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.
Mammaliaformes is a clade that contains the crown group mammals and their closest extinct relatives; the group radiated from earlier probainognathian cynodonts. It is defined as the clade originating from the most recent common ancestor of Morganucodonta and the crown group mammals; the latter is the clade originating with the most recent common ancestor of extant Monotremata, Marsupialia, and Placentalia. Besides Morganucodonta and the crown group mammals, Mammaliaformes includes Docodonta and Hadrocodium.
Tritylodontidae is an extinct family of small to medium-sized, highly specialized mammal-like cynodonts, with several mammalian traits including erect limbs, endothermy and details of the skeleton. They were the last-known family of the non-mammaliaform synapsids, persisting into the Early Cretaceous.
Docodon is an extinct docodont mammaliaform from the Late Jurassic of western North America. It was the first docodont to be named.
Morganucodonta is an extinct order of basal Mammaliaformes, a group including crown-group mammals (Mammalia) and their close relatives. Their remains have been found in Southern Africa, Western Europe, North America, India and China. The morganucodontans were probably insectivorous and nocturnal, though like eutriconodonts some species attained large sizes and were carnivorous. Nocturnality is believed to have evolved in the earliest mammals in the Triassic as a specialisation that allowed them to exploit a safer, night-time niche, while most larger predators were likely to have been active during the day.
Kuehneotherium is an early mammaliaform genus, previously considered a holothere, that lived during the Late Triassic-Early Jurassic Epochs and is characterized by reversed-triangle pattern of molar cusps. Although many fossils have been found, the fossils are limited to teeth, dental fragments, and mandible fragments. The genus includes Kuehneotherium praecursoris and all related species. It was first named and described by Doris M. Kermack, K. A. Kermack, and Frances Mussett in November 1967. The family Kuehneotheriidae and the genus Kuehneotherium were created to house the single species Kuehneotherium praecursoris. Modeling based upon a comparison of the Kuehneotherium jaw with other mammaliaforms indicates it was about the size of a modern-day shrew between 4 and 5.5 g at adulthood.
Anoualerpeton is an extinct genus of lissamphibian in the family Albanerpetontidae. It is the oldest and most primitive albanerpetontid known. Fossils have been found of two different species, Anoualerpeton priscus from the Middle Jurassic (Bathonian) aged Forest Marble and Kilmaluag formations of England and Scotland, and Anoualerpeton unicus from Late Jurassic-Early Cretaceous (Tithonian-Berriasian) Ksar Metlili Formation of Morocco. A. unicus is the only named albanerpetontid from Gondwana.
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.
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.
The Kilmaluag Formation is a Middle Jurassic geologic formation in Scotland. It was formerly known as the Ostracod Limestone for preserving an abundance of fossil freshwater/low salinity ostracods. Gastropods, bivalves, trace fossil burrows, and vertebrate fossil remains have also been recorded from the formation. Vertebrate fossils include fish, crocodylomorphs, mammals, small reptiles, amphibians, theropod and sauropod dinosaurs and pterosaurs.
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.
Wareolestes rex is a mammaliaform from the Middle Jurassic (Bathonian) rocks of England and Scotland. It was originally known from isolated teeth from England, before a more complete jaw with teeth was found in the Kilmaluag Formation of Skye, Scotland.
Palaeoxonodon is an extinct genus of cladotherian mammal from the Middle Jurassic of England and Scotland.
Vilevolodon is an extinct, monotypic genus of volant, arboreal euharamiyids from the Oxfordian age of the Late Jurassic of China. The type species is Vilevolodon diplomylos. The genus name Vilevolodon references its gliding capabilities, Vilevol, while don is a common suffix for mammalian taxon titles. The species name diplomylos refers to the dual mortar-and-pestle occlusion of upper and lower molars observed in the holotype; diplo, mylos.
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.
Bocaconodon is an early mammaliaform genus that lived during the Pliensbachian of Mexico. The type and only species, Bocaconodon tamaulipensis, was named and described in 2008. It is known from a single specimen, a partial right dentary bone preserving two nearly complete molar teeth and the rear portion of a third molar. The specimen was found at the Huizachal Canyon locality, "a Pliensbachian floodplain siltstone in the La Boca Formation".
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.
Michael Waldman is a British palaeontologist known for his work on fossil fish, mammals, and reptiles. He also discovered the globally important fossil site of Cladach a'Ghlinne, near Elgol on the Isle of Skye, Scotland. This site exposes the Kilmaluag Formation and provides a valuable record of Middle Jurassic ecosystems. During the 1970s he visited the site several times with fellow palaeontologist Robert Savage. The fossil turtle Eileanchelys waldmani was named after Michael in recognition of his notable contribution to palaeontology.
Ceoptera is an extinct genus of darwinopteran pterosaur from the Middle Jurassic Kilmaluag Formation of Scotland. The genus contains a single species, C. evansae, known from a partial skeleton.It is the only pterosaur from Kilmaluag Formation. Ceoptera represents the second pterosaur named from Scotland, after Dearc in 2022.
