Lusitanosaurus Temporal range: Late Sinemurian | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Reptilia |
Clade: | Archosauromorpha |
Genus: | † Lusitanosaurus |
Species: | †L. liasicus |
Binomial name | |
†Lusitanosaurus liasicus Lapparent & Zbyszewski, 1957 | |
Lusitanosaurus (meaning "Portuguese lizard") is a genus of reptile from the Sinemurian stage of Early Jurassic of Portugal. It is the second example of the group from the Lower Jurassic of Europe and it is the oldest known dinosaur from the Iberian Peninsula. It is based on a large left maxilla with teeth [1] that was lost in the fire at Museu Nacional de História Natural e da Ciência, Lisbon, in 1978. [2]
The fossil consists of a single partial left maxilla, an upper jaw bone, with seven teeth. The jaw measured 10.5 cm, with an estimated skull of 38.7 cm for the living animal. The teeth were described to be similar to those of Scelidosaurus , which approaches it narrowly by the presence of important anterior and posterior basilar points on each tooth. The maxilla was clearly bigger, being the double of the size than the maxilla of Scelidosaurus. Lapparent & Zbyszewski vinculated it originally with Scelidosaurus and assigned the two to Stegosauria, he described that the teeth present were different to Scelidosaurus. Ginsburg cited the specimen and note a bigger size than the holotype of Scelidosaurus. [3] Lusitanosaurus was probably a semibipedal to quadrupedal herbivore, with a dense armour on most parts of the body.
The genus was first described by Albert-Félix de Lapparent and Georges Zbyszewski in 1957. [4] The type species is Lusitanosaurus liasicus. The generic name is derived from Lusitania, the ancient Latin name for the region. The specific name refers to the Lias. The holotype was part of the collection of the Museu de História Natural da Universidade de Lisboa. The exact location of the find and the date of collection are unknown, which makes a correct geological dating difficult, but it can be inferred from the matrix rock that it has been discovered near São Pedro de Moel, in strata from the Late Sinemurian (Early Jurassic). [5] This would make it the oldest known dinosaur from Portugal.
It was originally assigned to the Stegosauria by de Lapparent, Lusitanosaurus was then considered a basal member of the Thyreophora, perhaps belonging to the Scelidosauridae, but this is tentative, as this family is considered paraphyletic. The fragmentary condition of the specimen does not help to identify it well, as it can be from different grades inside basal Thyreophora, such as a relative of Emausaurus . Some authors consider it a nomen dubium . [6] [7]
A revision of the phylogenetic relationships of early-diverging ornithischians found that the material of Lusitanosaurus as figured and described does not show any features characteristic of Thyreophora or even Ornithischia, and instead displays several differences that are found in the groups Pterosauria, Squamata, Tanystropheidae and basal Cynodontia. The presence of ankylothecodont teeth supported a placement of Lusitanosaurus preliminarily within Archosauromorpha, but not as an ornithischian. [8]
The São Pedro de Moel rocks consists on calcareous strata, mostly from Marginal Marine environments. [9] [10] Outside Lusitanosaurus, fishes have been found on this rock, such as members of the genus Proleptolepis . [11] Ammonites are also common, such as Oxynoticeras , Bifericeras , Cheltonia and Plesechioceras . [12] Finally, this section is known for its calcareous nannofossils that expose the Sinemurian/Pliensbachian transition more detailed than in any part of Portugal. [13]
Ornithischia is an extinct clade of mainly herbivorous dinosaurs characterized by a pelvic structure superficially similar to that of birds. The name Ornithischia, or "bird-hipped", reflects this similarity and is derived from the Greek stem ornith- (ὀρνιθ-), meaning "bird", and ischion (ἴσχιον), meaning "hip". However, birds are only distantly related to this group, as birds are theropod dinosaurs. Ornithischians with well known anatomical adaptations include the ceratopsians or "horn-faced" dinosaurs, the pachycephalosaurs or "thick-headed" dinosaurs, the armored dinosaurs (Thyreophora) such as stegosaurs and ankylosaurs, and the ornithopods. There is strong evidence that certain groups of ornithischians lived in herds, often segregated by age group, with juveniles forming their own flocks separate from adults. Some were at least partially covered in filamentous pelts, and there is much debate over whether these filaments found in specimens of Tianyulong, Psittacosaurus, and Kulindadromeus may have been primitive feathers.
Thyreophora is a group of armored ornithischian dinosaurs that lived from the Early Jurassic until the end of the Cretaceous.
Ankylosauria is a group of herbivorous dinosaurs of the clade Ornithischia. It includes the great majority of dinosaurs with armor in the form of bony osteoderms, similar to turtles. Ankylosaurs were bulky quadrupeds, with short, powerful limbs. They are known to have first appeared in the Middle Jurassic, and persisted until the end of the Cretaceous Period. The two main families of Ankylosaurs, Nodosauridae and Ankylosauridae are primarily known from the Northern Hemisphere, but the more basal Parankylosauria are known from southern Gondwana during the Cretaceous.
Kentrosaurus is a genus of stegosaurid dinosaur from the Late Jurassic in Lindi Region of Tanzania. The type species is K. aethiopicus, named and described by German palaeontologist Edwin Hennig in 1915. Often thought to be a "primitive" member of the Stegosauria, several recent cladistic analyses find it as more derived than many other stegosaurs, and a close relative of Stegosaurus from the North American Morrison Formation within the Stegosauridae.
Scelidosaurus is a genus of herbivorous armoured ornithischian dinosaur from the Jurassic of England.
