Sphodrosaurus

Sphodrosaurus^[1][2] is an extinct genus of basal archosauriform reptiles from the Late Triassic-aged New Oxford Formation (not the Brunswick Formation as initially suggested) of Pennsylvania. The type species is S. pennsylvanicus, described by Edwin Colbert in 1960.^[3] The holotype (NMN, Franklin and Marshall College 2321; the cast is listed under AMNH 7601) consists of a partial skeleton including the back of the skull, the vertebral column, all of the ribs, all of the hindlimbs and part of the upper forelimbs; Sphodrosaurus was originally believed to have been a member of the Procolophonidae^[3] while more recently Sphodrosaurus was believed to be a basal member of the Diapsida by most authors starting with Sues et al. (1993),^[4] or a member of the Rhynchosauria (Baird, 1986^[5]). In 2022, Ezcurra & Sues redescribed the holotype in detail and placed it in a phylogenetic analysis with other Triassic diapsid reptiles, where it was found as the basalmost doswellid.^[6]

Sphodrosaurus Temporal range: Late Triassic, ~230–205.6 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Fossil
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Clade:	Archosauromorpha
Clade:	Archosauriformes
Genus:	†Sphodrosaurus Colbert, 1960
Species:	†S. pennsylvanicus
Binomial name
†Sphodrosaurus pennsylvanicus Colbert, 1960

References

1. "Sphodrosaurus Colbert, 1960". www.gbif.org. GBIF. Retrieved 2021-04-25.
2. "Fossilworks: Sphodrosaurus". fossilworks.org. Fossilworks. Retrieved 17 December 2021.
3. Colbert, E. H. (1960). A New Triassic Procolophonid from Pennsylvania. American Museum Novitates 2022:1-19
4. Sues, H-D., Baird, D., and Olsen, P.E. (1993). Redescription of Sphodrosaurus pennsylvanicus Colbert, 1960 (Reptilia) and a Reassessment of its Affinities. Annals of Carnegie Museum 62(3):245-253
5. Baird, D. (1986). Some Upper Triassic reptiles, footprints and an amphibian from New Jersey. The Mosasaur 3:125-153
6. Ezcurra, Martín D.; Sues, Hans-Dieter (2022-05-13). "A re-assessment of the osteology and phylogenetic relationships of the enigmatic, large-headed reptile Sphodrosaurus pennsylvanicus (Late Triassic, Pennsylvania, USA) indicates archosauriform affinities". Journal of Systematic Palaeontology. 19 (24): 1643–1677. doi:10.1080/14772019.2022.2057820. ISSN 1477-2019. S2CID 248785154.