Sauropod vertebra?

[FF7_Yuffie]

Any thoughts on this?

 

Being sold as sauropod cetiosaurus vertebra from Kimmeridge Clay. 11cm x 12 x 5.5

 

The hole at the bottom, seller says is predation from a scavenger -- size and shape matching croc or pliosaur.

 

I'm suspecting plesiosaur, looking at a drawing of cetiosaur verts I found online. This one seems too rounded.

 

Any thoughts, much appreciated. Attached the drawing below too.

[JohnJ]

Regardless of the what this vertebra belonged to, it is unrealistically presumptuous to assign any type animal as creating the hole in the eroded bone.  Think about it; what kind of objective evidence is there that rules out one 'hole maker' over another?  The hole could be unrelated to scavenging.

[Kikokuryu]

I did see this vert and a few others earlier today as well. So, the provenance for this may or may not be an issue in terms of being dinosaurian. I purchased a vertebra (sold as Dacentrurus) from the same seller, but I am fully prepared of it not being dinosaurian given that it and the "sauropod" vert the OP is inquiring about comes from the gravel pits in Oday Common, Abingdon which seems to not contain Kimmeridge Clay dinosaurs as far as I've been searching around. Apparently most of this is misidentified Pliosaur verts?

 

These aren't really super expensive so I wasn't expecting a positive ID and was a purely an impulse buy. But is it almost certain that dinosaurs don't come out of Abingdon, or is it still debated?

[Kosmoceras]

8 hours ago, Kikokuryu said:

I did see this vert and a few others earlier today as well. So, the provenance for this may or may not be an issue in terms of being dinosaurian. I purchased a vertebra (sold as Dacentrurus) from the same seller, but I am fully prepared of it not being dinosaurian given that it and the "sauropod" vert the OP is inquiring about comes from the gravel pits in Oday Common, Abingdon which seems to not contain Kimmeridge Clay dinosaurs as far as I've been searching around. Apparently most of this is misidentified Pliosaur verts?

 

These aren't really super expensive so I wasn't expecting a positive ID and was a purely an impulse buy. But is it almost certain that dinosaurs don't come out of Abingdon, or is it still debated?

 

You certainly can get dinosaur bones from the Kimmeridge Clay around Oxford (see here: https://www.palass.org/publications/palaeontology-journal/archive/23/2/article_pp411-443). You are right though that they are turning up on dealers’ sites with increased frequency, very often mistaken for plesiosaur vertebrae.

[FF7_Yuffie]

56 minutes ago, Kosmoceras said:

You certainly can get dinosaur bones from the Kimmeridge Clay around Oxford (see here: https://www.palass.org/publications/palaeontology-journal/archive/23/2/article_pp411-443). You are right though that they are turning up on dealers’ sites with increased frequency, very often mistaken for plesiosaur vertebrae.

 

This is what makes me so cautious from this location. I've posted a few here, and had a couple I've been interested in looked at elsewhere, which have turned out to be plesiosaur. It's a shame, I've been wanting a Sauropod vert for a while.

[pachy-pleuro-whatnot-odon]

It's hard to say with these vertebrae whether they might be dinosaurian in origin. In general, the material found at Oday is of marine origin, with a surprising amount of it being pliosaurian. In fact, pliosaurs and marine crocodiles are so common in the area that, puncture wounds in bones found here can, within a certain amount of reasonability, be attributed to either of these two big predators. To my knowledge, plesiosaurian plesiosaur and ichthyosaur remains are relatively less abundant in Oday, though still occur there. However, seeing as the marine fauna predominating here, finding any bit of dinosaur would be of uncommon occurrence (that being said, a lot of the French Jurassic coastal sites yield a surprising amount of verifiable sauropod material, enough to wonder whether sauropod remains might have for some reason been more likely to end up in a marine context).

 

Turning back to the vertebrae shown here then, what complicates attribution is that there is significant variation in the plesiosaurian and pliosaurian vertebrae found here, on the one hand, versus the poor state of preservation of the specimens themselves, on the other. That is, the vertebral centra of certain pliosaur species have bevelled edges, while in some species a groove demarcates the edge. In other species again, the edge shows certain rugose spots. It is difficult enough as it is to identify a certain species of pliosaur based on these characteristics (as they are, moreover, less diagnostic than skull-elements), let alone distinguish them from dinosaurian vertebra. Your best bet, therefore, would be to familiarise yourself with both sauropterygian and sauropod vertebra, so that you can compare characteristics on a vertebra versus those expected for either group. Although I'm not versed in dinosaur bones at all, I can imagine we might be able to use the below characteristics:

