Hagfish, of the class Myxini and order Myxiniformes, are eel-shaped jawless fish. They are the only known living animals that have a skull but no vertebral column, although hagfish do have rudimentary vertebrae. Hagfish are marine predators and scavengers. Hagfish defend themselves against predators by releasing copious amounts of slime from glands in their skin.
Fish migration is mass relocation by fish from one area or body of water to another. Many types of fish migrate on a regular basis, on time scales ranging from daily to annually or longer, and over distances ranging from a few metres to thousands of kilometres. Such migrations are usually done for better feeding or to reproduce, but in other cases the reasons are unclear.
Balaenidae is a family of whales of the parvorder Mysticeti that contains mostly fossil taxa and two living genera: the right whale, and the closely related bowhead whale.
Gunnera is the sole genus of herbaceous flowering plants in the family Gunneraceae, which contains 63 species. Some species in this genus, namely those in the subgenus Panke, have extremely large leaves. Species in the genus are variously native to Latin America, Australia, New Zealand, Papuasia, Hawaii, insular Southeast Asia, Africa, and Madagascar. The stalks of some species are edible.
Cyclostomi, often referred to as Cyclostomata, is a group of vertebrates that comprises the living jawless fishes: the lampreys and hagfishes. Both groups have jawless mouths with horny epidermal structures that function as teeth called ceratodontes, and branchial arches that are internally positioned instead of external as in the related jawed fishes. The name Cyclostomi means "round mouths". It was named by Joan Crockford-Beattie.
Deltadromeus is a genus of theropod dinosaur from Northern Africa. It had long, unusually slender hind limbs for its size, suggesting that it was a swift runner. The skull is not known. One fossil specimen of a single species has been described, found in the Kem Kem Beds, which date to the mid-Cretaceous Period, about 95 million years ago. It may be a junior synonym of the contemporary Bahariasaurus. The classification of Deltadromeus has been in flux since its original description. In 2016, a South American theropod known as Gualicho shinyae was found to possess many similarities with Deltadromeus. Depending on the phylogenetic position of Gualicho, Deltadromeus may have been a neovenatorid carnosaur, a tyrannosauroid, or a basal coelurosaur if its close relation to Gualicho is legitimate. Other studies have considered it a ceratosaurian, more specifically a member of the family Noasauridae.
Dicraeosauridae is a family of diplodocoid sauropods who are the sister group to Diplodocidae. Dicraeosaurids are a part of the Flagellicaudata, along with Diplodocidae. Dicraeosauridae includes genera such as Amargasaurus, Suuwassea, Dicraeosaurus, and Brachytrachelopan. Specimens of this family have been found in North America, Asia, Africa, and South America. In 2023, a dicraeosaurid fossil was discovered in India for the first time. Their temporal range is from the Early or Middle Jurassic to the Early Cretaceous. Few dicraeosaurids survived into the Cretaceous, the youngest of which was Amargasaurus.
Mordacia mordax, known as the short-headed lamprey, Australian lamprey or Murray lamprey, is a species of Mordacia that lives in south-eastern Australia and Tasmania. Mordaciidae is made up of three species: M. praedox, M. mordax, and M. lapicida. M. mordax is a relatively rare, parasitic vertebrate and, along with the hagfishes, is part of the only surviving group of jawless organisms throughout vertebrate evolution. It has a thin eel-like body up to 50 cm (20 in) long, with two low dorsal fins on the back half. The skin is blue-gray or brown. Its eyes are small, and located on the top of its head.
The pouched lamprey, also known as the piharau in the North Island, korokoro,kanakana in the South Island, or wide-mouthed lamprey, is a species in the genus Geotria, which is the only genus in the family Geotriidae. The second species in the genus is the Argentinian lamprey, which was revalidated as a separate species in 2020. The pouched lamprey is native to the southern hemisphere. It spends the early part of its life in fresh water, migrating to the sea as an adult, and returning to fresh water to spawn and die.
The Pacific lamprey is an anadromous parasitic lamprey from the Pacific Coast of North America and Asia in an area called the Pacific Rim. It is a member of the Petromyzontidae family. The Pacific lamprey is also known as the three-tooth lamprey and tridentate lamprey.
Allodaposuchus is an extinct genus of crocodyliforms that lived in what is now southern Europe during the Campanian and Maastrichtian stages of the Late Cretaceous. Although generally classified as a non-crocodylian eusuchian crocodylomorph, it is sometimes placed as one of the earliest true crocodylians. Allodaposuchus is one of the most common Late Cretaceous crocodylomorphs from Europe, with fossils known from Romania, Spain, and France.
Mordacia is a genus of lamprey, the sole genus of the family Mordaciidae, also known as the southern topeyed lampreys.
Platypterygius is a historically paraphyletic genus of platypterygiine ichthyosaur from the Cretaceous period. It was historically used as a wastebasket taxon, and most species within Platypterygius likely are undiagnostic at the genus or species level, or represent distinct genera, even being argued as invalid. While fossils referred to Platypterygius have been found throughout different continents, the holotype specimen was found in Germany.
Lampreys are an ancient lineage of jawless fish of the order Petromyzontiformes. The adult lamprey is characterized by a toothed, funnel-like sucking mouth. The common name "lamprey" is probably derived from Latin lampetra, which may mean "stone licker", though the etymology is uncertain. Lamprey is sometimes seen for the plural form.
Caspiomyzon is a genus of lamprey in the family Petromyzontidae. They are native to Eastern Europe and parts of Western and Central Asia. Two of the three species in the genus are endemic to Greece.
Pholidosaurus is an extinct genus of neosuchian crocodylomorph. It is the type genus of the family Pholidosauridae. Fossils have been found in northwestern Germany. The genus is known to have existed during the Berriasian-Albian stages of the Early Cretaceous. Fossil material found from the Annero and Jydegård Formations in Skåne, Sweden and on the island of Bornholm, Denmark, have been referred to as a mesoeucrocodylian, and possibly represent the genus Pholidosaurus.
Mesomyzon mengae is an extinct lamprey from freshwater strata of the Early Cretaceous-aged Yixian Formation, in China.
Sooglossoidea is a superfamily of frogs. It contains only two highly divergent families consisting of three genera with two species each, one family being found in southwestern India and the other in the Seychelles.
This list of fossil fish research presented in 2023 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 2023.
Yanliaomyzon is an extinct genus of predatory lampreys that lived approximately 163 million years ago during the Middle Jurassic. It is found in the Yanliao Biota, including both the Daohugou Beds and the Tiaojishan Formation in Liaoning province, northern China. The genus has two species: Yanliaomyzon occisor and Yanliaomyzon ingensdentes. These species are significant for being the earliest lampreys to closely resemble modern species.
