Liopleurodon/pliosaur Tooth?

[Pliosaur]

Wonder if this tooth comes from a Liopleurodon or pliosaur?

It is from the Lower Oxford Clay

about 160myo

from the Callovian Jurassic era

Must Farm Whittlesey

Cambs. UK

Please ask if more info is needed

I will post a new fossil soon

Thanks!!!!

Gabriel

[Ash]

I cant help you, but anything for size?

Someone proper should be here to ID soon enough

Welcome to the forum btw! :

[Taogan]

It is probably crocodile, but we need a scale and a clear view of any curve visible (pliosaur teeth are curved)

[Pliosaur]

Hi,

Thanks, this is my first time

The tooth is generally very small.

It is about 13mm

the tip of the tooth is broken

side view

I can post more photos if you need

[Taogan]

I think I can see the start of the curve so it is a small pliosaur tooth, can't work out the species though.

[Pliosaur]

Thanks Taogan!!! Any other help would also be appreciated!!!

Thanks everyone!

[DE&i]

As Taogan suggests it would appear to be from a Pliosaur perhaps a posterior tooth . It has some really nice striations and enamelling.

I've seen Liopleurodon ferox and Peloneustes philarchus teeth from that area.

Regards,

Darren.

[Pliosaur]

Thanks,DarrenElliot

I appreciate your help!!!

[Pliosaur]

Anyone know the species??? what do Liopleurodon teeth have? Striations?

[pachy-pleuro-whatnot-odon]

Have a look at the below two posts, which might be informative as to how  to identify pliosaur species by their teeth:

 

 

 

Generally a good starting point would be Tarlo's (1960) review of Upper Jurassic pliosaurs, from which the below illustration was reproduced:

 

 

(B) Simolestes vorax, (C) Liopleurodon ferox, (D) Liopleurodon pachydeirus, (E) Pliosaurus andrewsi, and (F) Peloneustes philarchus. (A) was originally Simolestes nowackianus, but has since been reassigned as the machimosaurid (thus teleosaurid) Machimosaurus nowackianus.

 

From what I can see from the pattern of striations on your tooth, though, I'd say it looks very similar to mine from the Bathonian-state in the Ardley Quarry below, which I have currently written down as Peloneustes philarchus for the ring of short striations at the base interspersing the longer ones around the rest of the tooth.

[RuMert]

Heh, Alexander, it was a very old post @pachy-pleuro-whatnot-odon

Better try your skills on my Volga river tooth, I believe it's a Kimmeridgian pliosaur. 3 cm long, the preservation is not the best, it seems to lack enamel on half the surface. It doesn't look to exactly match any of the pics above. Some photos from side to side:

 

[pachy-pleuro-whatnot-odon]

2 hours ago, RuMert said:

Heh, Alexander, it was a very old post @pachy-pleuro-whatnot-odon

Better try your skills on my Volga river tooth, I believe it's a Kimmeridgian pliosaur. 3 cm long, the preservation is not the best, it seems to lack enamel on half the surface. It doesn't look to exactly match any of the pics above. Some photos from side to side:

 

 

Hahahah, you're totally right, Yury! However, I just couldn't resist the similarities between the tooth in this post and my own

 

Anyway, impressive tooth you've got there - even if a bit worn!

 

No doubt about this being a pliosaur, though which might indeed be difficult to establish due to the missing enamel. Complicating matters is that Tarlo (1960) only describes tooth morphologies for Oxfordian pliosaurs, and I myself don't really have any reference material for Kimmerdgian pliosaurs. Sassoon, Foffa and Marek (2015), however, note in their Table 1 (reproduced below) that the teeth of Kimmeridgian pliosaurs are either fully trihedral or subtrihedral, much like the specimen below from the Kimmeridge Clay of Oxfordshire (including Makhaira rossica from western Russia). That having been said, I have no idea how the teeth of Stretosaurus or Pliosaurus rossicus look - though from photographs online the latter also had (sub)trihedral teeth.

