gigantoraptor Posted May 31, 2020 Share Posted May 31, 2020 Hello all I have a question about these three big crocodylomorph teeth from the Kem Kem beds in Morocco. The Kem Kem beds are Cenomanian (early late Cretaceous) in age. These are my three teeth: The left one is an 8,5 cm long tooth crown (maybe partial rooted but not too much) which is very slender. It has carinae ( Correct term for Crocodilians?) running all the way along the crown. The middle one is a rooted, slender tooth of 9 cm with a missing tip. The first time I saw this tooth for a moment I thought it would be a Pliosaur tooth, until I saw the location. I am not sure if the missing tip is chewing damage or just because the fossil broke. The complete tooth would have been 9,3-9,5 cm I think. It does have carinae, but they don’t seem to run along the entire 4 cm long crown. The root itself is around 5 cm long and hollow. The last one is a very robust 6 cm long tooth crown with clear carinae running along the entire tooth. This tooth is way smaller than the first one, but a lot more robust. My problem with these teeth is ID’ing them. Crocodile teeth usually aren’t easy but I really wanted to try to get some ID on these. Some background info: So far seven Crocodylomorphs are described in the Kem Kem beds. 1: First of, Araripesuchus rattoides I couldn’t really find any good pictures of teeth from this species, but I found this picture of a jaw of Araripesuchus wegneri from Niger My teeth certainly do not belong to this genus because of size and shape. 2: Next, Laganosuchus maghrebensis, a species who’s teeth also don’t look similar to mine. 3: Hamadasuchus rebouli has pretty distinctive teeth. They are usually serrated and a lot smaller. 4: Next up, Aegisuchus witmeri, a croc with a holotype without any teeth. However, the size estimates given to this crocodile are too small to contain such big teeth, so I also rule this one out. 5: We also have Kemkemia auditorei, but this species is only known from caudal vertebra. According to Wikipedia (I know, great source), this would have been a crocodylomorph with a size of 4 to 5 meters. I can’t really comment on teeth of this species, but when I compared it with the largest tooth recorded (9cm) of the biggest crocodile today (Saltwater crocodile), this tooth was even larger than the biggest of the Saltwater crocodile, while that specific individual must have been 1 to 2 meters bigger than the 4 to 5 meter estimate on Kemkemia, so I think we can rule that species also out. 6: The last one I feel pretty confident in ruling out is Lavocatchampsa sigogneaurusselae. Beside being way to small, it’s teeth looks nothing like mine. 7: Now onto the most famous Kem Kem crocodile: Elosuchus cherifiensis. The original description of the genus Elosuchus included these teeth. According to the description and this picture, I am pretty sure the tooth on the right does belong to this species. The other two teeth do not fit this description however. For the tooth on the left one I can believe it’s a different position in the jaw, but I am far from sure. The middle tooth is something else I think. It could of course be a case of heterodonty, but it differs quite a lot from the two others. So what do you guys think? Is this a case of heterodonty, or is there some huge, undescribed crocodylomorph present in the Kem Kem beds? Really looking forward to what you think. Pictures from: Larsson, H. C. E., en C. A. Sidor. “Unusual Crocodyliform Teeth from the Late Cretaceous (Cenomanian) of Southeastern Morocco”. Journal of Vertebrate Paleontology 19, nr. 2 (1999): 398–401. Martin, Jeremy E., en France De Lapparent De Broin. “A Miniature Notosuchian with Multicuspid Teeth from the Cretaceous of Morocco”. Journal of Vertebrate Paleontology 36, nr. 6 (november 2016). Sereno, Paul, en Hans Larsson. “Cretaceous Crocodyliforms from the Sahara”. ZooKeys 28 (19 november 2009): 1–143. Lapparent de Broin, France de. “Elosuchus, a New Genus of Crocodile from the Cretaceous of the North of Africa”. Comptes Rendus Palevol 1, nr. 5 (1 december 2002): 275. 8 Link to comment Share on other sites More sharing options...
