Cladodus Explained

Cladodus is an extinct genus of cartilaginous fishes in the family Ctenacanthidae. As the name implies, they are a type of cladodont, primitive sharks with teeth designed to snag fish and swallow them whole, instead of sawing off chunks to swallow.

Fossils of Cladodus have been found in Barkip, Scotland,^[1] Bundock and Laurel Formations, Australia^[2] and in the Pitkin Formation (Carboniferous period) in Arkansas, United States. In addition, fossils attributable to Cladodus are known from the Manning Canyon Shale of Carboniferous age in the state of Utah.^[3]

Species

• †Cladodus alternatus St. John & Worthen, 1875
• †Cladodus angulatus Newberry & Worthen, 1866
• †Cladodus bellifer St. John & Worthen, 1875
• †Cladodus divaricatus Trautschold, 1874
• †Cladodus elegans Newberry & Worthen, 1870^[4] Remains (braincase and a tooth) have been found in Scotland (Clackmannan Group).^[5]
• †Cladodus eriensis Bryant, 1935
• †Cladodus formosus Hay, 1902
• †Cladodus gailensis Feichtinger et al., 2021^[6]
• †Cladodus marginatus Agassiz, 1843
• †Cladodus mirabilis Agassiz, 1843 (type species)
• †Cladodus pandatus St. John & Worthen, 1875
• †Cladodus springeri St. John & Worthen, 1875
• †Cladodus thomasi Turner, 1982 Known by teeth from the Lower Carboniferous Bundock Formation, North Queensland, and the Tournaisian Laurel Formation, Western Australia. Teeth reach 2.2-90 mm in length. This species was considered as a junior synonym of Stethacanthus obtusus by Lebedev (1996) but later reassigned to Cladodus due to a smaller number and distinct morphology of cusps.^[2]
• †Cladodus vanhornei St. John & Worthen, 1875
• †Cladodus yunnanensis Pan, 1964

See also

• List of prehistoric cartilaginous fish genera

Notes and References

1. Book: Catalogue of the western Scottish fossils. 19 February 2012. Public domain. 1876. Blackie. 76–.
2. Brett Roelofs, Milo Barham, Arthur J. Mory, Kate Trinajstics. January 2016. Late Devonian and Early Carboniferous chondrichthyans from the Fairfield Group, Canning Basin, Western Australia. Palaeontologia Electronica. 19. 1. 1-28. 10.26879/583.
3. Mickle . Kathryn E. . 9 September 2011 . The early actinopterygian fauna of the Manning Canyon Shale Formation (upper Mississippian, lower Pennsylvanian) of Utah, U.S.A. . Journal of Vertebrate Paleontology . 31 . 5 . 962–980 . 10.1080/02724634.2011.595622 . 2011JVPal..31..962M . 129224357 . 9 September 2020.
4. Comments on the selachian genus Cladodus Agassiz, 1843. Christopher J. Duffin and Michal Ginter,Journal of Vertebrate Paleontology, 2006, Volume 26, Issue 2, pages 253-266,
5. The Braincase and Jaws of Cladodus from the Lower Carboniferous of Scotland. Michal Ginter and John G. Maisey, Palaeontology, March 2007, Volume 50, Issue 2, pages 305–322,
6. Feichtinger . I. . Ivanov . A. O. . Winkler . V. . Dojen . C. . Kindlimann . R. . Kriwet . J. . Pfaff . C. . Schraut . G. . Stumpf . S. . 2021 . Scarce ctenacanthiform sharks from the Mississippian of Austria with an analysis of Carboniferous elasmobranch diversity in response to climatic and environmental changes . Journal of Vertebrate Paleontology . 41 . 2 . e1925902 . 10.1080/02724634.2021.1925902 . 2021JVPal..41E5902F . 237518044 .