Rhadinosaurus

Rhadinosaurus Temporal range: Late Cretaceous, 84.9–70.6 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Dinosauria
Clade:	†Ornithischia
Clade:	†Thyreophora
Clade:	†Ankylosauria
Clade:	†Euankylosauria
Family:	†Nodosauridae
Genus:	†Rhadinosaurus Seeley, 1881
Species:	†R. alcimus
Binomial name
†Rhadinosaurus alcimus Seeley, 1881

Rhadinosaurus (meaning "slender lizard") is a genus of nodosaurid ankylosaur first described in 1881 by Harry Govier Seeley, based on remains uncovered in Austria sometime between 1859 and 1870 by Edward Suess and Pawlowitsch.^[1] It was a herbivore that lived around 84.9 to 70.6 million years ago (during the Late Cretaceous period).^[2] The type species is R. alcimus.

Fossils

The Rhadinosaurus hypodigm (holotype) consists of one tibia fragment, one limb fragment, two fibulae, and two dorsal vertebrae. The fibulae (PIUW 2349/34), which are clearly ankylosaurian, were originally identified as femora in the original description, but were eventually re-identified in a 2001 review of ankylosaur specimens from the Grünbach Formation.^[3] Sachs and Hornung (2006) re-identified one of the putative humeral bones (PIUW 2348/35) as a tibial fragment of an rhabdodontid ornithopod dinosaur, referring it to Zalmoxes sp.^[4]

Taxonomy

Rhadinosaurus was initially classified as a dinosaur of uncertain position, and later considered an ornithosuchid as well as possible synonym of Doratodon, until Franz Nopcsa introduced the now popular theory that classifies it as a probable synonym of Struthiosaurus.^{[3][5][6][7][8]}

References

1. H.G. Seeley, (1881), "The reptile fauna of the Gosau Formation preserved in the Geological Museum of the University of Vienna", Quarterly Journal of the Geological Society of London 37(148): 620–707
2. "Fossilworks: Rhadinosaurus alcimus". fossilworks.org. Retrieved 17 December 2021.
3. X. Pereda Suberbiola and P. M. Galton. 2001. Reappraisal of the nodosaurid ankylosaur Struthiosaurus austriacus Bunzel from the Upper Cretaceous Gosau Beds of Austria. In K. Carpenter (ed.), The Armored Dinosaurs. Indiana University Press, Bloomington 173–210
4. Sachs, S; Hornung, J (2006). Juvenile ornithopod (Dinosauria: Rhabdodontidae) remains from the Upper Cretaceous (Lower Campanian, Gosau Group) of Muthmannsdorf (Lower Austria). Geobios. 39 (3): 415–425. doi:10.1016/j.geobios.2005.01.003.
5. B. F. Nopcsa. 1915. Die dinosaurier der Siebenbürgischen landesteile Ungarns [Dinosaurs of the Transylvanian regions of Hungary]. Mitteilungen aus dem Jahrbuche der Kgl. Ungarischen Geologischen Reichsanstalt 23:1-24.
6. F. Nopcsa. 1923. On the geological importance of the primitive reptilian fauna in the uppermost Cretaceous of Hungary; with a description of a new tortoise (Kallokibotion). Quarterly Journal of the Geological Society 74:100-116.
7. A. S. Romer. 1956. Osteology of the Reptiles, University of Chicago Press 1-772.
8. Steel, R. (1973). Handbuch der Paleoherpetologie. Vol. 16: Crocodilia. Fischer-Verlag, Portland, Oregon. 116pp.