A gigantic foot from the Morrison formation

[Halichoeres]

A huge hind foot from Wyoming's section of the Morrison formation has been identified as a brachiosaurid. I didn't know this, but there wasn't any brachiosaurid hind foot material known from Late Jurassic North America before this.

Feet are complicated:



Paper is open access: https://peerj.com/articles/5250/

And here's a short write-up in Gizmodo: https://gizmodo.com/giant-dinosaur-foot-identified-20-years-after-being-une-1827813723

[Simon]

You beat me to it, Halichoeres!!! 

This is the largest sauropod foot found anywhere (over a METER wide), hence this Brachiosaur must have REALLY been a GIANT.

Related to Sauroposeidon, I wonder?  I'm curious to see estimates of this critter's total size.  The super-max Titanosaurs of the Late Cretaceous have just got themselves a true competitor.  A Brachiosaur of this size could have been just as large as any of those!!!

Here's another article on the find:

https://phys.org/news/2018-07-paleontologists-largest-dinosaur-foot-date.html

[Neosodon]

Don't mean to dampen the excitement but they said it wasn't near as large as the largest titanosaurs. "Plus, as Mannion and the study authors point out, we've never found the feet of the world's largest sauropods, the titanosaur and argentinosaurus, who would surely surpass this brachiosaur in foot size." But as it is the largest sauropod foot found and in well preserved condition its no less exiting. It's also cool to know that sauropods were so well spread.

[Newt]

There's a passage in the paper estimating the animal's total size using Sonorasaurus (a brachiosaurid with both pedal and leg remains) as a proxy; it ends up being very close to, but slightly larger than, the type specimen of Brachiosaurus altithorax. So, not a longkosaur-sized supergiant, but still a mighty impressive beast, and probably the heaviest Morrison sauropod specimen known (with the possible exception of A. fragillimus).

[Vidusaurus]

Very interesting find! Curious that it was found isolated from all other parts of the skeleton - could have been trapped in quicksand/tar like at the Cleveland-Lloyd Dinosaur Quarry?

it ends up being very close to, but slightly larger than, the type specimen of Brachiosaurus altithorax. So, not a longkosaur-sized supergiant, but still a mighty impressive beast

What is the probability that it is a new species, I wonder? Seems more likely that it was just a large Brachiosaurus altithorax (or that B. altithorax was just a huge chunker with massive hind feet).

[Newt]

I think the chances that it is B. altithorax are very good, but the authors are being properly cautious and not assigning it to a known taxon with no overlapping material - just as with the Felch Quarry skull (USNM 5730). This skull looks pretty similar to the well-known skull material of Giraffatitan brancai and so is very likely from B. altithorax, but it's impossible to be certain until a specimen, or series of specimens, with material overlapping both the holotype and these fragmentary remains is discovered. Morrison brachiosaur remains are unfortunately rare.