Rhytidosteus

Rhytidosteus Temporal range: Early Triassic
Illustrations of the skull and a cross section of the tooth of Rhytidosteus capensis
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Tetrapoda
Order:	† Temnospondyli
Suborder:	† Stereospondyli
Superfamily:	† Rhytidosteoidea (?)
Family:	† Rhytidosteidae (?)
Genus:	† Rhytidosteus Owen, 1884
Type species
†Rhytidosteus capensis Owen, 1884

Life restoration

Rhytidosteus is an extinct genus of temnospondyl amphibian from the Early Triassic of South Africa. Initially described by Sir Richard Owen in 1884, the type species Rhytidosteus capensis was compared to the known labyrinthodont Mastodonsaurus and determined to be a unique species. ^[1]

Rhytidosteus uralensis originally published and described by Shishkin from the Orenberg region of Russia, has since been determined to be a junior synonym of R. capensis. ^[2]

Phylogeny

Rhytidosteus was made the type species for the family Rhytidosteidae by Friedrich von Huene, ^[3] however the placement of Rhytidosteus has become uncertain in recent studies. Dias-da-Silva and Marsicano recovered Rhytidosteus outside of Rhytidosteidae, ^[4] the authors attribute this result to the incompleteness of the fossil and indicate that further material would resolve the placement within the family. A 2014 study recovered a paraphyletic Rhytidosteidae, with Rhytidosteus only being recovered within Rhytidosteidae sensu stricto. ^[5]

References

1. Owen, R. (1884). "On a labyrinthodont amphibian (Rhytidosteus capensis) from the Trias of the Orange Free State, Cape of Good Hope". Quarterly Journal of the Geological Society. 40: 333–339. doi:10.1144/gsl.jgs.1884.40.01-04.30.
2. Shishkin, M. A. (1994). "A gondwanan rhytidosteid (Amphibia, Temnospondyli) from the Lower Triassic of Southern Cisuralia". Paleontological Journal. 28 (4): 127–143.
3. von Huene, Friedrich (1920). "GONIOGLYPTUS, EIN ALTTRIASSISCHER STEGOCEPHALE AUS INDIEN" (PDF). Acta Zoologica. 1 (3): 433–464.
4. Dias-da-Silva, S.; Marsicano, C. (2011). "Phylogenetic reappraisal of Rhytidosteidae (Stereospondyli: Trematosauria), temnospondyl amphibians from the Permian and Triassic". Journal of Systematic Palaeontology. 9 (2): 305–325. doi:10.1080/14772019.2010.492664.
5. Maganuco, S.; Pasini, G.; Auditore, M. (2014). "A revision of the short-faced stereospondyls Mahavisaurus dentatus and Lyrosaurus australis from the Lower Triassic of Madagascar: cranial anatomy, ontogenetic remarks, palaeoecology and rhytidosteid phylogeny". Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano. 39: 1–64.