The tiger shark is a species of ground shark, and the only extant member of the genus Galeocerdo and family Galeocerdonidae. It is a large macropredator, with females capable of attaining a length of over 5 m. Populations are found in many tropical and temperate waters, especially around central Pacific islands. Its name derives from the dark stripes down its body, which resemble a tiger's pattern, but fade as the shark matures.
Galeocerdo is a genus of ground shark. Only a single species, G. cuvier, the tiger shark, is extant. The earliest fossils date back to the early Eocene epoch, (Ypresian), around 56–47.8 Million years ago. While historically considered a member of the requiem shark family Carcharhinidae, it is currently considered to be the only member of the family Galeocerdonidae. While this genus was historically considered diverse, including 21 extinct species, morphometric analysis conducted in 2021 suggested that the diversity of the genus included only 5 extinct species much lower than previously assumed. The oldest fossils of the extant G. cuvier date to the middle Miocene.
The Lamniformes are an order of sharks commonly known as mackerel sharks. It includes some of the most familiar species of sharks, such as the great white as well as less familiar ones, such as the goblin shark and megamouth shark.
Carcharodon is a genus of sharks within the family Lamnidae, colloquially called the "white sharks." The only extant member is the great white shark. The extant species was preceded by a number of fossil (extinct) species including C. hubbelli and C. hastalis. The first appearance of the genus may have been as early as the Early Miocene or Late Oligocene. Carcharocles megalodon is still argued by some paleontologists to be a close relative of Carcharodon carcharias - as well as being in the same genus. The megalodon's scientific name was originally "Carcharodon" megalodon, but more recently, the giant shark has been assigned by most scientists to either the genus Carcharocles or Otodus.
Orthacanthus is an extinct genus of fresh-water xenacanthiform cartilaginous fish, named by Louis Agassiz in 1843, ranging from the Upper Carboniferous into the Lower Permian. Orthacanthus had a nektobenthic life habitat, with a carnivorous diet. Multiple authors have also discovered evidence of cannibalism in the diet of Orthacanthus and of "filial cannibalism" where adult Orthacanthus preyed upon juvenile Orthacanthus. Synonyms of the genus Orthacanthus are Dittodus Owen, 1867, Didymodus Cope, 1883, Diplodus Agassiz, 1843, Chilodus Giebel, 1848.
Caturus is an extinct genus of predatory marine fishes in the family Caturidae in the order Amiiformes, related to modern bowfin. It has been suggested that the genus is non-monophyletic with respect to other caturid genera.
Xenacanthida is an order or superorder of extinct shark-like chondrichthyans known from the Carboniferous to Triassic. They were native to freshwater, marginal marine and shallow marine habitats. Some xenacanths may have grown to lengths of 5 m (16 ft). Most xenacanths died out at the end of the Permian in the End-Permian Mass Extinction, with only a few forms surviving into the Triassic.
Cheirolepis is an extinct genus of marine and freshwater ray-finned fish that lived in the Devonian period of Europe and North America. It is the only genus yet known within the family Cheirolepididae and the order Cheirolepidiformes. It was among the most basal of the Devonian actinopterygians and is considered the first to possess the "standard" dermal cranial bones seen in later actinopterygians.
Palaeoniscum is an extinct genus of ray-finned fish from the Permian period (Guadalupian-Lopingian) of England, Germany, Turkey, North America and Greenland, and possibly other regions. The genus was named Palaeoniscum in 1818 by Henri Marie Ducrotay de Blainville, but was later misspelled as Palaeoniscus by Blainville and other authors. Palaeoniscum belongs to the family Palaeoniscidae.
Physogaleus is an extinct genus of small requiem shark that lived from the Late Paleocene to Miocene epochs.
Otodus angustidens is an extinct species of prehistoric megatoothed sharks in the genus Otodus, which lived during the Late Eocene and Miocene epochs about 34 to 21 million years ago. The largest individuals were about 11–12 metres (36–39 ft) long. This shark is related to another extinct megatoothed shark, the famous Otodus megalodon.
Ptychodus is a genus of extinct large durophagous (shell-crushing) lamniform sharks from the Cretaceous period, spanning from the Albian to the Campanian. Fossils of Ptychodus teeth are found in many Late Cretaceous marine sediments worldwide.
Dercetis is a genus of prehistoric marine ray-finned fish. It is the type genus of the family Dercetidae, a group of slender, elongate aulopiform fish, which were related to modern lizardfish and grinners. It is known from the Late Cretaceous of Europe, the Middle East, and western North America.
Hybodontiformes, commonly called hybodonts, are an extinct group of shark-like cartilaginous fish (chondrichthyans) which existed from the late Devonian to the Late Cretaceous. Hybodonts share a close common ancestry with modern sharks and rays (Neoselachii) as part of the clade Euselachii. They are distinguished from other chondrichthyans by their distinctive fin spines and cephalic spines present on the heads of males. An ecologically diverse group, they were abundant in marine and freshwater environments during the late Paleozoic and early Mesozoic, but were rare in open marine environments by the end of the Jurassic, having been largely replaced by modern sharks, though they were still common in freshwater and marginal marine habitats. They survived until the end of the Cretaceous, before going extinct.
Anomoeodus is an extinct genus of prehistoric marine ray-finned fish belonging to the family Pycnodontidae. This genus primarily lived during the mid-to-late Cretaceous period, ranging from the Albian to the very end of the Maastrichtian age, and possibly into the Danian. The first fossils of Anomoeodus were described by Louis Agassiz in 1833, although they were described under Pycnodus. Some studies have recovered it as a wastebasket taxon.
Squaloraja is an extinct genus of ray-like marine chimaeriform fish from the Early Jurassic of Europe.
Cretalamna is a genus of extinct otodontid shark that lived from the latest Early Cretaceous to Eocene epoch. It is considered by many to be the ancestor of the largest sharks to have ever lived, such as Otodus angustidens, Otodus chubutensis, and Otodus megalodon.
Palaeospinax is an extinct genus of synechodontiform cartilaginous fish. Although several species have been described, the genus is considered nomen dubium because the type-specimen of the type species, Palaeospinax priscus, from the Late Triassic-Early Jurassic of Europe lacks appropriate diagnostic characters to define the genus.
Galeocerdo alabamensis is an extinct relative of the modern tiger shark. Nomenclature of this shark has been debated, and recent literature identified it more closely with the Physogaleus genus of prehistoric shark, rather than Galeocerdo. The classification of Physogaleus is known as tiger-like sharks while Galeocerdo refers to tiger sharks. In 2003, P. alabamensis was classified as Galeocerdo. However, in 2019, they were proclaimed to be more morphologically similar to the genus Physogaleus. This definition was based primarily on tooth shape, as the majority of information on P. alabamensis is a result of studying tooth fossils. Distinctions between Physogaleus and Galeocerdo are difficult with extinct sharks from the Oilgocene/Miocene as there is little paleobiological information allowing for hard conclusions.
Galeocerdo mayumbensis is an extinct species of sharks that lived in the Miocene period. A relative of the tiger shark, it lived in North America, South America, mainland Africa and Madagascar. The teeth of G. mayumbensis are different from those of G. aduncus.