 

 

 

My first question to you would therefore be whether your tooth has a trihedral/triangular cross-section, which it doesn't quite seem to have. If not, my second question would be whether it is at all possible that the tooth could have washed in from nearby Oxfordian or Cretaceous sediments. From what I picked up from your descriptions of the Volga, the former doesn't seem likely, but may be the latter could be the case? In that case, the tooth could be brachauchenine - or, what used to be called,  Polyptychodon sp.. I think this is the most likely scenario. However, why I've still considered an Oxfordian-stage pliosaur is because the striae seem rather coarse with part of the tooth (first photograph) appearing clear of striae. This, together with the fact that some striations continue far above the rest - and may, in fact, have, originally, even reached the tooth apex - would make the tooth a close match for Liopleurodon ferox.

[RuMert]

Thanks for traditionally comprehensive analysis

P.rossicus had fully trihedral teeth - in fact I examined the holotype in the PIN museum once again a month ago and it's 100% trihedral (it comes from mid-Volgian/Tithonian). As I know Pliosauridae evolved trihedral teeth sometime in the Kimmeridgian, but it didn't help much - their biodiversity declined. So all Volgian (Tithonian) pliosaurs here have trihedral teeth and are attributed to the Pliosaurus genus, while Callovian ones with round teeth - to either Liopleurodon, Pelounestes or Simolestes. Oxfordian and Kimmeridgian sediments in central Russia are weak and rare - especially the latter, while Callovian and Volgian are abundant. Even though Kimmeridgian is widely represented in my Volga site, it's understudied due to bad preservation and fragmentary nature of ammonite and marine reptile remains while in the local Volgian they did find lots of associated bones and semi-complete skeletons. So basically everybody has a very vague idea of what was in the Russian Kimmeridgian reptile-wise.

I'm 90% sure the tooth comes from Kimmerigian - upper, which is more likely and found in the local cliffs, or lower which is also possible (I did find lower Kimmeridgian ammonites and even Callovian ones, but they are rare compared to upper Kimmeridgian Aspidoceras&Co - these sediments are under the water level). But I haven't seen there any Oxfordian Amoeboceras which I'm quite familiar with and some of them are soaking in my sink at this very moment. My thought is that Liopleurodon and Simolestes survived into the Kimmeridgian and the tooth must be theirs, but the species (or maybe local subspecies) is to be determined

[pachy-pleuro-whatnot-odon]

2 hours ago, RuMert said:

Thanks for traditionally comprehensive analysis

P.rossicus had fully trihedral teeth - in fact I examined the holotype in the PIN museum once again a month ago and it's 100% trihedral (it comes from mid-Volgian/Tithonian). As I know Pliosauridae evolved trihedral teeth sometime in the Kimmeridgian, but it didn't help much - their biodiversity declined. So all Volgian (Tithonian) pliosaurs here have trihedral teeth and are attributed to the Pliosaurus genus, while Callovian ones with round teeth - to either Liopleurodon, Pelounestes or Simolestes. Oxfordian and Kimmeridgian sediments in central Russia are weak and rare - especially the latter, while Callovian and Volgian are abundant. Even though Kimmeridgian is widely represented in my Volga site, it's understudied due to bad preservation and fragmentary nature of ammonite and marine reptile remains while in the local Volgian they did find lots of associated bones and semi-complete skeletons. So basically everybody has a very vague idea of what was in the Russian Kimmeridgian reptile-wise.

I'm 90% sure the tooth comes from Kimmerigian - upper, which is more likely and found in the local cliffs, or lower which is also possible (I did find lower Kimmeridgian ammonites and even Callovian ones, but they are rare compared to upper Kimmeridgian Aspidoceras&Co - these sediments are under the water level). But I haven't seen there any Oxfordian Amoeboceras which I'm quite familiar with and some of them are soaking in my sink at this very moment. My thought is that Liopleurodon and Simolestes survived into the Kimmeridgian and the tooth must be theirs, but the species (or maybe local subspecies) is to be determined

 

It's possible that Liopleurodon - which I think this tooth most resembles, as Simolestes had more gracile striae - survived into the Kimmeridgian. But as there are Callovian exposures in the area, I wouldn't want to exclude the tooth coming from below the water level - though chances are slim, I'll give you that. However, unless further evidence of pliosaur survival comes to light, or you found this tooth in the cliffs in unpertubated deposits (i.e., not reworked), I'd say that, according to Occam's Razor, this being a Callovian Liopleurodon ferox is the simplest explanation.