Scutellosaurus is a genus of basal thyreophoran ornithischian dinosaur that lived approximately 196 million years ago during the early part of the Jurassic Period in what is now Arizona, USA. It is classified in Thyreophora, the armoured dinosaurs; its closest relatives may have been Emausaurus and Scelidosaurus, another armored dinosaur which was mainly a quadrupedal dinosaur, unlike bipedal Scutellosaurus. It is one of the earliest representatives of the armored dinosaurs and the basalmost form discovered to date. Scutellosaurus was a small, lightly-built, ground-dwelling herbivore, that could grow up to an estimated 1.3 metres (4.3 ft) long.
Alocodon is a genus of ornithischian dinosaur known from multiple teeth from the Middle or Late Jurassic Cabaços Formation of Portugal, and also the Forest Marble and Chipping Norton Formations of England. A single species is known, A. kuehnei.
Paranthodon is a genus of stegosaurian dinosaur that lived in what is now South Africa during the Early Cretaceous, between 139 and 131 million years ago. Discovered in 1845, it was one of the first stegosaurians found. Its only remains, a partial skull, isolated teeth, and fragments of vertebrae, were found in the Kirkwood Formation. British paleontologist Richard Owen initially identified the fragments as those of the pareiasaur Anthodon. After remaining untouched for years in the British Museum of Natural History, the partial skull was identified by South African paleontologist Robert Broom as belonging to a different genus; he named the specimen Palaeoscincus africanus. Several years later, Hungarian paleontologist Franz Nopcsa, unaware of Broom's new name, similarly concluded that it represented a new taxon, and named it Paranthodon owenii. Since Nopcsa's species name was assigned after Broom's, and Broom did not assign a new genus, both names are now synonyms of the current binomial, Paranthodon africanus. The genus name combines the Ancient Greek para (near) with the genus name Anthodon, to represent the initial referral of the remains.
Dracopelta is a monospecific genus of ankylosaur dinosaur from Portugal that lived during the Late Jurassic in what is now the Lourinhã Formation. The type and only species is Dracopelta zbyszewskii, which is represented by a partial skeleton including unpublished material.
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.
Tatisaurus is a genus of ornithischian dinosaur from the Early Jurassic from the Lower Lufeng Formation in Yunnan Province in China. Little is known as the remains are fragmentary. The type species is T. oehleri.
Dinheirosaurus is a genus of diplodocid sauropod dinosaur that is known from fossils uncovered in modern-day Portugal. It may represent a species of Supersaurus. The only species is Dinheirosaurus lourinhanensis, first described by José Bonaparte and Octávio Mateus in 1999 for vertebrae and some other material from the Lourinhã Formation. Although the precise age of the formation is not known, it can be dated around the early Tithonian of the Late Jurassic.
Lusotitan is a genus of herbivorous brachiosaurid sauropod dinosaur from the Late Jurassic of Portugal and possibly Spain.
Lourinhasaurus is an extinct genus of herbivorous sauropod dinosaur genus dating from Late Jurassic strata of Estremadura, Portugal.
Lourinhanosaurus was a genus of carnivorous theropod dinosaur that lived during the Late Jurassic Period (Kimmeridgian/Tithonian) in Portugal. It is one of many large predators discovered at the Lourinhã Formation and probably competed with coeval Torvosaurus gurneyi, Allosaurus europaeus, and Ceratosaurus.
The Lourinhã Formation is a fossil rich geological formation in western Portugal, named for the municipality of Lourinhã. The formation is mostly Late Jurassic in age (Kimmeridgian/Tithonian), with the top of the formation extending into the earliest Cretaceous (Berriasian). It is notable for containing a fauna especially similar to that of the Morrison Formation in the United States and a lesser extent to the Tendaguru Formation in Tanzania. There are also similarities to the nearby Villar del Arzobispo Formation and Alcobaça Formation. The stratigraphy of the formation and the basin in general is complex and controversial, with the constituent member beds belonging to the formation varying between different authors.
Laquintasaura is a genus of Venezuelan ornithischian dinosaur containing only the type species Laquintasaura venezuelae. The species was the first dinosaur to have been identified from Venezuela. It is known from extensive remains, all from a single bonebed locality which has been sampled for specimen blocks over the course of several expeditions, largely led by Marcelo R Sánchez-Villagra. A small animal, it is known for its distinct dental anatomy and for being one of the earliest and most primitive ornithischians in the fossil record. Taxonomic uncertainty has led to conflicting hypotheses that it is either at the base of Ornithischia or at the base of the subgroup Thyreophora. In either model, its dating to around 200 million years ago at the start of the Jurassic, existence in equatorial latitudes, and primitive nature make it a key insight into early ornithischian evolution. It is thought that Laquintasaura would have lived in groups and had a possible omnivorous diet, living on a seasonal alluvial plain and being preyed upon by the contemporary Tachiraptor.
Susannah "Susie" Catherine Rose Maidment is a British palaeontologist at the Natural History Museum, London. She is also an honorary Professor at the University of Birmingham. She is internationally recognised for her research on ornithischian dinosaur evolution, and was awarded the 2016 Hodson Award of the Palaeontological Association and the 2017 Lyell Fund of the Geological Society of London. She was featured as a 2019 National Geographic Women of Impact.
Plesiopharos is an extinct genus of plesiosaur from the Early Jurassic Coimbra Formation of Portugal. Specifically, it was discovered in São Pedro de Moel, Marinha Grande, from which the type species' binomial name, Plesiopharos moelensis, derives from.
Jakapil is a genus of basal thyreophoran dinosaur from the Candeleros Formation of Argentina. The type species is Jakapil kaniukura.