Alston Gee Posted December 24, 2020 Share Posted December 24, 2020 I propose to buy this specimen if it is real. The seller told me that this specimen should belong to the pliosaur based on his experience, but I had a hard time to identify whether it is an ichthyosaur tooth or a pliosaur tooth. Is it an ichthyosaur tooth or a pliosaur tooth? Link to comment Share on other sites More sharing options...
Alston Gee Posted December 24, 2020 Author Share Posted December 24, 2020 Link to comment Share on other sites More sharing options...
PaleoNoel Posted December 24, 2020 Share Posted December 24, 2020 I think it may be ichthyosaur. I believe one of the last ichthyosaurs, platypterygius is known from this formation in Russia. However, marine reptiles are not my forte. @pachy-pleuro-whatnot-odon Link to comment Share on other sites More sharing options...
-Andy- Posted December 24, 2020 Share Posted December 24, 2020 The size and morphology reminds me of my ichthyosaur Platypterygius sp. as if it had its root broken off. I say it's the same species 1 Looking forward to meeting my fellow Singaporean collectors! Do PM me if you are a Singaporean, or an overseas fossil-collector coming here for a holiday! Link to comment Share on other sites More sharing options...
RuMert Posted December 24, 2020 Share Posted December 24, 2020 Certainly looks more like ichthyosaur. The formation here is most likely Cenomanian or Albian-Cenomanian (Belgorod Oblast, Stary Oskol, OJSC Stoilensky GOK) and possible pliosaur genera are Leptocleidus or Polyptychodon. Ichthyosaur teeth are also numerous there. In other regions (Ryazan Oblast, for example), 90% of such Cretaceous teeth will belong to pliosaurs 4 My sites & reports Link to comment Share on other sites More sharing options...
pachy-pleuro-whatnot-odon Posted December 24, 2020 Share Posted December 24, 2020 Yeah, I'd also say this is ichthyosaur, Platypterygius sp.. In absence of the root, you can tell by the rounded folds (known as plicidentine) on the tooth crown - and often on the root too, but less often so in derived species such as Platypterygius - versus the much sharper, and rather square looking striations on pliosaur teeth. Another trade of derived ophthalmosaurid ichthyosaurs, such as Platypterygius is that the striations terminate before reaching the tooth apex, as is the case here. A further differentiating trait is that in most pliosaur species, the striations are not as equally distributed, nor do they all stop at the same height, as in this specimen... 4 'There's nothing like millions of years of really frustrating trial and error to give a species moral fibre and, in some cases, backbone' -- Terry Pratchett Link to comment Share on other sites More sharing options...
pachy-pleuro-whatnot-odon Posted December 24, 2020 Share Posted December 24, 2020 3 hours ago, RuMert said: Certainly looks more like ichthyosaur. The formation here is most likely Cenomanian or Albian-Cenomanian (Belgorod Oblast, Stary Oskol, OJSC Stoilensky GOK) and possible pliosaur genera are Leptocleidus or Polyptychodon. Ichthyosaur teeth are also numerous there. In other regions (Ryazan Oblast, for example), 90% of such Cretaceous teeth will belong to pliosaurs It should be noted that validity of Polyptychodon as a genus is disputed, whereas Leptocleidus is a Jurassic genus - thus the tooth found in Belgorod Oblast would better be called Leptocleididae - with closer alterations to plesiosauria than to pliosauria, according to recent cladistic analysis: 4 'There's nothing like millions of years of really frustrating trial and error to give a species moral fibre and, in some cases, backbone' -- Terry Pratchett Link to comment Share on other sites More sharing options...
RuMert Posted December 24, 2020 Share Posted December 24, 2020 Yep, Leptocleididae is better. They are still popularly regarded as pliosaurs here, though they are known not to be true ones. A seller would call it so, 100% sure My sites & reports Link to comment Share on other sites More sharing options...
pachy-pleuro-whatnot-odon Posted December 24, 2020 Share Posted December 24, 2020 3 hours ago, RuMert said: Yep, Leptocleididae is better. They are still popularly regarded as pliosaurs here, though they are known not to be true ones. A seller would call it so, 100% sure It's no different with the Moroccan material from Goulmima (though in particular with respect to bone material rather than teeth), much of which is actually polycotylid in nature, to judge by the teeth and cranial elements being found there. I guess pliosaurs are simply cooler than any other type of plesiosaur, making sellers want to hitch a ride on their popularity... 'There's nothing like millions of years of really frustrating trial and error to give a species moral fibre and, in some cases, backbone' -- Terry Pratchett Link to comment Share on other sites More sharing options...
