The Stark Shale is a black mudstone that formed in an anoxic, deep-water environment. Most fossils are pelagic animals that settled from higher in the water column. The most common fossils are conodonts, but fish and crustacean remains are occasionally found. Some fish.... Listracanthus is the most common fish fossil: Various spines can be found: As are dermal denticles: Fins are not unheard of: Some fish fragments are identifiable. Here are some skull elements of the shark Co