 

That having been said, I did at one point buy a small partial pliosaur tooth from the Boulonnais that is said to have come from the Tithonian. It's round too, and looks strikingly like what would be identified as Liopleurodon ferox, if not for its dating... Interestingly, however, it was found near where the Liopleurodon ferox holotype-specimen was found.

[RuMert]

12 hours ago, pachy-pleuro-whatnot-odon said:

I'd say that, according to Occam's Razor, this being a Callovian Liopleurodon ferox is the simplest explanation.

 

Maybe you are right, but there are too few Callovian outcrops in the area. Ammonites and the tooth were found in quite a distance from each other. Occam's Razor in this case IMHO leans towards the Kimmeridgian: lots of outcrops, scarcity of pliosaur material, especially teeth to guarantee absence of a species in a time period, not a big time difference (Oxfordian-Kimmeridgian). I'm not a fan of either theory and happy enough with what I have, but your post raised an interesting question: when exactly is the border between circular and trihedral teeth in pliosaurs. A few arguments in favor of Kimmeridgian Liopleurodons:

1. Tarlo's  book was written in 1960, lots of new material found since;

2. Time difference is negligible, we are not discussing Pliocene pliosaurs and the Loch Ness monster;

3. Even with big time difference there are lots of species that outlive their time period: horseshoe crabs, chimaeras, nautilus, latimeria and a zillion others;

4. Some time of Liopleurodon and Pliosaurus coexistence is garanteed, I'm sure several pliosaur genera and dozens of species were present at the same time;

5. Kimmeridge clay fm mostly starts from the Upper Kimmeridgian (Dorset and such) with a weak lower one, so Kimmeridge clay founds may not reflect Lower Kimmeridgian fully;

6. Skulls and teeth are rare and many pliosaurs known by postcranial bones could have "unusual" teeth;

7. Overall pliosaur material is scarce and the research is far from established: genera, species and their features are attributed and reattributed constantly. I'd say today we know pliosaurs less than ancient Egyptians knew astronomy.

BTW a couple of papers for consideration: Mexican Kimmeridgian Liopleurodon and German Cretaceous Simolestes

 

 

 

[pachy-pleuro-whatnot-odon]

1 hour ago, RuMert said:

BTW a couple of papers for consideration: Mexican Kimmeridgian Liopleurodon and German Cretaceous Simolestes

Those look like very interesting articles! If their findings are indeed correct, this would completely change what we know about pliosaur evolution and diversity! I mean, of course it's strange that you've got round teeth prior to the Kimmeridgian (Callovian and Oxfordian) and round teeth again after (in the Cretaceous), but would only have trihedral teeth in the interim. And, sure, the Kimmeridgian is a little-studied time-interval. But the paucity of reported rounded pliosaur teeth from the Kimmeridgian is striking. I emphasise reported, as it may well be that, rare as they are, rounded pliosaur teeth are being found from the Kimmeridgian, but are simply not finding their way into scientific literature. In light thereof, some photographs of the Liopleurodon tooth from the Boulonnais I mentioned before:

 

 

 

Compare to the below the Liopleurodon ferox tooth from Hildesheim in Germany, described by Sven Sachs: , describ

 

Or to this tooth, also identified as L. ferox and said to come from Oxford Clay of Peterborough:

 

 

Please note, though, that plesiosaurian teeth with this morphology have been around from the very earliest Jurassic, if not the last stages of the Triassic, by way of rhomaleosaurid plesiosaurs:

 

 

 

 

 

As such, one explanation for this morphology appearing beyond the Oxfordian might be that this was evolutionarily just a very successful tooth-type for predators - not necessarily because Liopleurodon sp. survived.

