Xenacanthidae
Encyclopedia
Xenacanthidae is a family of prehistoric shark
s in the order
Xenacanthida
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Shark
Sharks are a type of fish with a full cartilaginous skeleton and a highly streamlined body. The earliest known sharks date from more than 420 million years ago....
s in the order
Order (biology)
In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...
Xenacanthida
Xenacanthida
Xenacanthida is an order of prehistoric sharks that appeared during the Lower Carboniferous period. The family includes the families Xenacanthidae, Diplodoselachidae, and Orthacanthidae. The most notable members of the group are the genera Xenacanthus and Orthacanthus. Some Xenacanthus may have...
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