Coelodus is an extinct genus of marine and possibly freshwaterpycnodont fish.[1] It contains only one definitive species,C. saturnusHeckel, 1854 (=C. rosthorniHeckel, 1854,C. suillusHeckel, 1854), from the LateCretaceous (Turonian toSantonian) ofSlovenia.[2] Other species from theLate Jurassic to theEocene have also been attributed to this genus based on isolated dental elements, but their assignment toCoelodus is uncertain, and this genus likely represents a non-monophyleticwastebasket taxon. A potential diagnostic trait is a prearticular tooth row with three regular highly elongated teeth.[2][3][4][5][6]
C. plethodonArambourg & Joleaud 1943 - Cenomanian/Turonian ofNiger, Maastrichtian ofAlgeria
C. portucalensisJonet 1981 - Cenomanian of Portugal
C. priemiLeriche 1903 - Late Jurassic of France
C. ribeiroiSauvage 1898 - Turonian of Portugal
C. rostratusGorjanović-Kramberger 1895 - Cenomanian of Slovenia
C. soleriRullán 1948 - Albian/Cenomanian ofCatalonia, Spain
C. stantoniWilliston 1900 - Albian of Kansas, USA (Kiowa Shale)
C. subsimilis(Cornuel 1880) Priem 1912 - Late Jurassic of France
C. syriacusHussakof 1916 - Late Cretaceous ofLebanon
C. vetteriGorjanović-Kramberger 1895 - Cenomanian-Turonian of Slovenia
C. zambiensisDartevelle & Casier 1949 - Turonian of the Democratic Republic of the Congo (Kongo Central)
A number of former species in this genus based on complete fossil specimens, such asC. costaeHeckel, 1856 (=C. achillis(Costa 1853),C. discusHeckel 1856,C. grandis(Costa 1855),C. pyrrhurusHeckel, 1854)C. subdiscusWenz, 1989,C. rosadoiSilva Santos, 1963 andC. toncoensisBenedetto & Sanchez ,1972 have since been reclassified into the generaOcloedus andCostapycnodus, and many of these dentition-only taxa may belong there instead.[2][5] Others, such as the formerC. muensteri, are now placed inAnomoeodus.
Indeterminate remains are known from theCsehbánya Formation ofHungary and theKem Kem Beds ofMorocco.[9][10] Notably, these formations, in addition to other formations thatCoelodus remains are known from worldwide, are freshwater deposits, suggesting at a potentiallyamphidromous lifestyle forCoelodus given its occurrence in marine environments as well.[10] It is possible that freshwater and brackish environments served asrefugia forCoelodus, allowing for it to survive theCretaceous-Paleogene extinction event.[11]
