Opisthocoely grading into amphiplatyan and
platycoelous vertebrae in *Opisthocoelicaudia* now no longer is so
"bizarre,"
Sort of makes you wonder why some folks (not many, mind you) are so dead-set
against putting _Opisthocoelicaudia_ in with the titanosaurs. It looks like
a bona fide titanosaur to me - and _Opisthocoelicaudia_ may one day prove to
be the same as _Nemegtosaurus_. (_N_. is known only from a skull, and _O_.
is known from a skeleton with the head and neck missing.) The presence of
opisthocoelous caudals in at least two titanosaurs (_Opisthocoelicaudia_,
_Rinconsaurus_) reinforces the point that titanosaur caudal vertebrae can
show considerable diversity in their combination of articular surfaces.
In any case, having opisthocoelous proximal caudals was never that bizarre,
considering that the posterior dorsals of derived titanosaurs are also
opisthocoelous.