Borsuk–Białynicka, M.; Evans, S.E. (2009). "A long–necked archosauromorph from the Early Triassic of Poland" (pdf). Palaeontologia Polonica. 65: 203–234.
3. Ezcurra MD. (2016) The phylogenetic relationships of basal archosauromorphs, with an emphasis on the systematics of proterosuchian archosauriforms. PeerJ, 4:e1778