Shop Mobile More Submit  Join Login


Submitted on
April 1, 2010
Image Size
4.9 MB


13,293 (10 today)
235 (who?)
Diversity of the Crurotarsi by Eurwentala Diversity of the Crurotarsi by Eurwentala
Some examples of the diversity of the crocodile-line archosaurs or Crurotarsi. This group was very common and diverse in the Triassic, and only a bit less so in the Jurassic and Cretaceous. Many of them were highly specialized and seem to have been active, possibly even warm-blooded animals. The group has many interesting examples of convergent evolution with dinosaurs and other groups. Now only the modern crocodiles remain.

In this picture, from top to bottom:
Saltwater Crocodile, Crocodylus porosus. The largest modern species of crocodile. An opportunistic predator that can eat anything from water buffalo to sharks.
Yacarerari. Belongs to the Cretaceous group Notosuchia. It was a cat-sized animal with very unusual mammal-like teeth.
Metriorhynchus. Member of the completely aquatic group Thalattosuchia. It had a tail fin and it's limbs were modified into flippers. It might have been viviparous, since it's body plan sure doesn't look suitable for laying eggs on dry land. Thalattosuchians are strongly convergent with ichthyosaurs and dolphins.
Terrestrisuchus. A small, obviously cursorian Sphenosuchian that could have weighed around 15 kg. It might be a juvenile specimen of Saltoposuchus.
Postosuchus. A member of Rauisuchia. It might have been partly or completely bipedal, since it's front limbs are small and weak. It was a large predator that had very similar head and teeth as the tyrannosaurid dinosaurs.
Effigia. Another dinosaur-like rauisuchian. It was a fast-running, bipedal animal very similar to ornithomimosaurs (the ostrich-mimic dinosaurs). It even had a toothless beak.
Desmatosuchus. A triassic aetosaur with very impressive armour. It was a herbivore with a surprisingly pig-like head.
Rutiodon. A crocodile-like phytosaur. Despite their appearance, phytosaurs were not closely related to the modern crocodiles. They seem to be another example of convergent evolution.
Add a Comment:
The-Episiarch Featured By Owner Dec 6, 2014
Nice! The Crurotarsi certainly get overlooked by most and end up in the shadow of the dinosaurs (even though they are very interesting in their own right). Ironically enough, some of those bipedal rauisuchians rather resemble the scaly theropods many people (who haven't come to terms with feathered dinosaurs) still think of when they think "dinosaurs". My fondness for these reptiles can be seen this piece here…
Which features a few of the genera you have illustrated above (though my piece is a rather off-beat take on those reptiles).
Heytomemeimhome Featured By Owner Apr 10, 2014
Ah if only anatosuchus and other notosuchians were here
Eurwentala Featured By Owner Apr 13, 2014
Yeah, I should make an updated version about this. :)
FancyKarp Featured By Owner Jan 20, 2014  Hobbyist Traditional Artist
Yacarerani, I feel so proud about one of the national languages of my country gave a name to a prehistoric creature! :D
Hellraptor Featured By Owner Sep 18, 2013  Hobbyist Digital Artist
Hard to belive that some of them are classed as crocodiles even though they didnt look like that. Very nice comparison pictue.
Aloodonguy67 Featured By Owner Jun 12, 2013  Student Artist
I love it!
NixKat Featured By Owner Mar 4, 2013  Hobbyist Traditional Artist
Eurwentala Featured By Owner Mar 8, 2013
Thanks. :)
Mechatherium Featured By Owner Feb 17, 2012  Student Digital Artist
As for Metriorhynchus being viviparous, if hard evidence of that was found it would be fascinating. That would make it the only archosaur I know of that ever was.
Eurwentala Featured By Owner Feb 24, 2012
Yes, it would be really fascinating, though unlikely. I'd think that if viviparity was easy to evolve in archosaurs, it would have happened at least a few times, if not more than a hundred, as it has in squamates.
Add a Comment: