Crocodylians are deceptive. I'm not just talking about their skill as aquatic ambush predators, concealed until the moment they're a blur of teeth and scales. Rather, the existing species of alligators, crocodiles, and gharials have often been incorrectly characterized as "living fossils" that have changed little since the Mesozoic. The fossil record readily dispels this notion, proving that crocodylians were even more varied in the past. With that in mind, Mourasuchus is a wonderful example of the greater crocodylian variety that once existed on our planet.

This weird caiman was first described in 1964 under the name Mourasuchus amazonensis. A handful of other species have been recognized since then, with the latest being Mourasuchus pattersoni named just this year by paleontologist Giovanne Cidade and colleagues from the Miocene strata of Venezuela. It's odd for a caiman. This was not a short-snouted little nipper, like the black caimans you've likely seen on natural history documentaries, but a long-faced crocodylian that looks like it's trying to do an impression of a baleen whale.

Such a strange skull is a sure sign Mourasuchus was doing something different than its modern relatives. But what? The long, wide snout with small teeth indicate that this caiman probably eschewed large, struggling prey for smaller fare. Following from this hypothesis, Cidade and coauthors suggest Mourasuchus a "gulp feeder" - a caiman that captured various small mollusks, crustaceans, and small fish en masse with its broad jaws. This wasn't filter feeding, the authors caution, as the caiman had no mechanism to separate sediment or plants from protein, but rather a uniquely crocodylian way of snaffling up little morsels in great quantities.

Mourasuchus
The skull of Mourasuchus pattersoni. Areas in white are fossil bone. Credit: Cidade et al. 2017

Fossil Facts

Name: Mourasuchus pattersoni

Meaning: The species name pattersoni honors paleontologist Bryan Patterson.

Age: Miocene, about 8 million years ago.

Where in the world?: Falcón state, Venezuela.

What sort of organism?: A caiman.

How much of the organism’s is known?: A nearly-complete skull with assorted postcrania including vertebrae, ribs, elements of the hips, and osteoderms.

Reference:

Cidade, G., Solórzano, A., Rincón, A., Riff, D., Hsiou, A. 2017. A new Mourasuchus (Alligatoroidea, Caimaninae) from the late Miocene of Venezuela, the phylogeny of Caimaninae and considerations on the feeding habits of Mourasuchus. PeerJ. doi: 10.7717/peerj.3056  

Previous Paleo Profiles:

The Light-Footed Lizard
The Maoming Cat
Knight’s Egyptian Bat
The La Luna Snake
The Rio do Rasto Tooth
Bob Weir's Otter
Egypt's Canine Beast
The Vastan Mine Tapir
Pangu's Wing
The Dawn Megamouth
The Genga Lizard
The Micro Lion
The Mystery Titanosaur
The Echo Hunter
The Lo Hueco Titan
The Three-Branched Cicada
The Monster of Minden
The Pig-Footed Bandicoot
Hayden's Rattlesnake Demon
The Evasive Ostrich Seer
The Paradoxical Mega Shark
The Tiny Beardogs
The Armored Fish King
North America's Pangolin
The Invisible-Tusked Elephant
The Mud Dragon
The Spike-Toothed Salmon
The Dream Coast Crocodile
Buriol's Robber
Ozimek's Flyer
The Northern Naustoceratopsian
The High Arctic Flyer
The Tomatillo From the End of the World
The Short-Faced Hyena
The Mighty Traveler from Egg Mountain
Keilhau's Ichthyosaur
Mexico's Ancient Horned Face
Mauricio Fernández's Plesiosaur
New Zealand's Giant Dawn Penguin
The Orange Sea Lion
Mongolia's Ginkgo Cousin
The Geni River Frog
Isabel Berry's Dinosaur