| Alethodontus Temporal range: | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Chondrichthyes |
| Order: | Chimaeriformes |
| Family: | Myriacanthidae |
| Genus: | † Alethodontus Duffin, 1983 |
Alethodontus is an extinct genus of chimaera from the Hettangian stage of the Jurassic period. It is known from a single species, A. bavariensis, known from Germany. [1] [2]
Sinaspideretes is an extinct genus of turtle from the Late Jurassic of China, probably from the Shaximiao Formation. It is considered the earliest and most basal representative of the Trionychia, and is possibly the oldest known member of Cryptodira. In 2013, it was proposed that this animal and the genus Yehguia are in fact one and the same.
Steneosaurus is a dubious genus of teleosaurid crocodyliform from the Middle or Late Jurassic of France. The genus has been used as a wastebasket taxon for thalattosuchian fossils for over two centuries, and almost all known historical species of teleosauroid have been included within it at one point. The genus has remained a wastebasket, with numerous species still included under the label ‘Steneosaurus’, many of which are unrelated to each other.
Ferganoceratodus is a genus of prehistoric lungfish known from the Mesozoic of Asia. Based on morphological evidence, it was previously assumed to be a basal member of the Ceratodontiformes with no close relatives, but more recent studies incorporating both phylogenetic and morphological evidence have found it to be the sister group of the Neoceratodontidae.
Mioceratodus is an extinct genus of lungfish in the family Neoceratodontidae, which also contains the extant Queensland lungfish. It is known only from Oligocene and Miocene-aged sediments in Australia, although phylogenetic evidence supports it having first diverged from its closest relative, Neoceratodus, during the Late Jurassic or Early Cretaceous period.
Uluops is an extinct genus of paracryptodire turtle from the Late Jurassic (Tithonian) of North America. The type and only species is Uluops uluops, which is known from a single skull from the Morrison Formation.
The Ulan Malgait Formation is a Late Jurassic geologic formation in Mongolia. Dinosaur remains are among the fossils that have been recovered from the formation, although as of 2004 none have yet been referred to a specific genus.
Djupedalia is an extinct genus of cryptoclidid plesiosauroid plesiosaur known from the uppermost Jurassic of central Spitsbergen, Norway. It is named after Øystein Djupedal, the former Minister of Education and Research who helped fund the fossil excavation with a budget of 1.2 million Norwegian kroner.
Palvennia is an extinct genus of ophthalmosaurid ichthyosaurian known from the uppermost Jurassic of Central Spitsbergen, Norway. It was named for PalVenn, the Friends of the Palaeontological Museum in Oslo, whose expedition led to the discovery of the type specimen. Palvennia was a medium-sized ichthyosaur, measuring 3–4 m (9.8–13.1 ft) long. It is known from a single skull from the Slottsmøya Member of the Agardhfjellet Formation that measures 86 cm long. It is unusual in having a very short rostrum, similar to Ichthyosaurus breviceps. Because of this, the orbit seems very large, but this may be effected by crushing. The single and only known species is Palvennia hoybergeti Druckenmiller et al., 2012. In 2019, Palvennia was synonymized with Arthropterygius, though maintained as a separate species, by Nikolay Zverkov and Natalya Prilepskaya, although this synonymy was objected to later that same year by Lene Delsett and colleagues, who maintained that they were sufficiently different to warrant separate genera.
The Rabekke Formation is a geological formation dating to the latest Jurassic or earliest Cretaceous, around 146 to 145 million years ago. The formation crops out on the island of Bornholm, Denmark. Vertebrate fossils have been found in the formation.
The Robbedale Formation is a geological formation dating to the Berriasian stage of the Early Cretaceous, about 142 million years ago. It is on the island of Bornholm, Denmark.
Pygope is an extinct genus of brachiopods belonging to the family Pygopidae. These brachiopods lived in open sea from the Jurassic Period, Kimmeridgian age up to Cretaceous Period, Barremian age. Some of the species are characterised by a smaller or larger perforation through the entire shell in older specimens, while others just have a depression somewhere on the midline. Younger specimens of the perforated species develop a heart-shape and subsequently both extensions merge, thus encircling a central passage which is in fact entirely outside the shell.
Bienotheroides is an extinct genus of tritylodontid mammaliamorphs from the Jurassic of China and Mongolia. The genus contains five species, primarily known from cranial remains.
Kunminia is a genus of cynodont synapsids from the Early Jurassic (Sinemurian) Lufeng Formation of China.
Janusaurus is an extinct genus of ophthalmosaurid ichthyosaur from the Upper Jurassic Slottsmøya Member, Agardhfjellet Formation of Central Spitsbergen. The holotype consists of a partial skull and postcrania, and would have belonged to an individual measuring 3–4 m (9.8–13.1 ft) long. In 2019, Janusaurus was synonymized with Arthropterygius, though maintained as a separate species, by Nikolay Zverkov and Natalya Prilepskaya, although this synonymy was objected to later that same year by Lene Delsett and colleagues, who maintained that they were sufficiently different to warrant separate genera.
Pleurosternidae is an extinct family of freshwater turtles belonging to Paracryptodira. They are definitively known from the Late Jurassic to Early Cretaceous (Albian) of Western Europe and North America.
Synechodontiformes is an extinct order of prehistoric sharks, known from the Permian to the Paleogene. They are considered to be members of Neoselachii, the group that contains modern sharks and rays. Their placement in the group is uncertain, some authors have considered them to be galeomorph crown-group sharks, while others have considered them to represent a stem-group to modern sharks. They have sometimes been considered a paraphyletic grouping, but Klug (2010) recovered the group as monophyletic. Members of the clade are united by two synapomorphies, "pseudopolyaulacorhize tooth root pattern present; labial root depression in basal view present". The oldest possible member of the clade are teeth from the early Permian (Cisuralian) of the Ural Mountains.
Helochelydra is an extinct genus of extinct stem turtle known from the Early Cretaceous (Barremian) of the Isle of Wight, southern England.
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