Marshosaurus bicentesimus
Late Jurassic (Tithonian)
Morrison Formation
Bone Cabin Quarry, Albany County wy USA
19mm tooth on 33mm matrix.

Dinosaur. Theropod.

Marshosaurus is a carnivorous dinosaur from the Late Jurassic of North America. It was smaller than Allosaurus and about the same size as Ceratosaurus. All three theropods are known from the Morrison Formation and lived at the same time but they are apparently not closely-related and may belong to three separate families.

Marshosaurus is probably the rarest of the three – certainly rarer than Allosaurus and you can never find an Allosaurus tooth when you want one.

Many collectors like to get at least one dinosaur tooth in matrix and this one is from the famous Bone Cabin Quarry, famous for an Apatosaurus skeleton that ended up at the American Museum of Natural History.