Guadalupian life

Helicoprion is an extinct genus of large shark-like cartilaginous fish that lived from the Early to the Middle Permian, about 290-270 million years ago. Helicoprion is a member of the Eugeneodontiformes, an extinct order of cartilaginous fish within the clade Holocephali, a group today represented only by chimaeras. It is also the type genus of the Helicoprionidae, a family of eugeneodonts characterised by distinctive tooth structures called tooth whorls. Helicoprion was first named in 1899 by Alexander Karpinsky on the basis of fossils discovered in Russia and Australia, the generic name mean

mass extinction that occurred 273 million years ago in the early Guadalupian of the Permian period

Mamulichthys is an extinct genus of bony fish in the order Discordichthyiformes only known from the middle Permian of Russia. Like other members of its order, the fish differs from the majority of other bony fish due to the presence of fin spines on its pectoral and dorsal fins. The fish is one of the most complete members of the order, with the holotype specimen preserving a majority of the body, up to around the second dorsal fin. More recently, Mamulichthys has been though to potentially be a synonym of another member of the order ,Mutovinia, due to the similarities in their odontode shape.