Caseodus
Extinct genus of cartilaginous fish
From Wikipedia, the free encyclopedia
Caseodus is an extinct genus of eugeneodont from the Carboniferous of what is now the Midwestern United States,[2] and potentially the Early Triassic of what is now British Columbia, Canada.[3] The genus contains two Carboniferous species, C. basalis and C. eatoni, which are differentiated by the anatomy of their teeth but are otherwise identical.[2][4] A third species, C. varidentis, is known from the Early Triassic Sulphur Mountain Formation,[3] but due to its wildly different skull and tooth morphology it is questionable if it belongs in the genus.[5] The genus name is in honor of paleoichthyologist Gerard Case,[2] and the type species was originally placed in the genus Orodus.[4][6]
| Caseodus Temporal range: Carboniferous - Early Triassic? | |
|---|---|
 | |
| Holotype of Caseodus basalis | |
 | |
| Life reconstruction of Caseodus | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Chondrichthyes |
| Order: | †Eugeneodontiformes |
| Family: | †Caseodontidae |
| Genus: | †Caseodus Zangerl, 1981 |
| Type species | |
| Orodus basalis (Cope, 1894) | |
| Species[1] | |
| |
All species in the genus grew to approximately 1–1.5 m (3.3–4.9 ft) in length.[2][3][4] The Carboniferous species had upper jaws which supported teeth and a row of fused teeth (termed a tooth-whorl) along the midline of the lower jaw.[2][5] The Triassic species entirely lacked upper jaws and had an elongated projection, termed a rostrum, which extended from the lower jaw and supported the lower tooth-whorl.[5] Caseodus varidentis (if included in the genus) is one of the few eugeneodontid genera that survived the end-Permian mass extinction event, and is one of the last surviving genera of this clade.[3]
