Listracanthidae is a proposed family of extinct

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

. It currently includes the genera ''

Listracanthus ''Listracanthus'' is a genus of extinct chondrichthyan with uncertain affinities. Species of ''Listracanthus'' are known primarily from their tremendous, feather-like denticles, which range up to four inches in length. The denticles had a large ...

'' and ''

Acanthorhachis ''Acanthorhachis'' is an enigmatic extinct genus of chondrichthyan from the Carboniferous period. Its name is derived from the Greek word ''acanthos'' meaning "spine" and the Greek suffix for spine, -''rhachis''. This is due to the spine-like der ...

''. This clade is likely included within Elasmobranchii, but its placement within it is uncertain. Both genera are known from their distinctive spiny dermal dentictles which coat the exterior of their long, slender bodies. They are known from the

Viséan The Visean, Viséan or Visian is an age in the ICS geologic timescale or a stage in the stratigraphic column. It is the second stage of the Mississippian, the lower subsystem of the Carboniferous. The Visean lasted from to Ma. It follows the ...

to the

Early Triassic The Early Triassic is the first of three epochs of the Triassic Period of the geologic timescale. It spans the time between Ma and Ma (million years ago). Rocks from this epoch are collectively known as the Lower Triassic Series, which is a un ...

, mainly from what is now the

northern hemisphere The Northern Hemisphere is the half of Earth that is north of the Equator. For other planets in the Solar System, north is defined as being in the same celestial hemisphere relative to the invariable plane of the solar system as Earth's Nort ...

. However, there is a possible occurrence in

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

References

Prehistoric cartilaginous fish families Cartilaginous fish Mississippian first appearances Early Triassic extinctions {{Paleo-cartilaginous-fish-stub