Abditosaurus Temporal range: Late Cretaceous, (Maastrichtian) | |
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Life reconstruction of Abditosaurus kuehnei | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | Saurischia |
Clade: | † Sauropodomorpha |
Clade: | † Sauropoda |
Clade: | † Macronaria |
Clade: | † Titanosauria |
Clade: | † Lithostrotia |
Family: | † Saltasauridae |
Subfamily: | † Saltasaurinae |
Genus: | † Abditosaurus Vila et al., 2022 |
Species: | †A. kuehnei |
Binomial name | |
†Abditosaurus kuehnei Vila et al., 2022 | |
Abditosaurus (meaning "forgotten lizard") is an extinct genus of titanosaurian sauropod dinosaur from the Late Cretaceous (Maastrichtian) Tremp Group of Catalonia, Spain. The type and only species is Abditosaurus kuehnei. Phylogenetic analyses recover it within a clade of South American and African saltasaurines, distinct from other insular dwarf sauropods from the European archipelago. Abditosaurus inhabited the Ibero-Armorican Island, a prehistoric island made up of what is now Spain, Portugal, and southern France, and would have been the largest titanosaur species in its environment. [1]
While prospecting for fossil mammals in 1954, German paleontologist Walter Georg Kühne on 25 September discovered the remains of a large titanosaur at the Orcau-1 locality of the Conques Formation of Catalonia, Spain. It was the first major sauropod find in Spain. During the initial two weeks of excavation Kühne managed to identify around ten bones, some of which were packaged and sent to the Instituto Lucas Mallada (ILM) in Madrid, while others remained at the site (jacketed for protection). Returning the following year, Kühne, alongside locals and researchers of the ILM, managed to identify ten more bones in addition to most of those left at the site. Like in 1954, some of the bones were transported to Madrid while the remainder were left at the site. These initial discoveries consisted of fragments of the ilium, parts of the scapula, dorsal vertebrae, chevrons, a tibia, parts of the femurs and a complete humerus alongside undetermined bones. Although Kühne asked for additional excavations, funding had run out and work at the locality was stopped. In 1956, the fossil material recovered was assigned by Albert-Félix de Lapparent and Emiliano Aguirre to a new, but unnamed, species of the now dubious genus Hypselosaurus . [2] It was not until 1984 and 1986 that additional expeditions to the area were conducted, helmed by Josep Vicenç Santafé of the Institut de Paleontologia de Sabadell, Barcelona, and assisted by researchers of the Institut d’Estudis Ilerdencs, Lleida. They identified a sternal plate and additional dorsal vertebrae. Another expedition was conducted from 2012 to 2014 by the Institut Català de Paleontologia, the University of Zaragoza and the Museu de la Conca Dellà. This expedition recovered elements left at the site by the 1955 and 1986 digs, with additional material of the limbs, tooth fragments, ribs and an articulated series of dorsal and cervical vertebrae. Subsequent research managed to discover some of the historical material. [1] In 2017, part of the initial finds were described. [3] This finding was shown in the 2017 documentary "Europe's Last Giant".
The type specimen, which has numerous accession numbers, is the most complete known European titanosaur skeleton, with the semi-articulated neck, preserving twelve of the estimated fourteen cervical vertebrae, being especially noteworthy. [4] Complete and nearly complete sequences of neck vertebrae are very rare in sauropods; as of early 2022, only 27 sauropod specimens with complete or nearly complete necks were known. [5] It was the first semi-articulated titanosaur specimen discovered in Europe. [6]
In 2022, the type species Abditosaurus kuehnei was named and described by Bernat Vila, Albert Sellés, Miguel Moreno-Azanza, Novella L. Razzolini, Alejandro Gil-Delgado, José Ignacio Canudo and Àngel Galobart. The generic name, Abditosaurus, means "forgotten reptile", [7] and is derived from the Latin abditus, meaning "concealed," or "forgotten," as the fossil material was hidden for sixty years between the initial discovery and the last expedition that collected the last bones, and the Greek sauros, meaning "lizard". The specific name, kuehnei, honors Walter Georg Kühne, the discoverer of the type specimen. [1]
Abditosaurus is noted for its large size, and is the largest titanosaur from the Ibero-Armorican Island, a geological region composing most of Spain and Southern France. [7] [4] It is estimated to have reached a length of 17.5 metres (57 ft) and mass of 14 tonnes (15 short tons). [1]
The holotype includes an ossified sternal rib and an ossified calcaneum, elements which hitherto had not been unequivocally identified in titanosaur specimens, leading to speculation that they had fully disappeared in the group. These bones probably ossified due to the advanced individual age of the holotype, which was also proven by its bone structure. [1]
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Phylogenetic position of Abditosaurus within Saltasauridae according to Vila et al. 2022. [1] European genera are highlighted in pink, showing that Abditosaurus is not closely related to other European titanosaurs. |
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Phylogenetic position of Abditosaurus within Eutitanosauria, after a 2023 analysis by Gorscak and colleagues, showing the results of their tip-dated Bayesian analysis [8] |
The discoverers of Abditosaurus interpreted it as a member of Saltasaurinae, a clade of titanosaurs found in South America and Africa. Their phylogenetic analysis recovered the Egyptian sauropod Paralititan as the sister taxon of Abditosaurus, with the Brazilian Maxakalisaurus as their next-closest relative. The clade uniting these three species, in turn, formed a sister clade to Saltasaurini. As such, Abditosaurus is not closely related to other European sauropods, the majority of which were recovered as opisthocoelicaudiines by their phylogenetic analysis. [1] A subsequent study, using a revised version of the dataset used by Vila and colleagues, found Abditosaurus to occupy a different position, forming a clade with Alamosaurus , Pellegrinisaurus , Baurutitan , and Dreadnoughtus that was closely related to lognkosaurs. [8]
The only known specimen of Abditosaurus was found in the Conques Formation, which dates to the early Maastrichtian age of the Cretaceous. At this time, southern France, Spain, and Portugal formed an island, known as the Ibero-Armorican Island. Most titanosaur taxa of the Ibero-Armorican Island, such as Lirainosaurus , Atsinganosaurus , Garrigatitan , Ampelosaurus , and Lohuecotitan , were small or medium-sized. In contrast, Abditosaurus was significantly larger and lacked physiological adaptations to an island environment, suggesting that the species was a recent arrival in the ecosystem. It may be part of a broader trend of larger sauropods replacing smaller endemic species in Europe during the early Maastrichtian, as larger sauropods first appear in the Hațeg biota around the same time. Abditosaurus is associated with eggs of the oospecies Fusioolithus baghensis , which closely resemble eggs found in Gondwana. [1]
Titanosaurs were a diverse group of sauropod dinosaurs, including genera from all seven continents. The titanosaurs were the last surviving group of long-necked sauropods, with taxa still thriving at the time of the extinction event at the end of the Cretaceous. This group includes some of the largest land animals known to have ever existed, such as Patagotitan—estimated at 37 m (121 ft) long with a weight of 69 tonnes —and the comparably-sized Argentinosaurus and Puertasaurus from the same region.