Troodon Posted May 31, 2020 Share Posted May 31, 2020 Ibrahim et al. most recent paper on the fauna of the KK identifies all those you cite plus one indet. and less Kemkemia which is regarded as nomen dubium. See faunal list from paper Your two outer teeth may just be positional or the right one a replacement tooth. Are you sure the middle one is croc and from the KK group? Here are the teeth of Hamadasuchus and it has pretty big incisors Araripesuchus rattoides Geology and paleontology of the Upper Cretaceous Kem Kem Group of eastern Morocco, 2020 Nizar Ibrahim, Paul C. Sereno, David J. Varricchio, David M. Martill, Didier B. Dutheil, David M. Unwin, Lahssen Baidder, Hans C.E. Larsson, Samir Zouhri, Abdelhadi Kaoukaya 8 Link to comment Share on other sites More sharing options...
gigantoraptor Posted June 1, 2020 Author Share Posted June 1, 2020 15 hours ago, Troodon said: Your two outer teeth may just be positional or the right one a replacement tooth. Are you sure the middle one is croc and from the KK group? Hello Troodon and thanks for your answer. Yes, from the two outer ones I suspected it might be positional, but I was not sure. These at least look a bit like each other. The sediment that's left on the tooth points to Kem Kem, and the seller sold some other fossils from the same location, so I am pretty certain this is indeed a Kem Kem tooth. Am I sure it's crocodile? No, but I don't see what else it could be. It's not dinosaurian, doesn't look like a fish tooth either. So that left crocs. As said before, at first glance I thought this was a Pliosaur tooth, but I kinda ruled that one out since Plesiosaurs are extremely rare and Pliosaurs unheard of in the Kem Kem beds. 15 hours ago, Troodon said: Here are the teeth of Hamadasuchus and it has pretty big incisors I don't think it's a Hamadasuchus incisor, since those seem to be faceted and my tooth is not. Picture from: Larsson HCE, Sues H-D (2007) Cranial osteology and phylogenetic relationships of Hamadasuchus rebouli (Crocodyliformes: Mesoeucrocodylia) from the Cretaceous of Morocco. Zoological Journal of the Linnean Society 149: 533–567. Link to comment Share on other sites More sharing options...
Troodon Posted June 1, 2020 Share Posted June 1, 2020 Your outer teeth look like Elosuchus but the other one is a mystery. Kind of looks like a whale incisor Link to comment Share on other sites More sharing options...
gigantoraptor Posted June 1, 2020 Author Share Posted June 1, 2020 12 minutes ago, Troodon said: Your outer teeth look like Elosuchus but the other one is a mystery. Kind of looks like a whale incisor I have no experience with whale teeth, but from pictures online I feel like those have a smooth tooth surface, while this one has kind of very tiny vertical ridges. Link to comment Share on other sites More sharing options...
Anomotodon Posted June 2, 2020 Share Posted June 2, 2020 The middle one is very interesting, do you have any more pictures? Are those fine striations on the surface? Theoretically there could be pliosaurs in Ifezouane, they certainly are known from other Kem Kem assemblages (like Akrabou), but I haven't seen any 1 The Tooth Fairy Link to comment Share on other sites More sharing options...
gigantoraptor Posted June 2, 2020 Author Share Posted June 2, 2020 5 hours ago, Anomotodon said: The middle one is very interesting, do you have any more pictures? Are those fine striations on the surface? Theoretically there could be pliosaurs in Ifezouane, they certainly are known from other Kem Kem assemblages (like Akrabou), but I haven't seen any Thanks for your answer. Do any of these pictures help? It looks like very faint striations. Link to comment Share on other sites More sharing options...
Troodon Posted June 2, 2020 Share Posted June 2, 2020 Send a photos and detail info to Christophe Hendrickx. I'm sure he can resolve this. Link to comment Share on other sites More sharing options...
gigantoraptor Posted June 2, 2020 Author Share Posted June 2, 2020 52 minutes ago, Troodon said: Send a photos and detail info to Christophe Hendrickx. I'm sure he can resolve this. I did, but he does not want to identify fossils bought on the market. Link to comment Share on other sites More sharing options...
Troodon Posted June 2, 2020 Share Posted June 2, 2020 Thats unfortunate since lots specimens published in papers are commercially obtained from KK deposits. Very odd since his paper on Spinosaurid quadrates clearly states that some of the specimens used were commercially obtained. He's also addressed other member teeth from the KK that were commercially obtained. Possibly he does not know and uses that as an out. Does not add up. Link to comment Share on other sites More sharing options...
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