The family Alligatoridae of crocodylians includes alligators, caimans and their extinct relatives.
Ephedraceae is a family of gymnosperms belonging to Gnetophyta, it contains only a single extant genus, Ephedra, as well as a number of extinct genera from the Early Cretaceous.
Melanosuchus is a genus of caiman. The black caiman of South America is the sole extant (living) species, and is the largest living member of the subfamily Caimaninae, as well as the entire alligator family Alligatoridae.
Iguania is an infraorder of squamate reptiles that includes iguanas, chameleons, agamids, and New World lizards like anoles and phrynosomatids. Using morphological features as a guide to evolutionary relationships, the Iguania are believed to form the sister group to the remainder of the Squamata, which comprise nearly 11,000 named species, roughly 2000 of which are iguanians. However, molecular information has placed Iguania well within the Squamata as sister taxa to the Anguimorpha and closely related to snakes. The order has been under debate and revisions after being classified by Charles Lewis Camp in 1923 due to difficulties finding adequate synapomorphic morphological characteristics. Most Iguanias are arboreal but there are several terrestrial groups. They usually have primitive fleshy, non-prehensile tongues, although the tongue is highly modified in chameleons. The group has a fossil record that extends back to the Early Jurassic. Today they are scattered occurring in Madagascar, the Fiji and Friendly Islands and Western Hemisphere.
Crosbysaurus is a genus of extinct archosauromorph that lived in the Late Triassic of Arizona, New Mexico, North Carolina, Texas, and Utah. It is known from the Chinle Formation and Dockum Group rock units from the southwestern United States. The type species is C. harrisae, and the only known material includes teeth. 11 specimens are known, each including a single tooth.
Orycteocetus is an extinct genus of sperm whale from the Miocene of the northern Atlantic Ocean.
Rhizocyon is an early member of the subfamily Borophaginae, an extinct subgroup of canids that were endemic to western North America during the Oligocene epoch, living from ~31—24.5 Ma., existing for approximately 6.5 million years.
Eocaiman is an extinct genus of caiman containing species living from the Early Paleocene to Miocene in what is now Argentina, Itaboraí Formation of Brazil and Colombia. Eocaiman contains three described species: E. cavernensis, E. palaeocenicus, and E. itaboraiensis, and is typically recovered as one of the more basal members of Caimaninae. Notocaiman was synonymized with Eocaiman paleocenicus in 2022.
Brachyuranochampsa is an extinct genus of crocodilian.
Dollosuchoides, colloquially known as the Crocodile of Maransart, is an extinct monospecific genus of gavialoid crocodilian, traditionally regarded as a member of the subfamily Tomistominae. Fossils have been found in the Brussel Formation of Maransart, Belgium and date back to the middle Eocene.
Crocodyliformes is a clade of crurotarsan archosaurs, the group often traditionally referred to as "crocodilians". They are the first members of Crocodylomorpha to possess many of the features that define later relatives. They are the only pseudosuchians to survive the K-Pg extinction event.
Paratomistoma is an extinct monospecific genus of gavialoid crocodylian. It is based on the holotype specimen CGM 42188, a partial posterior skull and lower jaw discovered at Wadi Hitan, Egypt, in Middle Eocene-age rocks of the Gehannam Formation. The skull is unfused but considered morphologically mature. Paratomistoma was named in 2000 by Christopher Brochu and Philip Gingerich; the type species is P. courti in honor of Nicholas Court, who found CGM 42188. They performed a phylogenetic analysis and found Paratomistoma to be a derived member of Tomistominae, related to the false gharial. It may have been a marine or coastal crocodilian.
"Crocodylus" affinis is an extinct species of crocodyloid from the Eocene of Wyoming. Fossils were first described from the Bridger Formation by American paleontologist Othniel Charles Marsh in 1871. Marsh described the species, along with every other species of crocodyloid in the Bridger Formation, under the genus Crocodylus. The known specimen of "Crocodylus" affinis is a skull found at Grizzly Buttes, Wyoming, measuring 13 inches in length on the upper surface. Recent phylogenetic studies of crocodyloids show that "C." affinis is not a species of Crocodylus, but a genus has not yet been erected to include the species. Other Bridger species such as Crocodylus clavis and Brachyuranochampsa zangerli have been synonymized with "C." affinis.
"Crocodylus" acer is an extinct species of crocodyloid from the Eocene of Utah. A single well preserved skull was described by paleontologist Edward Drinker Cope in 1882 and remains the only known fossil of the species. It was found from the Wasatchian-age Green River Formation. "C." acer had a long, narrow snout and a low, flattened skull.
Tzaganosuchus is an extinct monospecific genus of fossil crocodile from the Gobi Desert of southern/southeastern Mongolia. The type and only known species for this genus, Tzaganosuchus infansis was discovered during a joint paleontological expedition conducted by the Soviet Union and Mongolia. That same expedition also described several other reptiles including several species of Shamosuchus and the archosauromorph genus Irenosaurus. The prefix of the name "Tzaganosuchus" is a Mongol word derived from the locality where its fossils were first found: the Tsagan Khushu Quarry, which dates to the Paleogene epoch and is part of the Naran-Bulak Formation. The suffix suchus is a Latin word for crocodile.
Tomistoma cairense is an extinct species of gavialoid crocodilian from the Lutetian stage of the Eocene era. It lived in North East Africa, especially Egypt. Remains of T. cairense have been found in the Mokattam Formation, in Mokattam, Egypt. Tomistoma cairense did not have a Maxilla process within their lacrimal gland, whereas all extant (living) crocodilians do.
The Micropholidae are an extinct family of dissorophoid euskelian temnospondyls known from Late Carboniferous to Early Triassic strata in the United States and South Africa.
Australopristis is an extinct genus of rajiform ray from the late Cretaceous epoch. Its name is derived from the Latin for "southern" and the Greek for "saw". It is known from a single species, A. wiffeni named for the late prominent fossil hunter Joan Wiffen. This species is currently known only from rostral teeth found at Mangahouanga stream and East Wing, Haumuri bluff, New Zealand. It's rostral teeth possess a smooth root which makes it unique among Sclerorhynchids. Rostral teeth appear to vary in morphology according to position and ontogenetic stage. Unlike the related Onchopristis and Atlanticopristis, it lives in a marine rather than fluvial environment and likely preferred cooler waters.
Kranosaura is an extinct genus of archosauriform reptile from the Late Triassic Upper Maleri Formation of India. It contains a single species, K. kuttyi, described in 2021 by Sterling Nesbitt et al. It had an unusually domed head reminiscent of the later pachycephalosaurian dinosaurs in an example of convergent evolution, similar to that of Triopticus. Kranosaura was the sister taxon to Triopticus, with which it forms the clade Protopyknosia. The genus is based on two domes of 9 centimetres (3.5 in) long, discovered by T. S. Kutty in the 1990s.
Mcdonaldocnus is an extinct genus of nothrotheriid ground sloths that lived during the Middle Miocene and Early Pliocene of what is now Bolivia and Argentina. It was originally placed in the genus Xyophorus but was subsequently recognized as a distinct genus by Gaudin and colleagues in 2022. The authors reassigned the material of "Xyophorus" bondesioi, Xyophorusvillarroeli and Xyophorus sp. to Mcdonaldocnus. Fossils of Mcdonaldocnus have been found in the Cerro Azul Formation of Argentina.
