Debeerius
Debeerius is a genus of chondrichthyan from the Mississippian age Bear Gulch Limestone of Montana, United States. It is named after Gavin [de Beer]. One species, D. ellefseni, is known, which is preserved in very fine detail. Melanin preserved in fossils of D. ellefseni indicates it possessed dark stripes down the length of its body. The jaw suspension of Debeerius was autodiastylic, and it is considered a member of the subclass Holocephali.