Myledaphus is an extinct genus of guitarfish. It currently contains four valid species found in North America (M. bipartitus, M. pustulosus), South America (M. araucanus), and Central Asia (M. tritus).[4] It is confirmed to have lived during the Late Cretaceous, with possible occurrences in the Paleocene and early Eocene.[3][5] While the genus is mostly known from teeth, two partial skeletons of M. bipartitus have been found in the Dinosaur Park Formation of Alberta.[6]
Myledaphus Temporal range:
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Tooth of Myledaphus bipartitus | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Chondrichthyes |
Subclass: | Elasmobranchii |
Superorder: | Batoidea |
Order: | Rhinopristiformes |
Family: | Rhinobatidae |
Genus: | †Myledaphus Cope, 1876[1] |
Type species | |
†Myledaphus bipartitus Cope, 1876
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Other species | |
Myledaphus remains have been found both in marine and fluvial (freshwater) deposits, suggesting it could tolerate a range of salinity.[7] In the Hell Creek Formation, composed predominantly of floodplain and riverine deposits, Myledaphus teeth are very common, accounting for a significant fraction of vertebrate remains found in microsites.[7]
Myledaphus has a durophagus dentition with blunt, polygonal-shaped (hexagonal to rhombic) teeth tessellated into a pavement suited for crushing and grinding hard-bodied prey. Many of their teeth show wear consistent with feeding on mollusks, which were common in the rivers of North America during the Late Cretaceous.[7]