The Mesobatrachia is a paraphyletic group of relatively primitive frogs. At the end of 2016, it contained 3 superfamilies, 6 families, 16 genera, and 244 species. Recognized as a group in 1993, the name is contrasted with the primitive Archaeobatrachia and the more diverse and advanced Neobatrachia.
The Pipidae are a family of primitive, tongueless frogs. There are 41 species in the family, found in tropical South America and sub-Saharan Africa.
The Mexican burrowing toad is the single living representative of the family Rhinophrynidae. It is a unique species in its taxonomy and morphology, with special adaptations to assist them in digging burrows where they spend most of their time. These adaptations include a small pointed snout and face, keratinized structures and a lack of webbing on front limbs, and specialized tongue morphology to assist in feeding on ants and termites underground. The body is nearly equal in width and length. It is a dark brown to black color with a red-orange stripe on its back along with splotches of color on its body. The generic name Rhinophrynus means 'nose-toad', from rhino- (ῥῑνο-), the combining form of the Ancient Greek rhis and phrunē.
The Rhinophrynidae are a family of frogs containing one extant genus, the monotypic Rhinophrynus, and a number of fossil genera. The family is sometimes known as the Mexican burrowing toads or simply burrowing toads.
Kaloula is a genus of microhylid frogs found in southern and eastern Asia. They are sometimes known as the Asian narrowmouth toads.
Palaeobatrachus is an extinct genus of frogs from Europe that existed from the middle Eocene to the middle Pleistocene, spanning almost 50 million years. They were obligately aquatic, and would have not spent much time on dry land. They are one of two genera and by far the largest genus in the family Palaeobatrachidae, which are considered to be members of Pipimorpha, related to the South American-African family Pipidae, which includes the African clawed frog and Surinam toad.
Hyloidea is a superfamily of frogs. Hyloidea accounts for 54% of all living anuran species. The superfamily Hyloidea branched off from its closest relative, the Australobatrachia, during the mid-Cretaceous. The fossil evidence found during the Cretaceous-Paleogene extinction event could not determine the effects upon the frogs, due to the lack of fossils. Increased forestation erupted after this extinction, possibly leading to more arboreal adaptations of these anurans to be best suited for this habitat.
The Albanerpetontidae are an extinct family of small amphibians, native to the Northern Hemisphere during the Mesozoic and Cenozoic. The only members of the order Allocaudata, they are thought to be allied with living amphibians belonging to Lissamphibia. Despite a superficially salamander-like bodyform, their anatomy is strongly divergent from modern amphibians in numerous aspects. The fossil record of albanerpetontids spans over 160 million years from the Middle Jurassic to the beginning of the Pleistocene, about 2.13–2 million years ago.
The Allen Formation is a geological formation in Argentina whose strata date back to the Late Cretaceous (middle Campanian to early Maastrichtian. Dinosaur remains are among the fossils that have been recovered from the formation. Indeterminate chelid remains and other vertebrates have also been discovered in this formation.
Nevobatrachus gracilis is the only species in the extinct genus Nevobatrachus, a genus of prehistoric frogs. The original generic name of this frog was Cordicephalus Nevo (1968); however, this generic name turned out to be preoccupied by a cestode genus Cordicephalus Wardle, McLeod & Stewart (1947), which remains nomenclaturally available in spite of being considered a junior synonym of the diphyllobothriid genus Pyramicocephalus. Mahony (2019) coined a replacement name Nevobatrachus. Fossils of N. gracilis were found in a lacustrine deposit in Makhtesh Ramon called "Amphibian Hill" and it is believed they lived during the Lower Cretaceous.
Rhadinosteus parvus is an extinct species of prehistoric frogs that lived during the Late Jurassic. Fossils of the species were found at the Rainbow Park site in Utah's Dinosaur National Monument, from several slabs of rock which contain multiple partial specimens, from sediments belonging to the Morrison Formation. R. parvus was likely a member of Pipoidea and may have been a member of the family Rhinophrynidae.
Vulcanobatrachus is an extinct genus of fossil frog. The genus contains the single species Vulcanobatrachus mandelai found at Marydale, South Africa, described in 2005 and named after Nelson Mandela. The genus owes its name to the fact that fossils were recovered from an extinct volcanic crater lake of Late Cretaceous age. The fossil frogs are assumed to have died following a limnic eruption (a degassing event possibly of CO2) by the volcano.
Thoraciliacus rostriceps is an extinct species of frog from the Cretaceous period and the only species of the genus Thoraciliacus, which is classified in the unranked clade Pipimorpha. Fossils of T. rostriceps were found in Makhtesh Ramon, Negev Desert, Israel and it is believed they lived during the Barremian. Other fossils have been found near Marydale, South Africa in an Upper Cretaceous lake.
Crossognathiformes is an extinct order of ray-finned fish that lived from the Late Jurassic to the Eocene. Its phylogenetic placement is disputed; some authors have recovered it as part of the teleost stem group, while others place it in a basal position within crown group Teleostei.
Elasmaria is a clade of ornithopods known from Cretaceous deposits in South America, Antarctica, and Australia that contains many bipedal ornithopods that were previously considered "hypsilophodonts".
The Calyptocephalellidae are a family of toads found in Chile containing two living genera, Calyptocephalella and Telmatobufo.
Palaeobatrachidae is an extinct family of frogs known from the Late Cretaceous to the Pleistocene primarily of Europe. They were highly adapted to aquatic life, like other members of the Pipimorpha. The oldest undoubted records of the family are from the lower Campanian of France. By far the most abundant genus is Palaeobatrachus, known from the Eocene to Pleistocene of Europe, with most other named genera in the family synonymised with it, the only exception being Albionbatrachus, which is distinguished from Palaeobatrachus by characters of its frontoparietals. The youngest fossils of Palaeobatrachus date to around 500,000 years ago, during the Middle Pleistocene after which they likely became extinct due to increasing aridity and freezing temperatures during the ice ages. Fossils of indeterminate palaeobatrachids are also known from the Pliocene and Early Pleistocene of Western Siberia.
The Cañadón Asfalto Basin is an irregularly shaped sedimentary basin located in north-central Patagonia, Argentina. The basin stretches from and partly covers the North Patagonian Massif in the north, a high forming the boundary of the basin with the Neuquén Basin in the northwest, to the Cotricó High in the south, separating the basin from the Golfo San Jorge Basin. It is located in the southern part of Río Negro Province and northern part of Chubut Province. The eastern boundary of the basin is the North Patagonian Massif separating it from the offshore Valdés Basin and it is bound in the west by the Patagonian Andes, separating it from the small Ñirihuau Basin.
The Huitrera Formation is a geological formation in the Neuquén Basin in northern Patagonian Argentina whose strata date back to the Early Eocene of the Paleogene, or Casamayoran in the South American land mammal age classification.
Patagopelta is an extinct genus of nodosaurine dinosaur from the Late Cretaceous Allen Formation of Argentina. The genus contains a single species, P. cristata, known from a partial skeleton. Patagopelta is a very small ankylosaur, comparable in size to the dwarf nodosaurid Struthiosaurus, about 2 m (6.6 ft) long.
