Cetiosaur?

[fossil_sea_urchin]

For some reason there are lots of "Duriatitan" fossils for sale from Oxforshire. But Duriatitan is only known from a large leg bone from Dorset. This vert is described as Duriatitan from Oxfordshire, it can't be that so what is it? 

[Troodon]

A dealer at the Tucson show had quite a few for sale and said his research pointed him to Duriatitan but there is little scientific data to support that assignment like you pointed out but I do not know since I have done little research myself.  You should ask him and see what he says.  Could it be Cetiosaur yes and we have more information on that species but you really need a sauropod expert to properly ID this vert,  if its possible.  I liked his offering and bought one and have labeled it Eusauropoda indet.  Its a cool rare add to any collection so if you like it buy it and an ID can be sought afterwards.

Paper on Cetiosaur "A" has some resemblance

https://www.tandfonline.com/doi/abs/10.1671/0272-4634(2003)23[208%3ATAATOC]2.0.CO%3B2

 

[gigantoraptor]

These are the caudal vertebrae of the holotype of  Cetiosaurus oxoniensis. this species is now considered the type species instead of C. medius.

They look similar but are not quite the same.

 

[Anomotodon]

Duriatitan was found in the Kimmeridge clay formation of Dorset, yes, but deposits in Abingdon are of the same age. So Duriatitan is a possibility for this vert, but there could have been other Macronarian sauropods, so Eusauropoda indet. is definitely the most accurate ID. Cetiosauridae is much less likely since most of the species of this family are much older, Middle Jurassic and the morphology doesn't really match.

[pachy-pleuro-whatnot-odon]

I don't know... This still very much looks like a plesiosaur vertebra to me: the vertebra seems too rounded and heart-shaped compared to the sauropod vertebrae I've seen; the specimen appears rather short and lacks the strong lengthwise constriction of the vertebral body typically seen on sauropod vertebrae; and the medioanterior depressions on the neural arch remind me of similar structures on plesiosaurian vertebrae (though I suspect they may be present in other clades less familiar to me as well). However, I guess that one of the most telling features has not been illustrated in the photographs: the presence, distribution or absence of subcentral foramina...

 

In any case, Frank's post below might be informative here as well.

 

 

 

[paulgdls]

The kimmeridgian of Abingdon, Oxfordshire is a marine deposit and hence the vast majority of vertebrate fossils found there are those of marine reptiles. As @pachy-pleuro-whatnot-odon says can we have a photo of the ventral side to see if there are paired foramina present? 

[DE&i]

Would you say @fossil_sea_urchin vertebra looks dorsal in appearance @paulgdls I just had a look at an old find of mine obviously more elongated. 

Edited March 20, 2021 by DE&i

[pachy-pleuro-whatnot-odon]

Wow,  what a beautiful vertebra! Is that the same one you pulled out of the clay in the other pictures?

 

Anyway, looks like one of the very last pectorals crossing over into the first dorsals to me (the position of the rib attachment sites is determinative). Take a look at the below diagram that I like to use as a reference (from Noè, Taylor and Goméz-Peréz [2017]):

 

[DE&i]

Possibly either one or the other, this vertebra is from the Oxford Clay. 

[pachy-pleuro-whatnot-odon]

1 hour ago, DE&i said:

Possibly either one or the other, this vertebra is from the Oxford Clay. 

 

As the spinal column is a graded continuum, such questions, I believe, are inherently difficult to answer, other than by conventionalized categorization. Unfortunately, I'm not familiar with these subdivisions in sauropterygians, having received my main anatomical education with reference to mammals. In mammals, the number of cervical vertebra is standardized at seven, for example. But these divisions may be species, genus or clade-specific in sauropterygians, as these are deviations from the standard vertebral formula in mammals as well.

 

However, when looking at the above diagram, your vertebra seems to fall into the category described as E by the authors. As can also be seen from the same image, this does not correspond one-on-one to pectoral vertebrae, however, with the very last vertebra(e) of E falling within the dorsal section of the spinal column. While dorsal vertebrae can normally be distinguished from non-dorsals for the fact that the rib attachments are located on the neural arch, some of them also exhibit the transgression of rib attachments. This is the case with yours, I believe. I'd therefore call it dorsal.

[DE&i]

Is the vertebrae considered a pectoral if any part of the rib facet is in contact to the centrum. Would you say this could be unclear, as in some there is contact on one side but not the other.

[paulgdls]

Lovely vertebra Darren, one of the best having no crushing (also, I agree, it looks similar to the vertebra which is the subject of this thread). I agree, yes, rib facet in contact with centrum = pectoral. If one side is in contact and the other not it could be called transitional or pectoral/dorsal I guess.