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 more unusual representatives, such as the goblin shark and megamouth shark.
Elasmobranchii is a subclass of Chondrichthyes or cartilaginous fish, including modern sharks, rays, skates, and sawfish. Members of this subclass are characterised by having five to seven pairs of gill clefts opening individually to the exterior, rigid dorsal fins and small placoid scales on the skin. The teeth are in several series; the upper jaw is not fused to the cranium, and the lower jaw is articulated with the upper. The details of this jaw anatomy vary between species, and help distinguish the different elasmobranch clades. The pelvic fins in males are modified to create claspers for the transfer of sperm. There is no swim bladder; instead, these fish maintain buoyancy with large livers rich in oil.
Cretoxyrhina 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. The type species, C. mantelli, is more commonly referred to as the Ginsu shark, first popularized in reference to the Ginsu knife, as its theoretical feeding mechanism is often compared with the "slicing and dicing" when one uses the knife. Cretoxyrhina is traditionally classified as the likely sole member of the family Cretoxyrhinidae but other taxonomic placements have been proposed, such as within the Alopiidae and Lamnidae.
Isurus is a genus of mackerel sharks in the family Lamnidae, commonly known as the mako sharks. They are largely pelagic, fast predatory fish capable of swimming at speeds up to 50 km/h (31 mph).
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.
The Toolebuc Formation is a geological formation that extends from Queensland across South Australia and the Northern Territory in Australia, whose strata date back to the Albian stage of the Early Cretaceous. Dinosaurs, pterosaurs, plesiosaurs, ichthyosaurs, protostegid turtles, sharks, chimaeroids and bony fish remains are among the fossils that have been recovered from the formation.
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.
Pseudocorax is an extinct genus of mackerel sharks that lived during the Late Cretaceous. It contains six valid species that have been found in Europe, the Middle East, North Africa, and North America. It was formerly assigned to the family Anacoracidae, but is now placed in its own family Pseudocoracidae along with Galeocorax. The former species "P." australis and "P." primulus have been reidentified as species of Echinorhinus and Squalicorax, respectively.
Synechodontiformes is an extinct order of prehistoric shark-like neoselachians, known from the Permian to the Paleogene. They are considered to be members of Neoselachii, the group that contains modern sharks and rays.
This list of fossil fishes described in 2019 is a list of new taxa of jawless vertebrates, placoderms, acanthodians, fossil cartilaginous fishes, bony fishes, and other fishes of every kind that were described during the year 2019, as well as other significant discoveries and events related to paleoichthyology that occurred in 2019.
Cretodus is an extinct genus of large mackerel sharks belonging to the proposed family Pseudoscapanorhynchidae. Cretodus lived during the Late Cretaceous, ranging from the Cenomanian to the Coniacian. The genus is well-known from strata deposited in the Western Interior Seaway, and from the Late Cretaceous of Europe, Africa, and possibly Asia. Cretodus is primarily represented in the fossil record by isolated teeth and vertebral centra, though a couple of associated dentitions and vertebral columns have been found.
Paraisurus is an extinct genus of mackerel sharks that lived during the Cretaceous. It contains four valid species, which have been found in Europe, Asia, North America, and Australia. A fifth species, P. amudarjensis, is now considered a synonym of P. compressus. While this genus is mostly known from isolated teeth, an associated dentition of P. compressus was found in the Weno Formation of Texas. It went extinct around the Albian-Cenomanian boundary, as a supposed Coniacian occurrence of "P. sp." is likely a misidentified pseudoscapanorhynchid.
Protolamna is an extinct genus of mackerel shark from the Cretaceous Period. The genus is known from Europe, Asia and North America.
Eoptolamna is an extinct genus of mackerel sharks that lived during the Cretaceous. It contains two valid species, E. eccentrolopha and E. supracretacea, which have been found in Europe and North Africa.
Archaeolamna is an extinct genus of mackerel sharks that lived during the Cretaceous. It contains three valid species which have been found in Europe, North America, and Australia. While it is mostly known from isolated teeth, an associated set of teeth, jaws, cranial fragments, and vertebrae of A. kopingensis is known from the Pierre Shale of Kansas. Teeth of A. k. judithensis were found with a plesiosaur skeleton with bite marks from the Judith River Formation of Montana. It was a medium-sized shark with an estimated total body length of 3–4 metres (9.8–13.1 ft).
Acutalamna is an extinct genus of mackerel shark from the Cretaceous period. It contains a singular species, A. karsteni. The type locality is the La Luna formation of Venezuela, but teeth have been found in France, Peru, Ecuador, and Lithuania. It is possible these teeth represent new species within this genus. Teeth included in this genus were originally attributed to "Priscusurus adruptodontus". The holotype and some of type series of this species were found to be indeterminate Squalicorax teeth, thus rendering it a nomen dubium. Other teeth in the type series of "P. adruptodontus" are indeterminate members of Acutalamna. It bears resemblance to both Anacoracids and Cretoxyrhinids, but has yet to be confidently ascribed to any family.
Lilamna is an extinct genus of mackerel sharks from the Wulagen Formation of the Tarim Basin, China. It was originally named Archaeolamna apophysata, but that generic name was preoccupied by Archaeolamna kopingensis. Lilamna was named as a replacement in accordance with the rules of the International Code of Zoological Nomenclature. Although formerly assigned to the family Lamnidae, it is now considered to be a potential member of the family Pseudoscapanorhynchidae. Since this family is otherwise restricted to the Cretaceous, it is possible that the holotype tooth was reworked into the late Eocene sediments it was found in.
This list of fossil fish research presented in 2021 is a list of new taxa of jawless vertebrates, placoderms, acanthodians, fossil cartilaginous fishes, bony fishes, and other fishes that were described during the year, as well as other significant discoveries and events related to paleoichthyology that occurred in 2021.
Ptychocorax is an extinct genus of mackerel sharks that lived during the Late Cretaceous. It contains three valid species that have been found in Europe and Asia. It was originally identified as a hybodontiform, but was later reidentified as an anacoracid. It has also been considered to belong to its own family, Ptychocoracidae. Ptychocorax is characterized by its unique dentition, combining Squalicorax-like, cutting anterior teeth with Ptychodus-like, crushing posterior teeth.
