Cladocyclus Explained

Cladocyclus (derived from the Greek κλάδος/kládos ("branch") and κύκλος/kýklos ("circle")[1]) is an extinct genus of marine ichthyodectiform fish from the middle Cretaceous. It was a predatory fish of about 1.2m (03.9feet) in length.

Taxonomy

It contains the following species:

An indeterminate specimen, previously assigned to Chirocentrites, is known from the Albian-aged Pietraroja Plattenkalk of Italy.[4] Indeterminate specimens, represented by complete remains, are also known from the Cenomanian of Morocco,[5] which are not to be confused with C. pankowskii, which was discovered in the Kem Kem Beds in 2007, but has since been reclassified to the genus Aidachar.[6] [7]

The species C. lewesiensis Agassiz, 1887 from the Cenomanian of England and C. strehlensis Geinitz, 1868 from the Turonian of Germany, which were described based only on fossil scales, are considered nomen dubia and likely do not belong to this genus.[8] [9] The dubious species C. occidentalis Leidy, 1857 from the Coniacian-to-Campanian-aged Niobrara Formation of South Dakota, US is based on scales that likely belong to Ichthyodectes ctenodon.[10]

Ecology

Although C. gardneri and other cladocyclids are generally thought of as marine fish, the Australian species C. geddesi was recovered from a freshwater formation, despite showing clear adaptations to the open ocean. This specimen may have been of an individual that swam upstream from the ocean.

Notes and References

  1. http://www.summagallicana.it/Agassiz_nomenclator_zoologicus/Pisces.htm NOMENCLATOR ZOOLOGICUS – NOMENCLATORE ZOOLOGICO. Pisces
  2. de Castro Leal . Maria Eduarda . Brito . Paulo M . 2004-04-01 . The ichthyodectiform Cladocyclus gardneri (Actinopterygii: Teleostei) from the Crato and Santana Formations, Lower Cretaceous of Araripe Basin, North-Eastern Brazil . Annales de Paléontologie . 90 . 2 . 103–113 . 10.1016/j.annpal.2004.01.001 . 0753-3969.
  3. Berrell; Alvarado-Ortega; Yabumoto; Salisbury . Rodney W.; Jesús; Yoshitaka; Steven W. . 7 June 2014 . The First Record of the Ichthyodectiform Fish Cladocyclus from Eastern Gondwana: A New Species from the Lower Cretaceous of Queensland, Australia . Acta Palaeontologica Polonica . 59 . 4 . 903–902 . 10.4202/app.2012.0019 . 59019268 . free.
  4. Signore . M. . Pede . C. . Bucci . E. . C. . Barbera . 2006 . First report of the genus Cladocyclus in the Lower Cretaceous of Pietraroja (Southern Italy) . Bollettino della Societa Paleontologica Italiana . 45 . 1 . 141.
  5. Martill . David M. . Ibrahim . Nizar . Brito . Paulo M. . Baider . Lahssen . Zhouri . Samir . Loveridge . Robert . Naish . Darren . Hing . Richard . 2011-08-01 . A new Plattenkalk Konservat Lagerstätte in the Upper Cretaceous of Gara Sbaa, south-eastern Morocco . Cretaceous Research . 32 . 4 . 433–446 . 10.1016/j.cretres.2011.01.005 . 0195-6671.
  6. Forey . Peter L. . Cavin . Lionel . 2007 . A new species of Cladocyclus (Teleostei: Ichthyodectiformes) from the Cenomanian of Morocco . Palaeontologia Electronica.
  7. Mkhitaryan . T.G. . Averianov . A.O. . 2011-06-25 . New material and phylogenetic position of Aidachar paludalis Nesov, 1981 (Actinopterygii, Ichthyodectiformes) from the Late Cretaceous of Uzbekistan . Proceedings of the Zoological Institute RAS . 315 . 2 . 181–192 . 10.31610/trudyzin/2011.315.2.181 . 0206-0477 . free.
  8. Cockerell . T. D. A. . 1917 . European Fossil Fish-Scales . The American Naturalist . 51 . 601 . 61–63 . 10.1086/279587 . 0003-0147.
  9. Ekrt . Boris . Košt'ák . Martin . Mazuch . Martin . Voigt . Silke . Wiese . Frank . 2008 . New records of teleosts from the Late Turonian (Late Cretaceous) of the Bohemian Cretaceous Basin (Czech Republic) . Cretaceous Research . 29 . 4 . 659–673 . 10.1016/j.cretres.2008.01.013 . 0195-6671.
  10. Schumacher . Bruce . 1997 . Fossil Vertebrates of the Niobrara Formation in South Dakota, 1998 . Proceedings of the South Dakota Academy of Science . 76.