'' A fossil was discovered by Mr. Charlesworth in the
Woburn Sands Formation near
Potton, Bedfordshire, in a brown
sandstone layer with many
phosphate nodules. In
1874 this fossil was described by British palaeontologist
Harry Govier Seeley as a new taxon, named
Craterosaurus pottonensis. The
holotype and only definitive specimen of
Craterosaurus is stored in the
Sedgwick Museum of Earth Sciences under
accession number SMC B.28814. Seeley interpreted
Craterosaurus as being represented by a partial , which he found showed support for it as a member of
Dinosauria with uncertain relationships. It was possible that
Craterosaurus could be aligned with
Ceteosauria or
Iguanodon, but with limited material to compare Seeley did not classify
Craterosaurus further. In 1912 Hungarian palaeontologist
Franz Nopcsa re-evaluated
Craterosaurus with the hope that it could be classified more confidently, identifying that the material, which Seeley believed was a braincase, was instead part of the of a . From this, Nopcsa was able to positively compare
Craterosaurus to
Stegosaurus, as a member of
Stegosauria.
Craterosaurus was so similar to
Stegosaurus that Nopcsa considered their
synonymy possible, but retained them as separate due to the younger age and location of
Craterosaurus. British palaeontologist
Peter Galton revisited
Craterosaurus again in 1981, supporting its distinction as a
stegosaurid, and narrowing down its provenance to the upper
Aptian of the Woburn Sands at the youngest, though it is possibly
reworked from older
Neocomian or lower Aptian sediments. Galton also tentatively referred a second specimen,
NHMUK R.4134, to
Craterosaurus, having been found in the
Wealden Formation of
Sussex. Reviews of Stegosauria by British palaeontologist Susannah Maidment and colleagues since 2008 have instead found that
Craterosaurus is too incomplete to be diagnostic, and although it shows anatomy characteristic of Stegosauria, it lacks diagnostic features, so it is considered a
nomen dubium. == References ==