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Cretoxyrhina (/ k r ɪ ˌ t ɒ k s i ˈ r h aɪ n ə /; meaning 'Cretaceous sharp-nose') is an extinct genus of large mackerel shark that lived about 107 to 73 million years ago during the late Albian to late Campanian of the Late Cretaceous.
Stethacanthus is an extinct genus of shark-like cartilaginous fish which lived from the Late Devonian to Late Carboniferous epoch, dying out around 298.9 million years ago. Fossils have been found in Australia , Asia , Europe and North America .
Stethacanthidae is an extinct family of prehistoric sharks. [1] It is estimated to have existed approximately between 380 and 300 million years ago. Members of this family are noted for their peculiar dorsal fin.
Shark bite marks have been seen on coelacanths; sharks are common in areas inhabited by coelacanths. [66] Electrophoresis testing of 14 coelacanth enzymes shows little genetic diversity between coelacanth populations. Among the fish that have been caught were about equal numbers of males and females. [8]
Acanthodii or acanthodians is an extinct class of gnathostomes (jawed fishes).They are currently considered to represent a paraphyletic grade of various fish lineages basal to extant Chondrichthyes, which includes living sharks, rays, and chimaeras.
Sharks could be facing extinction over the next couple of decades. Human interference is largely to blame for the species interference. Overfishing of sharks has increased as the global demand has ...
Xenacanthida (or Xenacanthiformes) is an order or superorder of extinct shark-like chondrichthyans (cartilaginous fish) known from the Carboniferous to Triassic. They were native to freshwater, marginal marine and shallow marine habitats. [1] Some xenacanths may have grown to lengths of 5 m (16 ft). [2]
Cosmopolitodus is an extinct genus of mackerel shark that lived between thirty and one million years ago during the late Oligocene to the Early Pleistocene epochs.Its type species is Cosmopolitodus hastalis, the broad-tooth mako (other common names include the extinct giant mako and broad-tooth white shark).