Joseph Fossil Posted January 8, 2023 Share Posted January 8, 2023 A while back, I was researching the number of likely Tyrannosauroidea dinosaurs that inhabited the Southern Hemisphere (I know this is a very controversial subject) in the Early Cretaceous for an extra credit research paper I was doing for my freshmen year college geology class. As I was looking for data for the paper, I found an unusual data entry on the paleontological database website fossilworks.org - It lists Tyrannosauridae remains from Jurassic Madagascar. http://www.fossilworks.org/cgi-bin/bridge.pl?a=collectionSearch&collection_no=55391 The specimen MSNM V5819 (consisting of a partial tooth) was apparently found in Mahajanga, Madagascar at the Bathonian aged Isalo Illb Formation (dating 167.7-164.7 million years ago) in 2003. S. Maganuco, A. Cau, and G. Pasini (2005) First description of theropod remains from the Middle Jurassic (Bathonian) of Madagascar. Atti della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano, 146(2):165-202 https://www.researchgate.net/publication/257651210_First_description_of_theropod_remains_from_the_Middle_Jurassic_Bathonian_of_Madagascar (You can read the actual paper with this above link). Here is also two photographs from the paper of the specimen MSNM V5819 The authors of the paper (which I must say did a really good job with the research and paper itself) state that a healthy degree of caution must be given in assigning MSNM V5819 to Tyrannosauroidea. Still, if this is indeed correct, It would be one of the earliest members of Tyrannosauroidea, with the only currently known older Tyrannosauroidea taxon being Proceratosaurus of England. The Specimen MSNM V5819 is maybe even older than Kileskus of Russia, Guanlong of China, and Aviatyrannus of Portugal. Still, the only currently known specimen is a single tooth, MSNM V5819, and I'm not 100% certain this represents a member of Tyrannosauroidea? What do you guys think? 1 Link to comment Share on other sites More sharing options...
Troodon Posted January 9, 2023 Share Posted January 9, 2023 A new specimen MSNM V6234 was examined in the attached paper and found to be similar to MSNM V5819 both described as morph 8 "Some resemblance with tyrannosauroid teeth can still be noticed, but the similarities with derived members of the group appear weaker, advanced tyrannosauroids having both crowns and denticles more expanded labiolingually (pers. obs., 2004) than MSNM V6234." "basis of the present evidence, the teeth referred to morphotype 8 may belong to a basal tetanuran theropod, but their affinities cannot be ascertained, pending associated skeletal material. Therefore we regard the specimen MSNM V6234 as Theropoda incertae sedis." https://www.researchgate.net/publication/257651213_Evidence_of_large_theropods_from_the_Middle_Jurassic_of_the_Mahajanga_Basin_NW_Madagascar_with_implications_for_ceratosaurian_pedal_ungual_evolution 1 Link to comment Share on other sites More sharing options...
Joseph Fossil Posted January 9, 2023 Author Share Posted January 9, 2023 35 minutes ago, Troodon said: A new specimen MSNM V6234 was examined in the attached paper and found to be similar to MSNM V5819 both described as morph 8 "Some resemblance with tyrannosauroid teeth can still be noticed, but the similarities with derived members of the group appear weaker, advanced tyrannosauroids having both crowns and denticles more expanded labiolingually (pers. obs., 2004) than MSNM V6234." "basis of the present evidence, the teeth referred to morphotype 8 may belong to a basal tetanuran theropod, but their affinities cannot be ascertained, pending associated skeletal material. Therefore we regard the specimen MSNM V6234 as Theropoda incertae sedis." https://www.researchgate.net/publication/257651213_Evidence_of_large_theropods_from_the_Middle_Jurassic_of_the_Mahajanga_Basin_NW_Madagascar_with_implications_for_ceratosaurian_pedal_ungual_evolution @Troodon Thanks for letting me know, Can't believe I missed that. How possible do you think it is that Specimens MSNM V6234 and MSNM V5819 are from Tyrannosauroidea or do you think they belong to another theropod group? Link to comment Share on other sites More sharing options...
Troodon Posted January 9, 2023 Share Posted January 9, 2023 I believe what the paper said "Theropoda incertae sedis". Need more discoveries and its way you early to make any claims especially since this paper does not support that assignment 1 Link to comment Share on other sites More sharing options...
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