Stegoceras validum - Skull Dome

In stock

An ultra rare Top Quality Stegoceras validum dome (frontoparietal skull bone) from the late Cretaceous of northern North America. An April Fossil of the Month. Stegoceras is a smaller sized pachycephalosaurid dinosaur, and like Pachycephalosaurus, it is a dinosaur which is famous for its large domed head surrounded by spikes. This is excellent quality juvenile dome with good color / patina. No cracks or restoration. There is a small sheer on the left side that occured prior to fossilization since it has the natural patina. Otherwise a complete dome. An ultra rare Stegoceras dome!  Legally collected on private land in the Judith River Fm., Hill Co., Montana. An excellent collector's quality Stegoceras dome. Comes with a Riker display case. Authenticity guaranteed. You don't see Stegoceras domes very often. A special piece! (Photo series = top, bottom, right side, left side, and rear).

DP50       SIZE: 2-5/8" x 2"   (1-1/2" thick)  

Note - Adding 13 new Pachy spikes, claws and teeth in April 2023.   Link to Pachy fossils catalog

Stegoceras is a smaller sized pachycephalosaurid dinosaur, and a probable ancestor to Pachycephalosaurus. Stegoceras lived in the late Campanian in No. America. This specimen is from the Judith River formation.

Pachycephalosaurus is the dinosaur with the large domed skull which is surrounded by bony nodes or spikes, and it names means “thick-headed lizard” that lived during the late Cretaceous period in North America. The domed skull is quite thick (up to 10 inches) and believed that it may have been used in intra-species combat. Many fossilized skulls have been found with healed wounds. Pachycephalosaurus was a bipedal dinosaur that grows to 15 feet and 2000 lbs, and the largest of the Pachycephalosaur dinosaurs. Other named Pachycephalosaurs found in the Hell Creek Fm. include Dracorex and Stygimoloch. Dracorex and Stygimoloch, which exhibit much smaller domes and much larger spike ornamentation, are now believed to be early growth stages of Pachycephalosaurus. Only one species exists which is Pachycephalosaurus wyomingensis. 

Pachycephalosaurus fossils are quite rare. In fact, only one partial skeleton has been found. A dinosaur census conducted by the Hell Creek Project calculated relative abundance of the Pachycephalosaurus was 1% of the population. Today, we find fossilized teeth, unguals (claws), spikes, and non-associated bones.

Pachycephalosaurus tooth identification. Thescelosaurus teeth are routinely identified and sold as Pachycephalosaurus teeth since they maxillary teeth have a similar shape and size. There has been some good work done presented in the Fossil Forum. The Fossil Forum author concludes that Pachycephalosaurus maxillary teeth can be differentiated from Thescelosaurus teeth since the Pachy teeth exhibit  “vertical ridges are more pounced, fewer and a more prominent center ridge may exist. There is also no symmetry with the crowns.” Several good photographic references are provided. Link to the Fossil Forum discussion. A dominant center ridge appears to be consistent and lack of symmetry on the crown appeared in most of the Pachycepholsaur reference teeth.  That said, rooted teeth from both species are very scarce and are highly collectable.