Squalicorax, commonly known as the crow shark, is a genus of extinct lamniform shark known to have lived during the Cretaceous period. The genus had a global distribution in the Late Cretaceous epoch. Multiple species within this genus are considered to be wastebasket taxon due to morphological similarities in the teeth.
Ichthyodectiformes is an extinct order of marine stem-teleost ray-finned fish. The order is named after the genus Ichthyodectes, established by Edward Drinker Cope in 1870. Ichthyodectiforms are usually considered to be some of the closest relatives of the teleost crown group.
Belonostomus is a genus of prehistoric ray-finned fish that was described by Louis Agassiz in 1844. It is a member of the order Aspidorhynchiformes, a group of fish known for their distinctive elongated rostrums.
Apateodus is a genus of prehistoric marine ray-finned fish which was described by Woodward in 1901. It was a relative of modern lizardfish and lancetfish in the order Aulopiformes, and one of a number of prominent nektonic aulopiforms of Cretaceous marine ecosystems.
Pachyrhizodus is an extinct genus of ray-finned fish that lived during the Cretaceous to Paleocene in what is now Europe, North America, South America, and Oceania. Many species are known, primarily from the Cretaceous of England and the midwestern United States.
Amblypterus is an extinct genus of freshwater ray-finned fish that lived during the Gzhelian and Cisuralian epoch in what is now Europe and possibly India and Argentina.
Pycnodontiformes is an extinct order of primarily marine bony fish. The group first appeared during the Late Triassic and disappeared during the Eocene. The group has been found in rock formations in Africa, Asia, Europe, North and South America. They were small to middle-sized fish, generally with laterally-compressed deep bodies, some with almost circular outlines, adapted for manuverability in reef-like environments, though the group was morphologically diverse. Most, but not all members of the groups had jaws with round and flattened teeth, well adapted to crush food items (durophagy), such as echinoderms, crustaceans and molluscs. Some pyncodontiformes developed piranha like teeth used for eating flesh. Most species inhabited shallow marine reef environments, while a handful of species lived in freshwater or brackish conditions. While rare during the Triassic and Early-Middle Jurassic, Pycnodontiformes became abundant and diverse during the Late Jurassic, exhibiting a high but relatively static diversity during the Early Cretaceous. At the beginning of the Late Cretaceous they reached their apex of morphological and species diversity, after which they began to gradually decline, with a more sudden decline at the end of the Cretaceous due to the collapse of reef ecosystems, finally becoming extinct during the Eocene. They are considered to belong to the Neopterygii, but their relationship to other members of that group is uncertain.
Coccodus is an extinct genus of extinct pycnodontid fish that lived during the lower Cenomanian. The various species had a pair of massive, curved spines emanating from the lower sides of the head, and one curved spine on the top of its head. Unlike most pycnodontids, Coccodus species had a comparatively long body, giving the living animals a superficial resemblance to a scaly chimaera.
Asarotus is an extinct genus of prehistoric marine ray-finned fish from the Niobrara Formation of Nebraska, during the Campanian. The type species, A. arcanus is only known from poorly preserved single specimen, which makes hard to classify existing orders of Cretaceous actinopterygians. It is thus classified as the only member of its family Asarotidae and order Asarotiformes.
Telepholis is an extinct genus of prehistoric bony fish that lived from the Cenomanian to Campanian.
Acentrophorus is an extinct genus of prehistoric freshwater and marine ray-finned fish from the Roadian to the Wuchiapingian of England, Germany (Kupferschiefer), Italy and Russia. There may also be a Triassic occurrence in Australia.
Anomoeodus is an extinct genus of prehistoric marine ray-finned fish belonging to the family Pycnodontidae. This genus lived during the Late Cretaceous period, ranging from the Albian to Maastrichtian ages, and had a wide geographic distribution, with fossils found in France, Belgium, the Netherlands, Spain, Egypt, Uzbekistan, and the United States. Some studies have recovered it as a wastebasket taxon. The first fossils of Anomoeodus were described by Louis Agassiz in 1833, although they were described under Pycnodus.
Athrodon is an extinct genus of marine pycnodontid fish that lived in shallow seas in what is now England, Germany, Spain and France from the Late Jurassic until the genus' extinction during the start of the late Cretaceous. The various species are very similar in splenial bone and tooth morphology to Mesodon. Otherwise, no articulated or complete specimen is known: all fossil specimens are bone fragments and disarticulated teeth. This genus is thought to be diagnosed by the presence of four lateral tooth rows. The presence of this genusin the Cretaceous is disputed, as the remains of Cretaceous species could belong to other genera.
Coccolepis is an extinct genus of prehistoric ray-finned fish in the family Coccolepididae. Originally including most species within the family, it is now restricted to two species from the Late Jurassic Solnhofen Limestone of Germany. The holotype of C. bucklandi, designated and described by Louis Agassiz, was thought to be lost but was later rediscovered in Neuchâtel.
Gyronchus is an extinct genus of prehistoric ray-finned fish from the Jurassic. This genus is wastebasket taxon used for pycnodonts like Macromesodon and Turbomesodon.
Ophiopsis is an extinct genus of prehistoric ray-finned fish belonging to the family Ophiopsidae. Specimens are known from the Tithonian-age Solnhofen Formation of Bavaria, Germany.
Plethodus is an extinct genus of prehistoric ray-finned fish. It is the type genus of the family Plethodidae.
Macropycnodon is an extinct genus of ray-finned fish which existed in New Mexico during the upper Cretaceous period.
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.
Ophiopsiella is an extinct genus of prehistoric ray-finned fish.
