1.45" Theropod Dinosaur (Marshosaurus?) Tooth - Colorado

This is a 1.45" theropod dinosaur tooth from the Morrison Formation of Colorado. I believe this tooth is a Megalosaurid (Marshosaurus) but unfortunately the area that would have contained some important distinguishing characteristics was damaged and restored.

Unlike Allosaurus teeth, the serrations on Marshosaurus teeth only continue half-way down the blade on one edge. The serrations on that edge also don't "spiral" on Marshosaurus teeth. The area where the serrations would have ended or the spiral would have been was damaged.

Why do I believe it's Marshosaurus?

1. The serrations do not appear to go all the way down the tooth on that edge.

2. The thinner, hook shape of the tooth is more often seen in Marshosaurus.

3. The precise section of the quarry where this tooth was found was producing a lot of Marshosaurus teeth.

The tooth is was left partially embedded in the colorful rock it was found in during preparation. This remaining rock also creates a natural display base for the tooth. There is a fairly large gap fill running up the lower half of the tooth and then over to one edge.

There are three described Megalosaurs in the Morrison Formation; Marshosaurus, Stokesosaurus and Torvosaurus. The shape and coarseness of serrations don't match Torvosaurus.
Based on the other material/teeth found at the quarry odds favor it being from Marshosaurus.

Marshosaurus is a genus of medium-sized Megalosaur from the Late Jurassic, Morrison Formation. In 2010, Gregory S. Paul estimated its length at 4.5 meters (15 feet) and its weight at 200 kilograms (440 pounds). It is one of the rarer theropods in the Morrison Formation: only a single partial specimen has ever been recovered.

An artist's reconstruction of Marshosaurus,  by Danny Cicchett. Creative Commons License
An artist's reconstruction of Marshosaurus, by Danny Cicchett. Creative Commons License
Dinosaurs Of America Quarry, Dinosaur, Colorado
Brushy Basin Member, Morrison Formation
1.45" long
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