The Trachypachidae are a family of beetles that generally resemble small ground beetles, but that are distinguished by the large coxae of their rearmost legs. There are only six known extant species in the family, with four species of Trachypachus found in northern Eurasia and northern North America, and two species of Systolosoma in Chile and Argentina. They were much more diverse in the past, with dozens of described species from the Mesozoic.
Temnodontosaurus is an extinct genus of ichthyosaur from the Early Jurassic period. They lived between 200 and 175 million years ago (Hettangian-Toarcian) in what is now Western Europe and possibly Chile. It lived in the deeper areas of the open ocean. University of Bristol paleontologist Jeremy Martin described the genus Temnodontosaurus as "one of the most ecologically disparate genera of ichthyosaurs," although the number of valid Temnodontosaurus species has varied over the years.
Emausaurus is a genus of thyreophoran or armored dinosaur from the Early Jurassic. Its fossils have been found in Mecklenburg-Vorpommern, northern Germany. Emausaurus is the only known Toarcian thyreophoran, as well as the only dinosaur from the zone of the same age with a formal name.
Ohmdenosaurus is a genus of sauropod dinosaur that lived during the Early Jurassic epoch in what is now Germany. The only specimen – a tibia (shinbone) and ankle – was discovered in rocks of the Posidonia Shale near Holzmaden. The fossil was originally identified as a plesiosaur. Exhibited in a local museum, the Urweltmuseum Hauff, it caught the attention of German paleontologist Rupert Wild, who recognized it as the remains of a sauropod. Wild named Ohmdenosaurus in a 1978 publication, the only species is Ohmdenosaurus liasicus.
Elasmosauridae is an extinct family of plesiosaurs, often called elasmosaurs. They had the longest necks of the plesiosaurs and existed from the Hauterivian to the Maastrichtian stages of the Cretaceous, and represented one of the two groups of plesiosaurs present at the end of the Cretaceous alongside Polycotylidae. Their diet mainly consisted of crustaceans and molluscs.
Stenopterygius is an extinct genus of thunnosaur ichthyosaur known from Europe. This genus of ichthyosaur was about 3–4 meters long and weighed 150–310 kg (330–680 lb).
Rhomaleosaurus is an extinct genus of Early Jurassic rhomaleosaurid pliosauroid known from Northamptonshire and from Yorkshire of the United Kingdom. It was first named by Harry Seeley in 1874 and the type species is Rhomaleosaurus cramptoni. It was one of the earliest large marine reptile predators which hunted in the seas of Mesozoic era, with the type species R. cramptoni measuring 6.7–7 metres (22–23 ft) long and weighing 2.1 metric tons. Like other pliosaurs, Rhomaleosaurus fed on ichthyosaurs, ammonites and other plesiosaurs.
Microcleidus is an extinct genus of sauropterygian reptile belonging to the Plesiosauroidea. The species has 40 neck vertebrae and a short tail of 28 vertebrae. Fossils of the genus have been found in France, the Posidonia Shale in Germany and Luxembourg, and the Alum Shale Formation of England.
Excalibosaurus is a monotypic genus of marine prehistoric reptiles (ichthyosaurs) that lived during the Sinemurian stage of the Early Jurassic period in what is now England. It is characterized by the extreme elongation of the rostrum, with the lower jaw about three-fourths of the length of the upper jaw, giving the animal a swordfish-like look. The only known species is Excalibosaurus costini.
Brancasaurus is a genus of plesiosaur which lived in a freshwater lake in the Early Cretaceous of what is now North Rhine-Westphalia, Germany. With a long neck possessing vertebrae bearing distinctively-shaped "shark fin"-shaped neural spines, and a relatively small and pointed head, Brancasaurus is superficially similar to Elasmosaurus, albeit smaller in size at 3.26 metres (10.7 ft) in length as a subadult.
Mystriosaurus is an extinct genus of teleosaurid crocodyliform from the Early Jurassic (Toarcian). Fossil specimens have been found in the Whitby Mudstone of England and Posidonia Shale of Germany. The only known species, M. laurillardi, exceeded 4 metres (13 ft) in length.
Hauffiosaurus is an extinct genus of Early Jurassic pliosaurid plesiosaur known from Holzmaden of Germany and from Yorkshire of the United Kingdom. It was first named by Frank Robin O’Keefe in 2001 and the type species is Hauffiosaurus zanoni. In 2011, two additional species were assigned to this genus: H. longirostris and H. tomistomimus.
Eurycleidus is an extinct genus of large-bodied rhomaleosaurid known from the Early Jurassic period of the United Kingdom. It contains a single species, E. arcuatus. Like other plesiosaurs, Eurycleidus probably lived on a diet of fish, using its sharp needle-like teeth to catch prey. Its shoulder bones were fairly large, indicating a powerful forward stroke for fast swimming.
