Trachelosaurus

Trachelosaurus Temporal range: Early Triassic, 247–242  Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Holotype specimen
Reconstructed skeleton of the holotype
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Clade:	Archosauromorpha
Family:	† Trachelosauridae
Genus:	† Trachelosaurus Broili & Fischer, 1917
Species:	†T. fischeri
Binomial name
†Trachelosaurus fischeri Broili & Fischer, 1917

Trachelosaurus is an extinct genus of lizard-like early archosauromorph reptiles in the family Trachelosauridae. ^[1] It was originally described as a dinosaur ^[2] until it was redescribed as a "protorosaur" reptile by Robert L. Carroll in 1988. ^[3] The type species, T. fischeri, was described by F. Broili & E. Fischer in 1917 ^[2] based on remains found in the Solling Formation (Buntsandstein), Bernburg, Germany. ^[4] A 2024 redescription identified Trachelosaurus as a long-necked and presumably aquatic reptile closely related to Dinocephalosaurus from the Guanling Formation of China. ^[5]

Size compared to a human

Classification

In their 2024 redescription of Trachelosaurus, Spiekman and colleagues recovered it in a clade with the Chinese Dinocephalosaurus in a clade previously named Dinocephalosauridae in 2021. However, the principle of priority instructs that the name Trachelosauridae, which was first erected as a monotypic clade for Trachelosaurus, should be used instead. The results of their phylogenetic analyses are shown in the cladogram below: ^[5]

Tanysauria	Jesairosaurus Trachelosauridae Austronaga Pectodens Fuyuansaurus Trachelosaurus Gracilicollum Dinocephalosaurus Tanystropheidae Augustaburiania Luxisaurus Macrocnemus bassanii Macrocnemus fuyuanensis Macrocnemus obristi UFRGS-PV-492-T Amotosaurus Langobardisaurus Raibliania Tanystropheus spp. Sclerostropheus Ozimek Tanytrachelos

References

1. O. Kuhn. (1971). Reptiles of the German Triassic . 1-105
2. F. Broili and E. Fischer. (1917). Trachelosaurus fischeri nov. gen. nov. sp. A new dinosaur from the Buntsandstein of Bernburg. Jahrbuch der Königlich Preussischen geologischen Landesanstalt zu Berlin 37(1):359-414
3. R. L. Carroll. (1988). Vertebrate Paleontology and Evolution 1-698
4. H. H. Ecke. (1986). Palynologie des Zechsteins und Unteren Buntsandsteins im Germanischen Becken. Dissertation Georg-August-Universität Göttingen 1-117
5. Spiekman, Stephan N. F.; Ezcurra, Martín D.; Rytel, Adam; Wang, Wei; Mujal, Eudald; Buchwitz, Michael; Schoch, Rainer R. (2024-03-15). "A redescription of Trachelosaurus fischeri from the Buntsandstein (Middle Triassic) of Bernburg, Germany: the first European Dinocephalosaurus-like marine reptile and its systematic implications for long-necked early archosauromorphs". Swiss Journal of Palaeontology . 143 (1): 10. doi: 10.1186/s13358-024-00309-6 . ISSN   1664-2384.