Madagascar Dinosaur Vertebra?

[Crazyhen]

Any idea if this bone is a dinosaur vertebra?  It is from Madagascar but unfortunately no further information as to its exact locality/formation.  The seller said the nerves are also preserved, is that so?

[DinoFossilsUK]

I'm not the best qualified to help as I'm not very familiar with Madagascan dinos, but seeing as no one else has answered yet I'd hazard a guess that it's sauropod (due to the shape/size).   Definitely dino, but if they don't know the provenance I doubt you're going to be able to ID it beyond sauropod.  And I'd ignore the stuff about "nerves" 

[Troodon]

Agree its a dorsal vertebra from a sauropod with that large pneumatic fossa.  Lots of Jurassic sauropod in the Isalo III fm if its Jurassic and others in the late cretaceous Maevarano Formation like the one from the figure I added.  So an ID is impossible without a provenance.  Also their sauropods are very poorly understood and an ID may be not possible.  Has far as the nerves still preserved your seller must be smoking something that is causing hallucations

 

Kristina Curry Rogers (2009) The postcranial osteology of Rapetosaurus krausei (Sauropoda: Titanosauria)
from the Late Cretaceous of Madagascar, Journal of Vertebrate Paleontology, 29:4, 1046-1086, DOI: 10.1671/039.029.0432

 

 

[Troodon]

Lots of Madagascar material is finding its way to China.  This material must have a provenance to try to identify.  Most material comes from exposures In the Mahajanga basin and as you can see in the attached figure the age can be very widespread so just identifying it as being from Madagascar  is not adequate 

[Crazyhen]

Yes, a lot of fossils like dinosaur bones and ammonites as well as minerals are imported into China.  For fossils, because of the national fossil law, the imported fossils must not be in raw form, and so most are polished/craved into products (e.g. polished ammonites, cigarette tray, massage balls).  Occasionally we could find raw bones like the one above, they are believed to be mixed with polished/finished fossils when being imported.

 

Provenance is normally not known as the fossils/products are imported in large shipment, presumably of mixed sources from Madagascar and nobody really cares about where exactly does a bone come from.

[pachy-pleuro-whatnot-odon]

It has been said before, but I agree this is a sauropod vertebra, based on morphology and size, I'd say likely from a titanosaur. According to this list on Wikipedia, two genera, each containing a single species, are know from Madagascar: Rapetosaurus krausei and Vahiny depereti. Both are titanosaurs and both occur in the Late Cretaceous deposits of Maeverano Formation of the Mahajanga Basin. However, R. krausei seems to be the better known, and I was only able to find one publication on V. depereti: Rogers & Wilson (2012), providing a systematic description based on its braincase. In addition, I found this quote online:

 

Quote

Finally, after going through Rapetosaurus krausei and "Titanosaurus" madagascariensis, we get to the *other*, other Maevarano titanosaur. The short story is that a small amount of the Maevarano titanosaur material, less than 10% of the vertebrae, limb bones, and girdle bones, represents something other than R. krausei (Curry Rogers and Wilson 2014). For a little over a decade, this taxon was known informally as Malagasy Taxon B. As was explained with "T." madagascariensis, you might think that Taxon B should be some new genus using madagascariensis, but that is not how things have worked out. On the one hand, Vahiny depereti could be construed as an overabundance of taxonomic caution.

 

It thus seems that the more likely candidate for the above vertebra would be Rapetosaurus krausei. For what it's worth, though, here's another titanosaur vertebra from Madagascar that may be attributed to V. depereti, but that seems to match the above vertebra less than R. krausei (source: ibid.).

 

 

When looking for information on Madagascan marine reptiles, I ran into this site containing the theses from all Malagasy universities combined. Though in French, somewhat tricky to search, and combining work in different fields, it contains a wealth of up-to-date and possibly as yet unpublished data that may help you find out more about this particular specimen. Two theses I've managed to find that make mention of R. krausei, for instance, are 1 and 2.

 

Hope this helps!