RuMert Posted December 25, 2020 Share Posted December 25, 2020 Yes, apex predators, banana-sized teeth and so on - that's what many people imagine My sites & reports Link to comment Share on other sites More sharing options...
siteseer Posted December 25, 2020 Share Posted December 25, 2020 A few large pliosaur teeth from Stary Oskol appeared on the market in the late 90's. I saw one that had a crown maybe 3-4 inches long with some root. Some ichthyosaur and shark teeth were available. I saw maybe a couple of bones. Link to comment Share on other sites More sharing options...
pachy-pleuro-whatnot-odon Posted December 25, 2020 Share Posted December 25, 2020 Could've been a single specimen discovered then, with such huge teeth? Because I don't think any of those size have been around either before or after... 'There's nothing like millions of years of really frustrating trial and error to give a species moral fibre and, in some cases, backbone' -- Terry Pratchett Link to comment Share on other sites More sharing options...
Jaimin013 Posted April 1, 2021 Share Posted April 1, 2021 (edited) @RuMert @pachy-pleuro-whatnot-odon I've just seen this post and thought that I'd post pics of my Pliosaur tooth from Russia for comparison against the tooth in OPs post. The tooth is about 10cm in length so just under 4 inches. Any idea of the species? Probably not able to say for sure but I've been reading a bit and haven't found alot of material. Edited April 1, 2021 by Jaimin013 1 2 Link to comment Share on other sites More sharing options...
Svetlana Posted April 2, 2021 Share Posted April 2, 2021 (edited) 21 hours ago, Jaimin013 said: @RuMert @pachy-pleuro-whatnot-odon I've just seen this post and thought that I'd post pics of my Pliosaur tooth from Russia for comparison against the tooth in OPs post. The tooth is about 10cm in length so just under 4 inches. Any idea of the species? Probably not able to say for sure but I've been reading a bit and haven't found alot of material. I apologize for getting into someone else's topic, but I cannot remain silent: this tooth is something! Do you have more material on marine reptiles that you can show? Edited April 2, 2021 by Svetlana 1 Link to comment Share on other sites More sharing options...
Jaimin013 Posted April 2, 2021 Share Posted April 2, 2021 3 hours ago, Svetlana said: I apologize for getting into someone else's topic, but I cannot remain silent: this tooth is something! Do you have more material on marine reptiles that you can show? No problem unfortunately I don't have any other marine reptile fossils from Russia but have a 2 Ichthyosaurus teeth from the UK. I'm certainly however looking to expand my collection in the future. I love marine reptiles! Link to comment Share on other sites More sharing options...
pachy-pleuro-whatnot-odon Posted April 3, 2021 Share Posted April 3, 2021 On 4/1/2021 at 9:28 PM, Jaimin013 said: @RuMert @pachy-pleuro-whatnot-odon I've just seen this post and thought that I'd post pics of my Pliosaur tooth from Russia for comparison against the tooth in OPs post. The tooth is about 10cm in length so just under 4 inches. Any idea of the species? Probably not able to say for sure but I've been reading a bit and haven't found alot of material. Oh, wow! This one ended up with you? When it comes to determining what genus or species a pliosaur tooth belongs to, dating is about as important as morphology. As I know this tooth is said to have come from the "Volga Beds" (@RuMert's home turf), it could basically date to any point in time ranging from the Upper Jurassic - Kimmeridgian and Tithonian - through the Early Cretaceous, especially since it can be difficult to separate these stages in the field. Seeing as the pristine condition this tooth, however, it can't have been exposed for long before collection, meaning it was likely collected from matrix/the cliffs, rather than from the foreshore - and may even have come from the shale mines, as my guess is it would've been found somewhere in the late 1990's, early 2000's (I saw the tooth advertised in 2018, when it was stated it had been in the seller's collection for a decade after having been originally acquired from a U.S. collector). This lends greater credibility to the Early Tithonian date attributed by the seller I saw this tooth with (image below). The tooth being Late Jurassic is somewhat problematic, however, as Upper Jurassic pliosaur teeth are traditionally considered to be (sub)trihedral, even though evidence is accumulating as to this not being the only morphotype around during that interval (see here for a discussion). All the same, in absence of descriptions of species with conical teeth restricted to the Late Jurassic, we need to fall back to those genera and species described for the earlier stages of the Jurassic, most notably Oxfordian and Callovian. We only need to consider the more derived thalassophonea like Liopleurodon and Simolestes, however, as the teeth of species like Peloneustes philarchus and "Pliosaurus" andrewsi are much more gracile and more plesiosaurian in nature. Looking