1. Does the vertebra have ventral and, optionally, dorsal foramina? This is an indication of the specialised vascular system of sauropterygians, and would point to the vertebra being a plesiosaurian or pliosaurian one.
2. Does the vertebra have a notochordal pit in the middle (presence of mamilla not relevant)? Then it's most likely a pliosaur vertebra.
3. Does the vertebra have a ventral keel? Do sauropods have these, as certain plesiosaurs (sensu lato) certainly do? If not, this could be a way to distinguish the two.
4. Does the vertebra have a ventral lip rather than a keel? If so, your vertebra is a pliosaurian one.
5. Shape of the vertebral body: plesiosaurs (sensu stricto) have a somewhat heart-shaped centrum, while that of pliosaurs is rounded on the axial plane. From the drawing above, it looks like sauropod centra are square...
6. Does the vertebral centrum constrict medially, causing the centrum's facets to project and form a bevel around the centrum? If so, likely not a sauropterygian vertebra.
7. Is the neural arch attached to the vertebral body or does the vertebral body only have facets the neural arch would have sat upon? Is the division between neural arch and vertebral body marked by visible suture lines? If either of the two is true (so a suture line is present or only facets can be seen where the neural arch would go), the vertebra is likely that of a pliosaur and not a plesiosaur (s.s.). Not sure how this compares to sauropods, though.

 

If we look at the posted vertebra, starting with the second, the position of the lateral processes inform us that this is a posterior cervical vertebra. The centrum's facets are rounded, with possible traces of a notochordal pit in the middle. Though the neural arch is attached, it looks like a suture line may be present. There's no clearly marked marginal bevel and presence or absence of ventral features cannot be determined. Based on this, my best guess at this point in time is that the vertebra belongs to Pliosaurus macromerus.

 

As to OP's vertebra: a notochordal pit is clearly present, the articular surface of the vertebral centrum being heart-shaped. There doesn't seem to be a ventral keel or lip, but the marginal bevels are much more pronounced than one would expect from a plesiosaur (s.l.). This is probably what the sauropod attribution stems from, yet is not unheard of in plesiosaurian (s.s.) vertebrae either. Features ventral to the vertebral centrum are hard to make out, but there do seem to be foramina present. The area around where the neural arch would've sat is hard to make out, but it appears that rather than facets, what's visible are the remains of the neural arch itself. I'd therefore say this is most likely a plesiosaurian vertebra, possibly with some pathological bone growth around the vertebral margins, rather than sauropod. That is, all images that I can find of sauropod vertebrae show them as being waisted, yet not with the rugose bevel on the vertebral "barrel", but, rather, on the articular surfaces.

Hope this helps!

[Troodon]

Buying centrums is a risky proposition since key diagnostic features can be missing and therefore misidentification can be high.   I DO NOT know who the owner of this centrum is but I'll throw this out to show a different point of view on why its difficult to make a call. 

 

If I just take a lateral view of this vertebra and compare it to the image provided of a Cetiosaur and one of a plesiosaur I see more of a relationship with the Cetiosaur.  The sharp corners and body of a Plesiosaur do not compare well with the one in question.  

 

 

A couple of Cetiosaurus vert photos provided by @Masp visit to Natural History Museum London demonstrates that they can be somewhat rounded probably dependent on position in the column.

 

[pachy-pleuro-whatnot-odon]

2 hours ago, Troodon said:

Buying centrums is a risky proposition since key diagnostic features can be missing and therefore misidentification can be high.   I DO NOT know who the owner of this centrum is but I'll throw this out to show a different point of view on why its difficult to make a call. 

 

If I just take a lateral view of this vertebra and compare it to the image provided of a Cetiosaur and one of a plesiosaur I see more of a relationship with the Cetiosaur.  The sharp corners and body of a Plesiosaur do not compare well with the one in question.  

 

 

A couple of Cetiosaurus verts provided by Masp vist to Natural History Museum London demonstrates that they can be somewhat rounded probably dependent on position in the column.

I agree, that's exactly what makes identification of these vertebrae so difficult. And you're right in that the OP's vertebra doesn't look like your typical plesiosaurian vertebra. As noted, I think it's exactly these marginal bevels that have led to its sauropod attribution. However, when I look at the position of this bevelling, it seems to me that this would only be at the very outermost edges of the vertebral "barrel" - that is, almost only an outward projection of the articular surface in a vertical direction, rather than the bevel extending inward into the rest of the vertebral body. Put differently, the positioning of the bevel in OP's vertebra is different from what - albeit after just a brief search - I would expect for a sauropod vertebra and is more similar to what I've seen on plesiosaurian vertebrae. But I concede that, though the likelihood of it being a plesiosaurian vertebrae is greater, it's hard to make this argument conclusively. Moreover, some key areas aren't properly illustrated by the photographs, which complicates something that would probably still remain difficult even holding the piece in hand, due to the poor preservation of the vertebra.

[FF7_Yuffie]

Thanks for the help @Troodon and @pachy-pleuro-whatnot-odon

 

Some great info here.  Some I need to look up because it went over my head  Seems like fossils from this area are difficult to get ID from with the worn condition. But thanks for taking a look at it both of you, appreciate it.

[DE&i]

I've found a few Pliosaur vertebrae from the Kimmeridge Clay a couple of year's ago. Would these photos help for comparison @FF7_Yuffie