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ziggycardon posted a topic in Fossil IDHi! I recently aqcuired quite a lot of "microfossils" to kick off my Triassic collection, as I personally find it one of the most interesting time periods and while I am aware possibly not all of them are ID'd correctly I just wanted to get some nice fossils from this time period regardless of their ID's. All the fossils I acquired are from the Bull Canyon Formation, Dockum Group, San Miguel County, New Mexico, USA (Norian age) But I myself am not very knowledgeable yet in this material as I just started my collection but I am aware that some if not most of the ID's on these fossils given by the seller might be wrong as everything I read about the Bull Canyon formation says that the formation isn't that well discribed yet. I tried to make the photo's as good as I could, but it wasn't always easy given their extremely small size, so I hope the quality is good enough to work with. So I am kinda hoping is someone here on the forum would like to give it a try to see if he/she could confirm or disprove given ID's. Thank you in advance! The first set of 2 teeth were listed as the Phytosaur "Pseudopalatus" teeth which after doing a bit of research is considered a junior synonym for "Machaeroprosopus" The next collection of 3 teeth were listed as the Pseudosuchian "Revueltosaurus" The next tooth was listed as a "Theropod indet" tooth, and I know there are at least 2 species of theropod present at Bull Canyon, a Coelophysid called Gojirasaurus and a herrerasaurid called Chindesaurus. But I am not even sure whether this tooth is dinosaurian or not. The next set of teeth were listed as "Arganodus" lungfish teeth And the final tooth was listed as a "Sphenodont" (Rhynchocephalia indet.) tooth with affinities to Clevosaurus (which is found in Nova Scotia, Great Britain and China)
Hey everyone I recently found this paper on ResearchGate.. thought some people might want to see it. The paper basically describes the skeletal remains of various archosauriform taxa from a new Triassic bone assemblage from the Post Quarry (Dockum Group; Texas). The taxa described include Vancleavea campi and a new silesaurid (Soumyasaurus aenigmaticus - see below). Here's the RG link: https://www.researchgate.net/publication/327020021_Description_of_a_multitaxic_bone_assemblage_from_the_Upper_Triassic_Post_Quarry_of_Texas_Dockum_Group_including_a_new_small_basal_dinosauriform_taxon Sarigül, Agnolín and Chatterjee (2018) - Description of a multitaxic bone assemblage from the Upper Triassic Post Quarry of Texas (Dockum Group), including a new small basal dinosauriform taxon Abstract: A bone assemblage composed of intermixed small cranial and postcranial fragments from the Post Quarry of Texas, USA, is described. The skeletal elements represent multiple individuals of different taxa, including a partial dorsal column assigned to Vancleavea campi and an incomplete dentary referred to a new genus and species of a small-sized basal dinosauriform. Ankylothecodont dental implantation of the dinosauriform dentary bears strong resemblance to silesaurids. A fragmentary archosauromorph braincase is another intriguing element of the assemblage; it displays a striking contrast of a derived otoccipital on a plesiomorphic basioccipital. Poor preservation prevents more conclusive taxonomic assignments for the rest of the skeletal elements. The observed attrition and entangling in this bone assemblage reflect the complexities of the Dockum land tetrapod taphonomy. Partial dentary of S. aenigmaticus
A new article is now available online: Michelle R. Stocker; Sterling J. Nesbitt; Katharine E. Criswell; William G. Parker; Lawrence M. Witmer; Timothy B. Rowe; Ryan Ridgely; Matthew A. Brown (2016). "A Dome-Headed Stem Archosaur Exemplifies Convergence among Dinosaurs and Their Distant Relatives". Current Biology. in press. doi:10.1016/j.cub.2016.07.066. Triopticus is just another one of the many additions of the list of Triassic reptiles that are superficially similar to dinosaurs but fall outside Dinosauromorpha. This discovery brings to mind the putative Triassic pachycephalosaur from India (mentioned in Naish and Martill 2001 and Butler and Sullivan 2009), and it's almost certain that the "Triassic pachycephalosaur" could be a relative of Triopticus, since the putative pachycephalosaur classification of the Indian form, like the ornithomimosaur classification of Shuvosaurus and avialan classification of Protoavis, was greeted with skepticism by Chatterjee's critics. R. J. Butler and R. M. Sullivan, 2009. The phylogenetic position of Stenopelix valdensis from the Lower Cretaceous of Germany and the early fossil record of Pachycephalosauria. Acta Palaeontologica Polonica 54(1): 21-34 Naish, D. and Martill, D.M. 2001. Boneheads and horned dinosaurs. In: D.M. Martill and D. Naish (eds.), Dinosaurs of the Isle of Wight, 133–146. The Palaeontological Association, London.