 

2 hours ago, RuMert said:

Maybe you are right, but there are too few Callovian outcrops in the area. Ammonites and the tooth were found in quite a distance from each other. Occam's Razor in this case IMHO leans towards the Kimmeridgian: lots of outcrops, scarcity of pliosaur material, especially teeth to guarantee absence of a species in a time period, not a big time difference (Oxfordian-Kimmeridgian). I'm not a fan of either theory and happy enough with what I have, but your post raised an interesting question: when exactly is the border between circular and trihedral teeth in pliosaurs. A few arguments in favor of Kimmeridgian Liopleurodons:

1. Tarlo's  book was written in 1960, lots of new material found since;

2. Time difference is negligible, we are not discussing Pliocene pliosaurs and the Loch Ness monster;

3. Even with big time difference there are lots of species that outlive their time period: horseshoe crabs, chimaeras, nautilus, latimeria and a zillion others;

4. Some time of Liopleurodon and Pliosaurus coexistence is garanteed, I'm sure several pliosaur genera and dozens of species were present at the same time;

5. Kimmeridge clay fm mostly starts from the Upper Kimmeridgian (Dorset and such) with a weak lower one, so Kimmeridge clay founds may not reflect Lower Kimmeridgian fully;

6. Skulls and teeth are rare and many pliosaurs known by postcranial bones could have "unusual" teeth;

7. Overall pliosaur material is scarce and the research is far from established: genera, species and their features are attributed and reattributed constantly. I'd say today we know pliosaurs less than ancient Egyptians knew astronomy.

 

But you may be right in that 1) as the Kimmerdigian is still mostly unknown - and what is known off it mainly derives from a single part of the world; 2) Tarlo's work hasn't been updated in over 60 years; 3) and pliosaurian remains are generally scarce to the point that it takes a long time to uncover convincing evidence for their presence and evolution, we may simply be unaware of certain species of pliosaur - including survival of certain other ones. It's certainly conceivable that the (pliosaur) biota in the UK changed around the Kimmeridgian, but that the pliosaur lineages that previously lived there continued in other places around the world...

[RuMert]

I think I found the answer to trihedral tooth type timeline: from the paper you cited P.kevani was characterized by subtrihedral teeth while later species - by fully trihedral. So this form probably "a vu le jour" during the Mutabilis ammonite zone (Upper Kimmeridgian, 152 ma).

54 minutes ago, pachy-pleuro-whatnot-odon said:

strange that you've got round teeth prior to the Kimmeridgian (Callovian and Oxfordian) and round teeth again after (in the Cretaceous), but would only have trihedral teeth in the interim

Pliosauridae probably evolved this tooth type either as an evolutionary "test" or to counter some qualities of their prey (thick skin?). I don't think it contributed to their demise but didn't help either. So with no unequivocally positive results this feature was dropped later.

 

54 minutes ago, pachy-pleuro-whatnot-odon said:

some photographs of the Liopleurodon tooth from the Boulonnais I mentioned before

Very nice tooth you got there! Good preservation of the base with all striations visible

 

54 minutes ago, pachy-pleuro-whatnot-odon said:

plesiosaurian teeth with this morphology have been around from the very earliest Jurassic

BTW do you happen to have comparative pictures of Simolestes/Peloneustes/Liopleurodon teeth? Those written descriptions are not too illustrative

 

[paulgdls]

Well, Steve Etches has seen conical pliosaur teeth from the lower Kimmeridgian of Abingdon UK. They are in a private collection. Apart from that, I'm not aware of a similar occurrence but I'd have thought its very likely that pliosaurs other than Pliosaurus survived into the Kimmeridgian.

 

Liopleurodon:

 

 

Simolestes:

 

 

Peloneustes:

 

[RuMert]

Thank you, very interesting pictures

[RuMert]

@paulgdls, @pachy-pleuro-whatnot-odon, @PointyKnight

What do you think about these teeth? Pliosaur teeth are very rare here, any thoughts would be valuable

 

1. This tooth was IDed as Liopleurodon ferox. Comes from Callovian. All the teeth below are from Callovian (Ryazan, Kostroma, Saratov)

 

2. This was IDed as Simolestes

 

3. This was probably not IDed at all

 

4. Simolestes sp.

 

5. Simolestes sp.

[pachy-pleuro-whatnot-odon]

54 minutes ago, paulgdls said:

Well, Steve Etches has seen conical pliosaur teeth from the lower Kimmeridgian of Abingdon UK. They are in a private collection. Apart from that, I'm not aware of a similar occurrence but I'd have thought its very likely that pliosaurs other than Pliosaurus survived into the Kimmeridgian.

