Helicoprion

Uncommon card · No. 100330

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 meaning "spiral saw". Although numerous species were subsequently assigned to the genus, only H. bessonowi, H. davisii, and H. ergassaminon are recognized following a 2013 revision. The three species are distinguished by the shape and spacing of their tooth crowns. Helicoprion is mainly known from its fused, spiral-shaped tooth whorls, which account for almost all documented fossils of the taxon. The position...

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