| Lorrainosaurus | |
|---|---|
 | |
| Fossils of holotype (MNHNL BU159) and skeletal reconstruction of L. keileni | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Superorder: | † Sauropterygia |
| Order: | † Plesiosauria |
| Family: | † Pliosauridae |
| Genus: | † Lorrainosaurus |
| Species: | †L. keileni |
| Binomial name | |
| †Lorrainosaurus keileni Sachs et al., 2023 | |
| Synonyms | |
| |
Lorrainosaurus is an extinct genus of thalassophonean pliosaurid from the Middle Jurassic of Lorraine, France. [2]
The holotype specimen (MNHNL BU159) was discovered during a temporary excavation for a roadway upgrade between the Montois-la-Montagne and Sainte-Marie-aux-Chênes communes in Lorraine, France. The remains consisted of a near-complete mandible, coracoid shoulder bone, a tooth, and fragments of the upper jaw and front limb. They specifically originated from a section of the Marnes de Gravelotte, a marl deposit dated to the Bajocian stage of the Middle Jurassic around 168 mya. The specimen first came under the study of paleontologist Pascal Godefroit in 1994, who described it as a new species of Simolestes and assigned the name S. keileni. [2]
The generic identification was doubted by the PhD thesis of Noè (2001), [3] but it was not until at least 2021 that the holotype began to be rigorously reexamined by Sven Sachs of the Bielefeld Natural History Museum. [4] Sachs published his results in a 2023 multi-authored study, which found that MNHNL BU159 belonged to a more derived lineage than Simolestes. This thus warranted a new genus, which they named Lorrainosaurus, a portmanteau of the type locality Lorraine and Ancient Greek σαῦρος (sauros, "reptile"). [2]
Lorrainosaurus was a fairly small pliosaur. When extrapolating the length of the holotype's full-length mandible (133 centimeters (52 in)) to the proportions of the closely related Stenorhynchosaurus , which is represented by a near-complete skeleton with a mandible close to one-third of the total animal's length, [lower-alpha 1] a total length of 4.66 meters (15.3 ft) for L. keileni can be estimated. [2] [5]
Kronosaurus is an extinct genus of short-necked pliosaurs that lived during the Early Cretaceous period in what is now Australia. It is a monotypic genus with one species K. queenslandicus, described in 1924 from the Toolebuc Formation in Queensland, Australia. With traditionally attributed fossils indicating a total length of up to 10 meters (33 ft), Kronosaurus may have been among the largest pliosaurs.
Pliosauroidea is an extinct clade of plesiosaurs, known from the earliest Jurassic to early Late Cretaceous. They are best known for the subclade Thalassophonea, which contained crocodile-like short-necked forms with large heads and massive toothed jaws, commonly known as pliosaurs. More primitive non-thalassophonean pliosauroids resembled plesiosaurs in possessing relatively long necks and smaller heads. They originally included only members of the family Pliosauridae, of the order Plesiosauria, but several other genera and families are now also included, the number and details of which vary according to the classification used.
Liopleurodon is an extinct genus of large, carnivorous marine reptile belonging to the Thalassophonea, a clade of short-necked pliosaurid plesiosaurs. Liopleurodon lived from the Callovian Stage of the Middle Jurassic to the Kimmeridgian stage of the Late Jurassic Period. It was the apex predator of the Middle to Late Jurassic seas that covered Europe. The largest species, L. ferox, is estimated to have grown up to 6.6 metres (22 ft) in length based on the largest known skull.
Peloneustes is a genus of pliosaurid plesiosaur from the Middle Jurassic of England. Its remains are known from the Peterborough Member of the Oxford Clay Formation, which is Callovian in age. It was originally described as a species of Plesiosaurus by palaeontologist Harry Govier Seeley in 1869, before being given its own genus by naturalist Richard Lydekker in 1889. While many species have been assigned to Peloneustes, P. philarchus is currently the only one still considered valid, with the others moved to different genera, considered nomina dubia, or synonymised with P. philarchus. Some of the material formerly assigned to P. evansi have since been reassigned to "Pliosaurus" andrewsi. Peloneustes is known from many specimens, including some very complete material.
Pliosaurus is an extinct genus of thalassophonean pliosaurid known from the Kimmeridgian and Tithonian stages of Europe and South America. Their diet would have included fish, cephalopods, and marine reptiles. This genus has contained many species in the past but recent reviews found only six to be valid, while the validity of two additional species awaits a petition to the International Code of Zoological Nomenclature. Currently, P. brachyspondylus and P. macromerus are considered dubious, while P. portentificus is considered undiagnostic. Most European species of Pliosaurus measured around 8 metres (26 ft) long and weighed about 5 metric tons, but P. rossicus and P. funkei would have been one of the largest plesiosaurs of all time, exceeding 10 metres (33 ft) in length. Species of this genus are differentiated from other pliosaurids based on seven autapomorphies, including teeth that are triangular in cross section.
Brachauchenius is an extinct genus of pliosaurid that lived in North America and Morocco during the Late Cretaceous.