at the area of enamel without striae, one of the first things to notice is that the enamel is vermiculated, which is a feature characteristic of Liopleurodon. I also think I'm seeing a couple of reticulating striations near the base of the tooth, which would further argue in favour of Liopleurodon. Moreover, I think the size of this tooth might be pushing past the limits of Simolestes. The striations on this tooth are quite densely packed, however, which is untypical for any of the known species of Liopleurodon. If this were a Cretaceous tooth, I'd be more than happy to attribute it to a brachauchenine pliosaur, for example. Compare with the below images: Owen's Polypthychodon continuus, now a nomen dubium genus. Figure 2 from Madzia (2016). Especially specimens B and C. Figure 4 from Madzia (2016). Liopleurodon ferox specimens: as illustrated by Sven Saches; Natural History Museum, accession number PV R 2449; and at Wollaton Hall, by Sven Sachs. However, when it comes down to it, I think your tooth, in the end, is what the label says it is: Liopleurodon sp.. May be not L. ferox, and certainly not L. pachydeirus (image below). But to the best of my understanding I would still class it in the genus. Teeth of Liopleurodon pachydeirus at the Natural History Museum, accession number PV R 2450. Identified by Leslie Noè. 1 'There's nothing like millions of years of really frustrating trial and error to give a species moral fibre and, in some cases, backbone' -- Terry Pratchett Link to comment Share on other sites More sharing options...
Jaimin013 Posted April 5, 2021 Share Posted April 5, 2021 (edited) On 4/3/2021 at 1:11 AM, pachy-pleuro-whatnot-odon said: Oh, wow! This one ended up with you? When it comes to determining what genus or species a pliosaur tooth belongs to, dating is about as important as morphology. As I know this tooth is said to have come from the "Volga Beds" (@RuMert's home turf), it could basically date to any point in time ranging from the Upper Jurassic - Kimmeridgian and Tithonian - through the Early Cretaceous, especially since it can be difficult to separate these stages in the field. Seeing as the pristine condition this tooth, however, it can't have been exposed for long before collection, meaning it was likely collected from matrix/the cliffs, rather than from the foreshore - and may even have come from the shale mines, as my guess is it would've been found somewhere in the late 1990's, early 2000's (I saw the tooth advertised in 2018, when it was stated it had been in the seller's collection for a decade after having been originally acquired from a U.S. collector). This lends greater credibility to the Early Tithonian date attributed by the seller I saw this tooth with (image below). The tooth being Late Jurassic is somewhat problematic, however, as Upper Jurassic pliosaur teeth are traditionally considered to be (sub)trihedral, even though evidence is accumulating as to this not being the only morphotype around during that interval (see here for a discussion). All the same, in absence of descriptions of species with conical teeth restricted to the Late Jurassic, we need to fall back to those genera and species described for the earlier stages of the Jurassic, most notably Oxfordian and Callovian. We only need to consider the more derived thalassophonea like Liopleurodon and Simolestes, however, as the teeth of species like Peloneustes philarchus and "Pliosaurus" andrewsi are much more gracile and more plesiosaurian in nature. Looking at the area of enamel without striae, one of the first things to notice is that the enamel is vermiculated, which is a feature characteristic of Liopleurodon. I also think I'm seeing a couple of reticulating striations near the base of the tooth, which would further argue in favour of Liopleurodon. Moreover, I think the size of this tooth might be pushing past the limits of Simolestes. The striations on this tooth are quite densely packed, however, which is untypical for any of the known species of Liopleurodon. If this were a Cretaceous tooth, I'd be more than happy to attribute it to a brachauchenine pliosaur, for example. Compare with the below images: Owen's Polypthychodon continuus, now a nomen dubium genus. Figure 2 from Madzia (2016). Especially specimens B and C. Figure 4 from Madzia (2016). Liopleurodon ferox specimens: as illustrated by Sven Saches; Natural History Museum, accession number PV R 2449; and at Wollaton Hall, by Sven Sachs. However, when it comes down to it, I think your tooth, in the end, is what the label says it is: Liopleurodon sp.. May be not L. ferox, and certainly not L. pachydeirus (image below). But to the best of my understanding I would still class it in the genus. Teeth of Liopleurodon pachydeirus at the Natural History Museum, accession number PV R 2450. Identified by Leslie Noè. Hi there! It sure did! Thanks very much this is super helpful! Glad to know that I can label it as a Liopluerodon, I did think it was too large for Simolestus ! Edited April 5, 2021 by Jaimin013 Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now