Coelodus
Coelodus is an extinct genus of marine and possibly freshwater pycnodont fish. It contains only one definitive species, C. saturnus Heckel, 1854, from the Late Cretaceous of Slovenia. Other species from the Late Jurassic to the Eocene have also been attributed to this genus based on isolated dental elements, but their assignment to Coelodus is uncertain, and this genus likely represents a non-monophyletic wastebasket taxon. A potential diagnostic trait is a prearticular tooth row with three regular highly elongated teeth.
Taxonomy
In addition to C. saturnus, the following are all dubiously classified into this genus:C. anomalus Choffat & Priem 1904 - Barremian of PortugalC. arcuatus Woodward 1918 - Berriasian of England C. bocagei Sauvage, 1897 - Cenomanian and Turonian of PortugalC. brownii Cope 1895 - Albian of Kansas, USA C. bursauxi Priem 1912 - Maastrichtian of TunisiaC. cantabrigiensis Woodward 1895 - Cenomanian of England C. choffati Sauvage 1898 - Cenomanian of PortugalC. crassus Dartevelle & Casier, 1949 - Maastrichtian of the Democratic Republic of the Congo C. cuneiformis Sauvage 1898 - Cenomanian of PortugalC. decaturensis Gidley 1913 - Albian of Texas, USAC. delabathiei - Coniacian/Santonian of MadagascarC. delgadoi Sauvage 1898 - Cenomanian of PortugalC. ellipticus Egerton 1877 - Albian of England C. fabadens Gidley 1913 - Early Cretaceous of Texas, USAC. fabarius - Early Cretaceous of ItalyC. feddeni - Paleocene of Sindh, PakistanC. gasperinii Gorjanović-Kramberger 1902C. glauconiensis Leriche, 1929 - Santonian of BelgiumC. gridellii d'Erasmo 1952 - Late Cretaceous of ItalyC. gyrodoides Egerton 1877 - Late Cretaceous of Lyme Regis, EnglandC. hirudo - Valanginian of EnglandC. inaequidens Woodward 1893 - Cenomanian of England C. jacobi Menon & Prasad 1959 - Eocene of Assam, India C. jourdani de Saint Seine 1949 - Kimmeridgian of France C. laevidens Woodward 1918 - Berriasian of England C. latus Gorjanović-Kramberger 1895 - Cenomanian of SloveniaC. laurentii Priem 1908 - Late Jurassic of FranceC. malwaensis Chiplonkar & Ghare 1977 - Cenomanian of India C. mesorachis Heckel 1854 - Cenomanian/Turonian of CroatiaC. mokattamensis Priem 1897 - Eocene of Egypt and QatarC. morgani Priem 1908 - Maastrichtian of IranC. multidens Woodward 1918 - Barremian of England C. multipinnatus Gorjanović-Kramberger 1895 - Cenomanian-Turonian of SloveniaC. muraltii Heckel 1848 - Late Cretaceous of CroatiaC. oblongus Heckel 1854 - Cenomanian/Turonian of CroatiaC. ovalis Gorjanović-Kramberger 1895C. parallelus - Turonian of EnglandC. pellei - Early Eocene of TunisiaC. plethodon Arambourg & Joleaud 1943 - Cenomanian/Turonian of Niger, Maastrichtian of AlgeriaC. portucalensis Jonet 1981 - Cenomanian of PortugalC. priemi Leriche 1903 - Late Jurassic of FranceC. ribeiroi Sauvage 1898 - Turonian of PortugalC. rostratus Gorjanović-Kramberger 1895 - Cenomanian of SloveniaC. soleri Rullán 1948 - Albian/Cenomanian of Catalonia, SpainC. stantoni Williston 1900 - Albian of Kansas, USA C. subsimilis Priem 1912 - Late Jurassic of FranceC. syriacus Hussakof 1916 - Late Cretaceous of LebanonC. vetteri Gorjanović-Kramberger 1895 - Cenomanian-Turonian of SloveniaC. zambiensis Dartevelle & Casier 1949 - Turonian of the Democratic Republic of the CongoA number of former species in this genus based on complete fossil specimens, such as C. costae Heckel, 1856, C. discus Heckel 1856, C. grandis ''C. subdiscus Wenz, 1989, C. rosadoi Silva Santos, 1963 and C. toncoensis Benedetto & Sanchez,1972 have since been reclassified into the genera Ocloedus and Costapycnodus, and many of these dentition-only taxa may belong there instead. Others, such as the former C. muensteri, are now placed in Anomoeodus.
Indeterminate remains are known from the Csehbánya Formation of Hungary and the Kem Kem Beds of Morocco. Notably, these formations, in addition to other formations that Coelodus remains are known from worldwide, are freshwater deposits, suggesting at a potentially amphidromous lifestyle for Coelodus given its occurrence in marine environments as well. It is possible that freshwater and brackish environments served as refugia for Coelodus'', allowing for it to survive the Cretaceous-Paleogene extinction event.