Troodon Posted January 23, 2018 Share Posted January 23, 2018 Will try to take a better photo Croc. Link to comment Share on other sites More sharing options...
LordTrilobite Posted January 23, 2018 Author Share Posted January 23, 2018 On 1/23/2018 at 11:27 AM, Troodon said: At Tucson show Spinosaurid what position do you believe ? Caudal Rebbachisaurus? Looks like a reasonable match with paper. I definitely agree with the second and third vertebrae. Caudal Spinosaurid and dorsal Sauropod that matches Rebbachisaurus quite well. But that first one is really weird. I agree that it looks like Spinosaurid. The centrum is consistent with other Spinosaurid dorsal vertebrae with round flat back and slightly rounded front with a much thinner middle. But the dorsal spine is not consistent with any of the reconstructions of the sail of Spinosaurus. My thinking is that Sigilmassasaurus might not have had a sail as it seems to be more closely related to Baryonyx and Suchomimus than to Spinosaurus and the dorsal spines on it's cervical vertebrae aren't nearly as long as those on Spinosaurus that lead up to the sail. This vertebra, to me looks like the very end of a large sail. But it definitely looks like a dorsal vertebra. Most Spinosaurus reconstructions have the sail extending over the sacrum on to the base of the tail. Only the most recent reconstruction from Ibrahim has the sail ending earlier more towards the front. I think we're looking at a really interesting piece that might be evidence that the sail was even shorter than we wee on Ibrahim's reconstruction. It's worth noting that on this reconstruction the end of the sail area has the least bone information. All the blue bones here are only inferred and had no fossil evidence at the time. I think that this might be one of the last dorsal vertebrae, or possibly one of the first caudal vertebrae. Either way, I don't think this fits a probably sail-less Sigilmassasaurus, which makes it Spinosaurus, so the sail of Spinosaurus needs to be redrawn I think. Did you take any more pictures of that specimen? Suchomimus dorsal vertebrae do not seem to fit at all because the dorsal spines are much too straight. 1 Olof Moleman AKA Lord Trilobite Link to comment Share on other sites More sharing options...
Troodon Posted January 23, 2018 Share Posted January 23, 2018 I bought it so I will be able to take additional pictures when I bring it home. I'm in agreement with your thoughts on it and also think it's a dorsal. How about the front end instead of the back, the end of the spine is very round which seems to fit the reconstruction. Link to comment Share on other sites More sharing options...
LordTrilobite Posted January 23, 2018 Author Share Posted January 23, 2018 Great to hear such a beautiful vertebra is in your good hands! It can't be a dorsal vertebra from the front though. The convex end of the centrum is the front. So then the dorsal spine would curve the wrong way. No I think the sail of Spinosaurus might actually look more like that of the sail of Dimetrodon, where the dorsal spines rapidly curve backwards just before the sacrum. 4 Olof Moleman AKA Lord Trilobite Link to comment Share on other sites More sharing options...
Troodon Posted January 23, 2018 Share Posted January 23, 2018 Good point, the centrum is very large so it's from an adult. By the way the blue bones from the reconstruction were "inferred bones" so we really dont know what they looked like. Maybe more like your thought Dimetrodon like. Link to comment Share on other sites More sharing options...
LordTrilobite Posted January 25, 2018 Author Share Posted January 25, 2018 Here are a few more of my new vertebrae. I got a few nice vertebrae for Christmas that I think are cervical vertebrae of crocodiles. And I recently bought a Pterosaur cervical vertebra. Three cervical vertebrae. Pretty sure these are crocs. It's pretty interesting how the two smaller ones are fairly similar while the large one has quite a different shape. The foramina on the sides are also different. Different types of crocs maybe? Pterosaur cervical vertebra. And I'm fairly sure it's from an Azhdarchid too. None of the other Pterosaur families seem to have neck vertebrae that are this elongated. I still have to do some cleaning work though. Once I'm done I'll probably add it to the first post. And if anyone else still has some good examples of Kem Kem vertebrae, please share some photos so we can together get a better picture of the different types that are present in the Kem Kem beds. 1 Olof Moleman AKA Lord Trilobite Link to comment Share on other sites More sharing options...
Anomotodon Posted January 25, 2018 Share Posted January 25, 2018 What do you think about this vertebra? It is the specimen from this thread, I finally got it. Sorry for the quality, I am going to have better pics soon. Size 3.28" I am almost sure it is theropod cervical (#4-5-6?), it also looks a lot like Abelisaurid vert from the descriptions above. From what I understand, Allosaroid cervical vertebrae are more compressed and have a more convex proximal end (but I more of a tooth person rather than bone person, so not 100% sure). 1 The Tooth Fairy Link to comment Share on other sites More sharing options...
