#fossil friday

Skin? Moisturized. Teeth? Tusk-like. Today’s mood? Mastodonsaurus giganteus. This animal lived during the Late Triassic about 215 million years ago. It’s an extinct relative of frogs and salamanders, but it probably behaved more like a crocodile: Its large, flat skull and tusk-like teeth (some of which protruded through the skull) seem to be adapted for seizing large prey. You can see this life-sized model in the Museum’s Hall of Vertebrate Origins! Plan your visit.

made in 2026, fossils made between 450-460 million years ago

Fossiliferous limestone for #FossilFridays

drew a T. rex

Today's random portfolio artwork is a life-size Diplodocus mural (human figure for scale), which I painted for the Children's Museum of Indianapolis.

A rooted dinosaur tooth of a Nanotyrannus sp. from the Hell Creek Formation in Carter County, Montana, United States. This unserrated basal morphology was previously known as the tooth taxon, Aublysodon amplus. While unserrated premaxillary teeth were supposedly an ontogenetically variable character, proposed to be found in young Gorgosaurus, recent studies on Nanotyrannus by Zanno and Napoli 2025 have shown this may not be the case implying these cannot belong to immature Tyrannosaurus rex. Which may mean they belong to Nanotyrannus lancensis and Nanotyrannus lethaeus. I'm not sure what this means for unserrated tyrannosaur premaxillary teeth from older deposits like the Judith River or Two Medicine Formation. Do they represent an undescribed Nanotyrannidae indet., or at least, a more basal eutyrannosaur/pantyrannosaur of some kind?

Check out the other regions' fossils here!