The history of Supersaurus — and its buddies Ultrasauros and Dystylosaurus — is pretty complicated, and there seems to be no one source for it. But having read a lot about these animals in the process of writing eleven mostly pretty substantial posts about them, I feel like I’m starting to put it all together.

I keep wishing there was a single place out there where I could look up Jensen’s old BYU specimen numbers for Supersaurus , Ultrasaurus and Dystylosaurus elements, and find the modern equivalents, or vice versa. Then I realised there’s no reason not to just make one. So here goes! The first column shows the specimen numbers as used in Jensen (1985), and last column contains Jensen’s own assignments except where noted.

Poor Dystylosaurus . Always the bridesmaid. No-one seems to care much about it, yet the one and only vertebra that bears that name is the single most diagnostic elements out of all the individual bones that have been assigned to Supersaurus over the years.

Since the previous installment of this epic, we’ve taken two brief digressions on how little importance we should attach the colours of bones in our photographs when trying to determine whether they’re from the same individual: cameras do lie, and in any case different bones of the same individual can age differently.

Having surveyed what we know from the published literature about Jensen’s Big Three sauropods, and what Matt and I concluded about its big cervical BYU 9024, and having thought a bit more about the size of the BYU 9024 animal, we’re getting to the point where we can consider what all this means for Jensen’s taxa.

Now considered a junior synonym of Supersaurus , on very solid grounds. Incidentally, unlike the neural spines of most non-titanosaurian sauropods, the neural spine of this vertebra is not simply a set of intersecting plates of bone. It is hollow and has a central chamber, presumably pneumatic.