 

1 hour ago, RuMert said:

Pliosauridae probably evolved this tooth type either as an evolutionary "test" or to counter some qualities of their prey (thick skin?). I don't think it contributed to their demise but didn't help either. So with no unequivocally positive results this feature was dropped later.

 

Indeed, I can't quite see the only genus of pliosaur surviving into the Kimmeridgian being Pliosaurus, seeing, as mentioned, the conical teeth return. I don't think it likely this would be a reversal of a trait developed in the Kimmeridgian (teeth being subtrihedral) either, as this is not the way evolution works. That is, the teeth of Pliosaurus either became subtrihedral due to selective pressures or as a neutral mutation. If, however, they were a neutral mutation, then there'd not necessarily be any pressure to revert them to conical teeth, and the chances of this happening would be just as slim as subtrihedral teeth originating in the first place. As subtrihedral teeth may indeed have developed further into fully trihedral teeth, it seems likely, though, that there was a selective advantage to this tooth-morphology. This being the case, a development like this would not likely be lost in the way these teeth seem to disappear in the Cretaceous. That is, the same principles of evolution would apply, so that either you'd see a gradual devolution back to conical teeth, or a totally unrelated shape change if this were a new and different neutral mutation. As conical teeth clearly existed during the Cretaceous, however, it seems much more reasonable to assume certain pliosaur-species with conical teeth managed to persist into the Cretaceous, even if not yet found.

[paulgdls]

1 hour ago, RuMert said:

@paulgdls, @pachy-pleuro-whatnot-odon, @PointyKnight

What do you think about these teeth? Pliosaur teeth are very rare here, any thoughts would be valuable

 

1. This tooth was IDed as Liopleurodon ferox. Comes from Callovian. All the teeth below are from Callovian (Ryazan, Kostroma, Saratov)

 

2. This was IDed as Simolestes

 

3. This was probably not IDed at all

 

4. Simolestes sp.

 

5. Simolestes sp.

 

Well. I'm gobsmacked about that first tooth. Is that in your collection? The enamel appears to be about 5.5 to 6 inches long, which would make the total length with root 18 inches plus. Skull length 3m plus if Liopleurodon.  This is larger than the largest tooth in the Leeds collection at the NHM (length on the mid line 14.75 inches). Also the coarseness and spacing of the ridges is amazing. Certainly very coarse for Liopleurodon as described by Lesley Noe et al. Pachycostasaurus dawni has similarly coarse ridges and spacing but I believe only one specimen has ever been found and that is much smaller. 

 

I'll look at the others later.

 

Paul

 

[DE&i]

A few photos of Liopleurodon ferox teeth.

 

 

And a small Simolestes tooth from the Oxford Clay of Peterborough if it helps. 

 

[paulgdls]

Hi Darren

 

Brilliant photos! Thanks for posting.

 

Paul

 

 

[RuMert]

@DE&i Thanks for the photos!

 

On 3/5/2021 at 8:45 PM, paulgdls said:

Is that in your collection?

 

Unfortunately not These are some of the better pliosaur teeth collected in Russia recently, at least those known to the public. Basically there are 3 sources of Jurassic marine reptile material here: the best was obtained in the Volga region shale mines, including P.rossicus and P.irgisensis. Now the mines are closed, they are not profitable enough. Secondly there are river sites (on the Volga again, like the one in my signature), I know 4 of them, but they are poorer than Yorkshire and Dorset: they produce deep sea mostly fragmentary material, not tourists' attractions but mostly country places for vacationers and country people with simple interests (thus not so much labor invested in collecting). Few specialists hunt there for mostly ammonites (and they prefer Volgian and Hauterivian sections due to better preservation and articulation). Finally reptile remains can rarely be found anywhere: quarries, river banks, known small sites (I found an ichthyosaur tooth in Moscow for example) but they are extremely scarce. Thus we don't have this amount of material as in the UK and consequently lack proper ID skills. For example I still can't see real difference between the 1st and the last teeth DE&i posted (great specimens for sure). They both have rare ridges, looking delicate enough.

 

P.S. another pic of the tooth above