Ischyrhiza

<i>Ischyrhiza</i>

Ischyrhiza

Extinct genus of cartilaginous fishes


Ischyrhiza is an extinct genus of sclerorhynchoid ray from the Late Cretaceous and Early Paleogene.[3]

Quick Facts Scientific classification, Type species ...

It had a large, toothed rostrum closely resembling that of a modern-day sawfish. Despite formerly being classified within a family of extinct sawfish-like rays known as Sclerorhynchidae,[4] phylogenetic analyses indicate that Ischyrhiza, Schizorhiza, and Onchopristis form a distinct clade that groups closer with the extant family Rajidae, which contains the true skates, possibly rendering the suborder Sclerorhynchoidei paraphyletic.[5]

Fossils of the genus have been found in Canada, the United States, the Aguja Formation of Mexico, the Bissekty Formation of Uzbekistan, the Tamayama Formation of Japan, the Dukamaje Formation of Niger, the El Molino Formation of Bolivia, the Quiriquina Formation of Chile, and the Chota Formation of Peru.[6][7]


References

  1. ESTES, R. (1964) Fossil vertebrates from the Late Cretaceous Lance Formation, Eastern Wyoming. University of California Publications in Geological Sciences, 49: 1–180, 73 fig., 5 pl.
  2. Leidy (1856) - Notice of remains of extinct vertebrated animals of New-Jersey, collected by Prof. Cook of the State Geological Survey under the direction of Dr. W. Kitchell. Proceedings of the Academy of Natural Sciences of Philadelphia, 8: 220–221
  3. Fossils (Smithsonian Handbooks) by David Ward (Page 205)
  4. "Fossilworks: Sclerorhynchidae". fossilworks.org. Retrieved 17 December 2021.
  5. Villalobos‐Segura, Eduardo; Underwood, Charlie J.; Ward, David J. (2019). "The first skeletal record of the enigmatic Cretaceous sawfish genus Ptychotrygon (Chondrichthyes, Batoidea) from the Turonian of Morocco". Papers in Palaeontology. 7: 353–376. doi:10.1002/spp2.1287. ISSN 2056-2802. S2CID 210302939.
  6. The Paleobiology Database accessed on 8/21/09



Share this article:

This article uses material from the Wikipedia article Ischyrhiza, and is written by contributors. Text is available under a CC BY-SA 4.0 International License; additional terms may apply. Images, videos and audio are available under their respective licenses.