Troodon Posted January 26, 2018 Share Posted January 26, 2018 20 hours ago, LordTrilobite said: Here are a few more of my new vertebrae. I got a few nice vertebrae for Christmas that I think are cervical vertebrae of crocodiles. And I recently bought a Pterosaur cervical vertebra. Three cervical vertebrae. Pretty sure these are crocs. It's pretty interesting how the two smaller ones are fairly similar while the large one has quite a different shape. The foramina on the sides are also different. Different types of crocs maybe? Pterosaur cervical vertebra. And I'm fairly sure it's from an Azhdarchid too. None of the other Pterosaur families seem to have neck vertebrae that are this elongated. I still have to do some cleaning work though. Once I'm done I'll probably add it to the first post. And if anyone else still has some good examples of Kem Kem vertebrae, please share some photos so we can together get a better picture of the different types that are present in the Kem Kem beds. Agree Croc. Love that Pterosaur vert Link to comment Share on other sites More sharing options...
Troodon Posted January 26, 2018 Share Posted January 26, 2018 Better image of Croc vert Link to comment Share on other sites More sharing options...
LordTrilobite Posted January 26, 2018 Author Share Posted January 26, 2018 12 hours ago, Anomotodon said: What do you think about this vertebra? It is the specimen from this thread, I finally got it. Sorry for the quality, I am going to have better pics soon. Size 3.28" I am almost sure it is theropod cervical (#4-5-6?), it also looks a lot like Abelisaurid vert from the descriptions above. From what I understand, Allosaroid cervical vertebrae are more compressed and have a more convex proximal end (but I more of a tooth person rather than bone person, so not 100% sure). Oof that's a tough one. Actually I think this might be a caudal vertebra. I don't see an attachment for any ribs. And the square bottom seems like it could suggest the attachment of a chevron. Perhaps a photo of the underside might shed some light on this. Dunno what type of animal it is though. 22 minutes ago, Troodon said: Better image of Croc vert Nice, good nice complete example of a caudal croc vert way down the tail. Olof Moleman AKA Lord Trilobite Link to comment Share on other sites More sharing options...
Troodon Posted January 26, 2018 Share Posted January 26, 2018 2 minutes ago, LordTrilobite said: Oof that's a tough one. Actually I think this might be a caudal vertebra. I don't see an attachment for any ribs. And the square bottom seems like it could suggest the attachment of a chevron. Perhaps a photo of the underside might shed some light on this. Dunno what type of animal it is though. Nice, good nice complete example of a caudal croc vert way down the tail. Looks like a caudal for the reasons you stated. Not enough there to determine what critter. By the way I did take a hard look at that sauropod vert I posted a while back and in agreement it more of an Abelsaurids for the reasons you stated, thanks. Link to comment Share on other sites More sharing options...
LordTrilobite Posted January 26, 2018 Author Share Posted January 26, 2018 14 minutes ago, Troodon said: Looks like a caudal for the reasons you stated. Not enough there to determine what critter. By the way I did take a hard look at that sauropod vert I posted a while back and in agreement it more of an Abelsaurids for the reasons you stated, thanks. Would it be okay if I added the photos of that vert to the original post for better reference? It's a very nice vertebra and a good example. Olof Moleman AKA Lord Trilobite Link to comment Share on other sites More sharing options...
Troodon Posted January 26, 2018 Share Posted January 26, 2018 1 Link to comment Share on other sites More sharing options...
Anomotodon Posted January 26, 2018 Share Posted January 26, 2018 4 hours ago, LordTrilobite said: Oof that's a tough one. Actually I think this might be a caudal vertebra. I don't see an attachment for any ribs. And the square bottom seems like it could suggest the attachment of a chevron. Perhaps a photo of the underside might shed some light on this. Dunno what type of animal it is though. I did not expect it to be caudal... I thought that such parallelogram-like shape is typical for cervical vertebrae in the base of the neck (where it starts to curve in theropods, and in crocs vertebrae should different because their neck is more straight)? Both ends are complete, so the vertebra definitely had such shape in vivo. I can't find anything similar among dinosaur and crocodile caudal verts. The Tooth Fairy Link to comment Share on other sites More sharing options...
Anomotodon Posted January 26, 2018 Share Posted January 26, 2018 Also look at this Majungasaurus 5th cervical vert, in my opinion, it is very similar. Foramen is poorly preserved on my vert but can be seen on the last pic. 1 The Tooth Fairy Link to comment Share on other sites More sharing options...
LordTrilobite Posted January 26, 2018 Author Share Posted January 26, 2018 Yes, your vertebra has a parallelogram-like shape. But that could just be postmortem deformation. I honestly don't seen any other resemblance. I don't see a foramen, nor an attachment for the rib. the centrum on your vert is concave on both ends while on Majungasaurus it's convex on the front end. A boxy shape for a centrum is more typical of a caudal vertebra. And even though it's missing some pieces, there's still a whole lot present. So possibly with a good match it will still be placable to a certain type of animal. But at the moment I'm still gonna say caudal vert of an indeterminate reptile. Though it's giving me more a dinosaur vibe. Olof Moleman AKA Lord Trilobite Link to comment Share on other sites More sharing options...