Seeleyosaurus is an extinct genus of plesiosaur that was initially placed within the genus Plesiosaurus in 1895 and was given its own genus in 1940. Two species were known: the type, S. guilelmiimperatoris, and the now obsolete species S. holzmadensis, which has since been absorbed into S. guilelmiimperatoris. It was a relatively small plesiosaur, measuring 2.9–3.8 m (9.5–12.5 ft) long and weighing 250 kg (550 lb). The holotype was MB.R.1992, a large almost complete skeleton from the Upper Lias (Toarcian) Lias Group Formations of Württemberg, Germany. There seems to be the impression of a rhomboidal flap of skin in a vertical plane; if so, many plesiosaurs may have been equipped in this way. The holotype was destroyed in 1945 (WWII) and only a cast exists today. A second specimen, preserved in 3D, has survived until today. It was once the holotype of the now obsolete species S. holzmadensis.
The Posidonia Shale geologically known as the Sachrang Formation, is an Early Jurassic (Toarcian) geological formation of southwestern and northeast Germany, northern Switzerland, northwestern Austria, southern Luxembourg and the Netherlands, including exceptionally well-preserved complete skeletons of fossil marine fish and reptiles. The Posidonienschiefer, as German paleontologists call it, takes its name from the ubiquitous fossils of the oyster-related bivalve Posidonia bronni that characterize the mollusk faunal component of the formation.
Trachymetopon is an extinct genus of prehistoric coelacanth from the Jurassic of Europe. Fossils have been found in the Early Jurassic Posidonia Shale of Germany the Middle Jurassic Marnes de Dives of France, and probably the Late Jurassic Kimmeridge Clay of England. Only one species has been named, Trachymetopon liassicum, described by Henning in 1951 from an almost complete specimen found in the Lower Toarcian of Ohmden in Baden-Württemberg. Another specimen is known from the same site, and two older specimens come from the Sinemurian of Holzmaden. The holotype of this species is 1.6 metres in length. A giant specimen of an undetermined species of Trachymetopon found at the Middle Jurassic Falaises des Vaches Noires of Normandy. This specimen, composed of a 53 cm long palatoquadrate, belongs to an individual 4 metres (13 ft) in length. A basisphenoid found in a museum in Switzerland that likely originates from the same locaity probably belonged to an individual around 5 m (16 ft) long, making Trachymetopon the largest of all coelacanths alongside Mawsonia. A study published in 2015 revealed that this coelacanth belongs to the Mawsoniidae. Trachymetopon is one of the few known mawsoniids to have been exclusively marine, while most of the other members of the group have lived in fresh and brackish waters.
Meyerasaurus is an extinct genus of rhomaleosaurid known from Holzmaden, Baden-Württemberg of southwestern Germany.
The Sachrang Formation or "Posidonienschiefer" Formation is a geological formation of southwestern Germany, northern Switzerland, northwestern Austria, southeast Luxembourg and the Netherlands, that spans about 3 million years during the Early Jurassic period. It is known for its detailed fossils, especially sea fauna, listed below. Composed mostly by black shale, the formation is a Lagerstätte, where fossils show exceptional preservation, with a thickness that varies from about 1 m to about 40 m on the Rhine level, being on the main quarry at Holzmaden between 5 and 14 m. Some of the preserved material has been transformed into fossil hydrocarbon Jet, specially wood remains, used for jewelry. The exceptional preservation seen on the Posidonia Shale has been studied since the late 1800s, finding that a cocktail of chemical and environmental factors let to such an impressive conservation of the marine fauna. The most common theory is the changes in the oxygen level, where the different anoxic events of the Toarcian left oxygen-depleted bottom waters, with the biota dying and falling to the bottom without any predator able to eat the dead bodies.
Fulgoridiidae are an extinct family of Mesozoic planthoppers. They are the earliest group of planthoppers known, and appear to be a paraphyletic assemblage ancestral to living planthoppers. The majority of known members of the family lived in the Jurassic period, though the group also includes one Cretaceous taxon. All currently known species are from Eurasia.
Magnipterygius is an extinct genus of primitive ichthyosaur found in the Early Jurassic Posidonia Shale of Dotternhausen, Germany. The holotype specimen is SMNS96922, a nearly complete articulated skeleton. This genus is well known as a small-sized Ichthyosaur, of around 120 cm length, making it the second genus of that size after the Triassic. Due to the similarities with the genus Stenopterygius it has been classified as a member of the family Stenopterygiidae.
