The Mesozoic is often called the Age of Reptiles. The term isn't so much about the most significant or prolific form of life on Earth - as Stephen Jay Gould once pointed out, our planet has always been in the Age of Bacteria - as much as it underscores what we think of as important when we look into the past.

As far as the span of Triassic, Jurassic, and Cretaceous goes, the stars have always been the non-avian dinosaurs and other weirdos like the plesiosaurs, pterosaurs, and mosasaurs, but we'd be sorely remiss if we neglected the other reptilian inhabitants of this past time. Not every saurian in the Age of Reptiles was bizarre or enormous, like a new species of lizard just described by paleontologists this week.

Just like the Age of Reptiles itself, Egg Mountain became famous for its connection with dinosaurs. This was a vast nesting ground for the hadrosaur Maiasaura. But this boneyard has also yielded much smaller, more delicate fossils, including a pair of small, nearly-complete lizard skeletons. These two fossils, paleontologist David DeMar and colleagues report, represent a new species dubbed Magnuviator ovimonsensis.

In the many-branched tree of lizard evolution, Magnuviator comes out as an iguanomorph. This is the broad  group that includes the anoles, basilisks, and iguanas that skitter around the American tropics today. But back in Cretaceous time, DeMar and coauthors write, the closest relatives of Magnuviator lived in Asia. The fossil stem from which today's iguanas and anoles sprung used to be spread in a different pattern over the planet, setting part of the foundation for what we see around us today.

But Magnuviator is also a reminder of something else. Dinosaurs and other large Mesozoic creatures dominate our attention. We're obsessed with the biggest and the weirdest. But we still know relatively little about the smaller inhabitants of that time. The lizards, snakes, mammals, and even tiny dinosaurs who lived during the Age of Reptiles are only just starting to come into focus. If you want to search the Mesozoic frontier, think small.

One skeleton of Magnuviator. Credit: David DeMar and Morgan Turner

Fossil Facts

Name: Magnuviator ovimonsensis

Meaning: Mighty traveler from Egg Mountain.

Age: Cretaceous, 75 million years ago.

Where in the world?: Montana, United States.

What sort of critter?: A lizard related to today's anoles and iguanas.

Size: About 14 inches long.

How much of the organism’s body is known?: Two nearly-complete skeletons.


DeMar, D., Conrad, J., Head, J., Varricchio, D., Wilson, G. 2017. A new Late Cretaceous iguanomorph from North America and the origin of New World Pleurodonta (Squamata, Iguania). Proceedings of the Royal Society B. doi: 10.1098/rspb.2016.1902

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