Anomotodon Posted January 26, 2018 Share Posted January 26, 2018 28 minutes ago, LordTrilobite said: Yes, your vertebra has a parallelogram-like shape. But that could just be postmortem deformation. I honestly don't seen any other resemblance. I don't see a foramen, nor an attachment for the rib. the centrum on your vert is concave on both ends while on Majungasaurus it's convex on the front end. A boxy shape for a centrum is more typical of a caudal vertebra. And even though it's missing some pieces, there's still a whole lot present. So possibly with a good match it will still be placable to a certain type of animal. But at the moment I'm still gonna say caudal vert of an indeterminate reptile. Though it's giving me more a dinosaur vibe. I didn't pay attention to the shape of the ends, so now I see that you are right, thank you. It does not look compressed enough for abelisaurid and croc caudals, what do you think about Carcharodontosaurid caudal (maybe somewhere in the middle of the tail)? They are more box-shaped. 1 The Tooth Fairy Link to comment Share on other sites More sharing options...
LordTrilobite Posted January 26, 2018 Author Share Posted January 26, 2018 hm, still hard to tell. Olof Moleman AKA Lord Trilobite Link to comment Share on other sites More sharing options...
Troodon Posted January 28, 2018 Share Posted January 28, 2018 A Dealer described these three Verts as Carch...but are cervical Spinosaurids 1 Link to comment Share on other sites More sharing options...
LordTrilobite Posted January 29, 2018 Author Share Posted January 29, 2018 I'm quite sure all three are Spinosaurid mid cervical vertebrae. The misidentification is likely due to Sereno labeling a bunch of Sigilmassasaurus vertebrae as Carcharodontosaurus. This was before Evers et al. showed it was definitely a separate species as well as a Spinosaurid. Here is a cervicodorsal vertebra from Mapusaurus from South America. Looks nothing like those cervical vertebrae shown in your photos. And Evers labels this as an indeterminate Carcharodontosaur vertebra from Kem Kem. While when we look at Spinosaurids... Sigilmassasaurus mid cervical vertebra. And a cervical vertebra that Evers et al. labels as an indeterminate Spinosaur. Though in my opinion this is likely Spinosaurus aegyptiacus. While the dorsal spines are incomplete on all three vertebrae in your photos. They look a little tall to be Sigilmassasaurus. So I'm thinking all three are Spinosaurus mid cervical vertebrae. Sources: https://peerj.com/articles/1323/?utm_source=TrendMD&utm_campaign=PeerJ_TrendMD_1&utm_medium=TrendMD https://www.researchgate.net/publication/228655543_A_new_carcharodontosaurid_Dinosauria_Theropoda_from_the_Upper_Cretaceous_of_Argentina 5 Olof Moleman AKA Lord Trilobite Link to comment Share on other sites More sharing options...
Troodon Posted May 3, 2018 Share Posted May 3, 2018 Came across this 2016 paper which is paywalled but provided sufficient info in the abstract to add to this tread. May have a second Rebbachisaurid which would not be a surprise. The other element presented in the paper is a dorsal neural arch of titanosauriform which continues to support the theory of multiple sauropods in this fauna. https://www.sciencedirect.com/science/article/pii/S019566711300116X A caudal vertebra possessing several rebbachisaurid synapomorphies is excavated by a large and pervasive lateral pneumatic foramen, a feature undocumented in other rebbachisaurids. However, caudal vertebrae are currently unknown for the sympatric R. garasbae, so this element could be referable to that taxon or a second, previously unknown, rebbachisaurid species. 5 Link to comment Share on other sites More sharing options...
talon22 Posted May 8, 2018 Share Posted May 8, 2018 Mind if i add this to the thread......it is an impressive vertebra (currently for sale) at over 14 inches, and apparently from a Spinosaurid. Might try my luck at the bidding. Great thread btw, helping me a lot (since i know very little about Kem Kem vertebraes). 1 Link to comment Share on other sites More sharing options...
Troodon Posted May 8, 2018 Share Posted May 8, 2018 Very nice vertebra. Great photos.. One of diagnostic features present, possibly to determine the type of Spinosaurids, is found on the ventral surface. Could you take a photo of the base of your specimen. 1 Link to comment Share on other sites More sharing options...
LordTrilobite Posted May 8, 2018 Author Share Posted May 8, 2018 I was eyeing it up on the internet as well. It definitely looks like a nice vertebra. I agree that this does look like a Spinosaurid vertebra. It's a dorsal vertebra. And as Troodon says, the diagnostic features are on the ventral side. It looks like there is a ventral keel present, which make me think this might be Sigilmassasaurus, not Spinosaurus. But I don't think it's possible to get a conclusive ID without cleaning it because the most important feature on the posteroventral area of the centrum is covered in matrix. If it's Sigilmassasaurus brevicollis there should be a triangular rugose/rough area. If it's not present then it's more likely to be Spinosaurus aegyptiacus. Due to the likely presence of a ventral keel I would tentatively lean more towards Sigilmassasaurus. So right now, Spinosaurid dorsal vertebra of indeterminate species. With some proper cleaning it might be identifiable. And it also seems to have a repair that can be seen on the right in the last photo. 3 Olof Moleman AKA Lord Trilobite Link to comment Share on other sites More sharing options...
Tidgy's Dad Posted May 8, 2018 Share Posted May 8, 2018 Very nice piece. Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
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