Angistorhinus: Triassic Phytosaur on Display
Nosin’ Around!
This is the closest I have been to #Angistorhinus. It is on display at the amazing St. George Dinosaur Discovery Site at Johnson Farm in Utah. I am rapidly becoming enamored with these amazing critters. Their skulls are gorgeous!
When I think Wyoming, I think Jurassic (#sauropod #dinosaurs of course :-)). I certainly don’t think of the Triassic. Those few times I do think about the Triassic I think of Arizona’s Petrified Forest. Yet Williston collected material from the Popo Agie River (and Formation) that Maurice Mehl named in 1913 as Anghistorhinus grandis.
Alas, no etymology is provided, my best guess is the name means “narrow snout,” based on its tweezer-like front end. The species name refers to its huge size, at over 24’ long, it is larger than any living #crocodile.
Check out that nose, right above and slightly in front of the eyes. I suppose that keeps the nose safe from struggling prey. As a #Phytosaur, it is an example of convergent evolution, that long teeth-ladened snout is superficially similar to gharials of today, but it isn’t related to them at all other than being #reptiles.
The teeth suggest it ate mostly fish, but at its size, it could have munched on anything living at the time, around 225 mya, one of the oldest of the #phytosaurs.
I was surprised when Mehl wrote, “Another specimen of Angistorhinus is represented by a skull, the mandible, and apparently a nearly complete skeleton.” Nearly complete skeleton???
The A. grandis holotype had a few postcranial elements possibly belonging with the skull. Why didn’t he describe the other one? And what became of it? He even felt it was a new species of Angisto. My guess? It wasn’t as big, and the *est always wins out (longest, tallest, oldest, etc.est :-)).
I love reading these 100+ year-old papers as they are literally sorting the beasts out “in real time.” In this case, Mehl was able to change a character ascribed to all of #Phytosauria at the time, as this specimen ruined McGregor’s “parieto-squamosal arcade greatly reduced and depressed” by having it “well developed behind the posterior dorsal surface of the skull.”
#FossilCrates