Plesiosuchus is an extinct genus of geosaurine metriorhynchid crocodyliform known from the Late Jurassic of Dorset, England and possibly also Spain. It contains a single species, Plesiosuchus manselii.
Simolestes is an extinct pliosaurid genus that lived in the Middle to Late Jurassic. The type specimen, BMNH R. 3319 is an almost complete but crushed skeleton diagnostic to Simolestes vorax, dating back to the Callovian of the Oxford Clay formation, England. The genus is also known the Tithonian of India (S.indicus). The referral of this species to Simolestes is dubious, however. S.keileni from France was moved to the new genus Lorrainosaurus in 2023.
Eurysaurus is an extinct genus of plesiosaur, originally classed as a nothosaur, from the Early Jurassic of Echenoz-la-Meline, France, named in 1878. The type material, consisting of a cranium, teeth and five vertebrae, is now lost. The type species is E. raincourti, and a second species, E. schafferi, was named in 1924 but it has since been absorbed into the unrelated genus Germanosaurus.
Eromangasaurus is an extinct genus of elasmosaurid known from northern Queensland of Australia.
Pachycostasaurus is an extinct Pliosauroid from the Oxford Clay formation of Peterborough, England.
This timeline of plesiosaur research is a chronologically ordered list of important fossil discoveries, controversies of interpretation, taxonomic revisions, and cultural portrayals of plesiosaurs, an order of marine reptiles that flourished during the Mesozoic Era. The first scientifically documented plesiosaur fossils were discovered during the early 19th century by Mary Anning. Plesiosaurs were actually discovered and described before dinosaurs. They were also among the first animals to be featured in artistic reconstructions of the ancient world, and therefore among the earliest prehistoric creatures to attract the attention of the lay public. Plesiosaurs were originally thought to be a kind of primitive transitional form between marine life and terrestrial reptiles. However, now plesiosaurs are recognized as highly derived marine reptiles descended from terrestrial ancestors.
Megacephalosaurus is an extinct genus of short-necked pliosaur that inhabited the Western Interior Seaway of North America about 94 to 93 million years ago during the Turonian stage of the Late Cretaceous, containing the single species M. eulerti. It is named after its large head, which is the largest of any plesiosaur in the continent and measures up to 1.75 meters (5.7 ft) in length. Megacephalosaurus was one of the largest marine reptiles of its time with an estimated length of 6–9 meters (20–30 ft). Its long snout and consistently sized teeth suggest that it preferred a diet on smaller-sized prey.
Stenorhynchosaurus is an extinct genus of pliosaurid plesiosaurs which lived in the Early Cretaceous of South America. The type species and only known is Stenorhynchosaurus munozi. It was a medium-sized pliosaur, reaching an adult body length of 7 m (23 ft).
María Euridice Páramo Fonseca is a Colombian paleontologist and geologist. She has contributed to paleontology in Colombia in the fields of describing various Cretaceous reptiles, most notably the mosasaurs Eonatator and Yaguarasaurus, the ichthyosaur Kyhytysuka, and the plesiosaurs Leivanectes and Stenorhynchosaurus.
Acostasaurus is an extinct genus of possibly Thalassophonean pliosaurid known from the Barremian of the Paja Formation, Colombia. The type specimen, UNDG R-1000, is known from a near complete skull, and postcranial elements including a complete hindlimb and various vertebrae. The specimen has an estimated size of over 4 metres (13 ft) in length and 1 metric ton in body mass.
Sachicasaurus is an extinct genus of brachauchenine pliosaurid known from the Barremian of the Paja Formation, Altiplano Cundiboyacense in the Colombian Eastern Ranges of the Andes. The type species is S. vitae.
Monquirasaurus is an extinct genus of giant short-necked pliosaurs who lived during the Early Cretaceous (Aptian) in what is now Colombia. One species is known, M. boyacensis, described in 2021 from an almost complete fossil skeleton, discovered in 1977 in the town of Villa de Leyva, located in Boyacá. Published descriptions of the holotype specimen estimate that it should reach a total size approaching 8 m (26 ft) in length, making Monquirasaurus a large representative of the pliosaurids.
Eardasaurus is a genus of thalassophonean pliosaurid from the middle Jurassic Oxford Clay Formation. The animal would have measured over 4.7 m (15 ft) long and possessed a high amount of teeth relative to other pliosaurs. Its teeth show distinct ridges formed by the tooth enamel, some of which are very pronounced and similar to carinae, giving the teeth a cutting edge.
"Pliosaurus" andrewsi is an extinct species of pliosaurid plesiosaurs that lived during the Callovian stage of the Middle Jurassic, in what is now England. The only known fossils of this taxon were discovered in the Peterborough Member of the Oxford Clay Formation. Other attributed specimens have been discovered in various corners of Eurasia, but these are currently seen as indeterminate or coming from other taxa. The taxonomic history of this animal is quite complex, because several of its fossils were attributed to different genera of pliosaurids, before being concretely named and described in 1960 by Lambert Beverly Tarlo as a species of Pliosaurus. However, although the taxon was found to be valid, subsequent revisions found that it is not part of this genus, and therefore a taxonomic revision must be carried out on this species.
