Cladoselachidae is an extinct

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

cartilaginous fish Chondrichthyes (; ) is a class of jawed fish that contains the cartilaginous fish or chondrichthyans, which all have skeletons primarily composed of cartilage. They can be contrasted with the Osteichthyes or ''bony fish'', which have skeleto ...

es closely related to, and possibly nested within,

Symmoriiformes Symmoriiformes is an extinct order of cartilaginous fish. Originally named Symmoriida by Zangerl (1981), the name has since been corrected to Symmoriiformes to avoid confusion with a family. The symmoriiform fossils record begins during the late ...

. They are characterized by having an elongated body with a spine in each of the two dorsal fins. In 2023, a paper describing a new cladoselachian, ''

Maghriboselache ''Maghriboselache'' is an extinct genus of cladoselachid symmoriiform fish that lived 369 million years ago during the Late Devonian (middle Famennian stage) of Morocco. The genus contains a Monotypic taxon, single species, ''M. mohmezanei''. ''M ...

'' found that it, and ''

Cladoselache ''Cladoselache'' ("branch shark") is an Extinction, extinct genus of shark-like chondrichthyan (cartilaginous fish) from the Late Devonian (Famennian) of North America. It was similar in body shape to modern Lamnidae, lamnid sharks (such as Isuru ...

'', were the only members of the family, greatly limiting the temporal range for this group to the

Late Devonian The Devonian ( ) is a geologic period and system of the Paleozoic era during the Phanerozoic eon, spanning 60.3 million years from the end of the preceding Silurian period at million years ago ( Ma), to the beginning of the succeeding ...

References

Cladoselachiformes
''Dictionary of Zoology'' (1999).
Evolution and paleontology (fish)
Animal Aqua. Symmoriiformes Late Devonian cartilaginous fish Prehistoric cartilaginous fish families {{paleo-cartilaginous-fish-stub