Castorocauda is an extinct, semi-aquatic, superficially otter-like genus of docodont mammaliaforms with one species, C. lutrasimilis. It is part of the Yanliao Biota, found in the Daohugou Beds of Inner Mongolia, China dating to the Middle to Late Jurassic. It was part of an explosive Middle Jurassic radiation of Mammaliaformes moving into diverse habitats and niches. Its discovery in 2006, along with the discovery of other unusual mammaliaforms, disproves the previous hypothesis of Mammaliaformes remaining evolutionarily stagnant until the extinction of the non-avian dinosaurs.
Docodonta is an order of extinct Mesozoic mammaliaforms. They were among the most common mammaliaforms of their time, persisting from the Middle Jurassic to the Early Cretaceous across the continent of Laurasia. They are distinguished from other early mammaliaforms by their relatively complex molar teeth. Docodont teeth have been described as "pseudotribosphenic": a cusp on the inner half of the upper molar grinds into a basin on the front half of the lower molar, like a mortar-and-pestle. This is a case of convergent evolution with the tribosphenic teeth of therian mammals. There is much uncertainty for how docodont teeth developed from their simpler ancestors. Their closest relatives may have been certain Triassic "symmetrodonts", namely Woutersia, Delsatia, and Tikitherium.
The Australosphenida are a clade of mammals, containing mammals with tribosphenic molars, known from the Jurassic to Mid-Cretaceous of Gondwana. Although they have often been suggested to have acquired tribosphenic molars independently from those of Tribosphenida, this has been disputed. Fossils of australosphenidans have been found from the Jurassic of Madagascar and Argentina, and Cretaceous of Australia and Argentina. Monotremes have also been considered a part of this group in many studies, but this is also disputed.
Docodon is an extinct docodont mammaliaform from the Late Jurassic of western North America. It was the first docodont to be named.
Chororapithecus is an extinct great ape from the Afar region of Ethiopia roughly 8 million years ago during the Late Miocene, comprising one species, C. abyssinicus. It is known from 9 isolated teeth discovered in a 2005–2007 survey of the Chorora Formation. The teeth are indistinguishable from those of gorillas in terms of absolute size and relative proportions, and it has been proposed to be an early member of Gorillini. However, this is controversial given the paucity of remains, and notable anatomical differences between Chororapithecus and gorilla teeth. The Kenyan ape Nakalipithecus has been proposed to be an ancestor of Chororapithecus or at least closely related. If correct, they would be the only identified fossil members of any modern non-human great ape lineage, and would push the gorilla–human last common ancestor from 8 million years ago to 10 million years ago. The teeth are adapted for processing tough plant fibres as well as hard, brittle food, and the formation is thought to represent a forested lakeside habitat.
Paritatodon is an extinct mammaliaform which existed in Kyrgyzstan and England during the Jurassic period. It was originally the holotype specimen of Shuotherium kermacki, but Martin and Averianov (2010) argued that it resembled the genus Itatodon (Docodonta) and so renamed it Paritatodon.
Reigitherium was a mammal that lived during the Late Cretaceous, in the. Its fossils have been found in the Los Alamitos and the La Colonia Formations of Argentina.
Haldanodon is an extinct docodont mammaliaform which lived in the Upper Jurassic. Its fossil remains have been found in Portugal, in the well-known fossil locality of Guimarota, which is in the Alcobaça Formation. It may have been a semi-aquatic burrowing insectivore, similar in habits to desmans and the platypus. Several specimens are known, include a partial skeleton and well-preserved skulls.
Agilodocodon was a genus of shrew-sized docodont from the Middle Jurassic, believed to be the earliest known tree-climbing mammaliaform. It contains one species, A. scansorius.
Ichthyoconodon is an extinct genus of eutriconodont mammal from the Lower Cretaceous of Morocco. It is notable for having been found in a unique marine location, and the shape of its teeth suggests an unusual, potentially fish-eating ecological niche. Analysis suggests it is part of a group of gliding mammals that includes Volaticotherium.
Tashkumyrodon is an extinct mammaliaform from the Middle Jurassic (Callovian) Balabansai Formation of Kyrgyzstan It is named after the town of Tash-Kömür, near where the original specimen was found. It belongs to the order Docodonta and is closely related to Sibirotherium and Tegotherium. There is only one species currently known, Tashkumyrodon desideratus.
Borealestes is a genus of docodontan from the Middle Jurassic of Britain, first discovered on the Isle of Skye near the village of Elgol. It was the earliest mammaliaform from the Mesozoic found and named in Scotland. A second species and was later found in other Middle Jurassic sites in England, but is now shown to be a different genus. A new species, B. cuillinensis was named in 2021, also from Skye.
Tikitherium is an extinct genus of mammaliaforms from India, known from a single upper tooth. Originally argued to be a primitive mammaliaform from the Late Triassic, a 2024 study argued that it actually represented the remains of a shrew from the Neogene. Tikitherium refers to Tiki, the village located near the Tiki Formation where the specimen was originally thought to have come from, and therium is Greek for “Beast”. The species was named copei in honor of Edward Drinker Cope for his pioneering discoveries towards understanding mammalian molars.
Peraiocynodon is an extinct mammaliaform from the order Docodonta, found in the Middle Jurassic rocks of the United Kingdom. It is only known from isolated molar teeth found in the mammal bed at Kirtlington cement quarry in Oxfordshire, England.
Cyrtlatherium is a dubious genus of extinct docodontan mammaliaform from the Middle Jurassic rocks of Oxfordshire, England. As it is only known from a few isolated molar teeth, there is disagreement about whether Cyrtlatherium is a separate genus, or whether it is a synonym and the molar teeth are the deciduous teeth of another genus of docodont.
Gondtherium is a genus of extinct mammaliaform from the Kota Formation in India. It was considered a docodontan by those who described it, but it remains unclear if this is the case.
Itatodon is an extinct genus of primitive mammaliaforms known from the Bathonian aged Itat Formation of Russia. The genus is named after the formation, with the species being named after Leonid Petrovich Tatarinov who described the first docodont from Asia. It is known from a holotype right lower molar and referred isolated right lower molar and fragment of the left lower molar. When it was first described, it was thought to be a docodontan, but one recent phylogenetic studies have assigned it, along with its close relative Paritatodon to Shuotheriidae, while others continue to consider it a docodont.
Denise Sigogneau-Russell is a French palaeontologist who specialises in mammals from the Mesozoic, particularly from France and the UK. She is currently based at the Muséum National d'Histoire Naturelle.
Dobunnodon its an extinct genus of docodont from the Middle Jurassic (Bathonian) Forest Marble Formation of England, first discovered in Oxfordshire near the village of Kirtlington. The type species, D. mussettae, was originally named as a species of Borealestes in 2003.
Sibirotherium is an extinct genus of docodont mammaliaform. It is known from only a single named species, Sibirotherium rossicum, known from jaw fragments and teeth found in the Early Cretaceous (Aptian) aged Ilek Formation in western Siberia, alongside Khorotherium also from Siberia, it is one of the youngest docodonts.
