Episode 565: A tyrannosaur tooth embedded in a hadrosaur skull. plus hadrosaurs breaking their tails while mating, a diplodocoid with a broken tail tip, and many more paleopathologies.

News:

• There’s a new herrerasaur, Ptychotherates bucculentus source
• Hadrosaurs may have injured their tails while mating source
• A Barosaurus with a long whip-like tail had a fracture at the tip of its tail source
• A tyrannosaur lost the tip of its tooth in the skull of an Edmontosaurus source
• A Plateosaurus with a bone infection in its right arm is the oldest known dinosaur bone infection source
• Cancer has been around for millions of years, including in dinosaurs source
• A few titanosaurs were found with cysts in their tails source
• A mamenchisaurid sauropod had a tumor on its shoulder and arm source

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The dinosaur of the day: Koparion

• Small troodontid that lived in the Late Jurassic in what is now Utah, U.S. (Morrison Formation)
• Holotype is a single tooth, catalogued as DINO 3353
• Only the crown (the root is missing)
• A hypothetical illustration depicts it as a cute dinosaur, covered in feathers, walking on two legs, with a long tail, short snout, and big eyes
• Know it’s a troodontid tooth (really curved, has blood pits, etc)
• Specifically a maxillary tooth (from the upper jaw)
• Tooth is about 2 mm tall
• Tooth is serrated
• Troodontids are bird-like theropod dinosaurs that lived in the Late Jurassic to Late Cretaceous
• At the time it was found, it was the oldest known troodontid
• Oldest one now known is Hesperornithoides, named in 2019 (talked about in ep 245, also from the Morrison Formation)
• Type and only species is Koparion douglassi
• Named in 1994 by Daniel Chure
• Found near Dinosaur National Monument
• Morrison Formation generally known for the larger dinosaurs, like the sauropods, and Allosaurus
• Genus name means a small surgical knife, and alludes to the small size of the serrated tooth
• Species name in honor of Earl Douglass, who found and excavated the dinosaur quarry that led to Dinosaur National Monument being created
• Found while screen washing (soak the dirt or clay or sand in water, wash in fine-mesh screens, to leave behind the fossils)
• Helps show there were more small theropods in the area than previously thought
• Chure wrote: “Although I am reluctant to inflict another tooth taxon upon fellow dinosaur workers, DINO 3353 is distinctive and can be separated from other Morrison theropods and other troodontids, and formal systematic recognition is appropriate.”
• Chure also wrote: “Scott Madsen, George Engelmann, and a host of volunteers have run the screenwashing program at Dinosam; without which the specimen described here would never have been found. Scott Madsen cleaned and prepared the specimen for scanning electron microscopy. Phil Currie provided stimulating discussion about troodont teeth.”

Fun Fact:

Some prehistoric communities had bone infection epidemics (dinosaurs and other prehistoric animals).

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