Alamosaurus is a genus of opisthocoelicaudiine titanosaurian sauropod dinosaurs containing a single known species, Alamosaurus sanjuanensis, from the Maastrichtian age of the Late Cretaceous period in what is now southwestern North America. Isolated vertebrae and limb bones indicate that it reached sizes comparable to Argentinosaurus and Puertasaurus, which would make it the absolute largest dinosaur known from North America. Its fossils have been recovered from a variety of rock formations spanning the Maastrichtian age. Specimens of a juvenile Alamosaurus sanjuanensis have been recovered from only a few meters below the Cretaceous-Paleogene boundary in Texas, making it among the last surviving non-avian dinosaur species. Alamosaurus is the only known sauropod to have inhabited North America after their nearly 30-million year absence from the North American fossil record and probably represents an immigrant from South America.
Aeolosaurus is a genus of titanosaurian sauropod dinosaur from the Late Cretaceous Period of what is now South America. Like most sauropods, it would have been a quadrupedal herbivore with a long neck and tail. Aeolosaurus is well known for a titanosaur, as it is represented by the remains of several individuals belonging to at least two species. However, like most titanosaurs, no remains of the skull are known. The holotype of Aeolosaurus rionegrinus consists of a series of seven tail vertebrae, as well as parts of both forelimbs and the right hindlimb. It was discovered in the Angostura Colorada Formation in Argentina, which dates from the Campanian stage of the Late Cretaceous, about 83 to 74 million years ago. The species A. maximus was transferred over to the new genus Arrudatitan in 2021.
Aralosaurus was a genus of hadrosaurid dinosaur that lived during the Late Cretaceous in what is now Kazakhstan. It is known only by a posterior half of a skull and some post-cranial bones found in the Bostobe Formation in rocks dated from the Upper Santonian-Lower Campanian boundary, at about 83.6 Ma. Only one species is known, Aralosaurus tuberiferus, described by Anatoly Konstantinovich Rozhdestvensky in 1968. The genus name means Aral Sea lizard, because it was found to the northeast of the Aral Sea. The specific epithet tuberiferus means bearing a tuber because the posterior part of the nasal bone rises sharply in front of the orbits like an outgrowth. Aralosaurus was originally reconstituted with a nasal arch similar to that of North American Kritosaurus. For many years, Aralosaurus was thus placed in the clade of the Hadrosaurinae. This classification was invalidated in 2004, following the re-examination of the skull of the animal which allowed to identify in Aralosaurus many typical characters of Lambeosaurinae. In particular, this study revealed that Aralosaurus had a hollow bony structure located far in front of the orbits, which communicated with the respiratory tract. This structure being broken at its base, its shape and size remains undetermined. More recently, Aralosaurus has been identified as the most basal Lambeosaurinae, and placed with its close relative Canardia from the upper Maastrichtian of France in the new clade of Aralosaurini.
Ampelosaurus is a titanosaurian sauropod dinosaur from the Late Cretaceous Period of what is now France. Its type species is A. atacis, named by Le Loeuff in 1995. Its remains were found in a level dating from 71.5 million years ago representing the early Maastrichtian.
Adamantisaurus is a poorly-known genus of titanosaurian sauropod dinosaur from the Late Cretaceous Period of what is now South America. It is only known from six tail vertebrae but, as a sauropod, it can be assumed that this dinosaur was a very large animal with a long neck and tail.
Pararhabdodon is a genus of tsintaosaurin hadrosaurid dinosaur, from the Maastrichtian-age Upper Cretaceous Tremp Group of Spain. The first remains were discovered from the Sant Romà d’Abella fossil locality and assigned to the genus Rhabdodon, and later named as the distinct species Pararhabdodon isonensis in 1993. Known material includes assorted postcranial remains, mostly vertebrae, as well as maxillae from the skull. Specimens from other sites, including remains from France, a maxilla previously considered the distinct taxon Koutalisaurus kohlerorum, an additional maxilla from another locality, the material assigned to the genera Blasisaurus and Arenysaurus, and the extensive Basturs Poble bonebed have been considered at different times to belong to the species, but all of these assignments have more recently been questioned. It was one of the last non-avian dinosaurs known from the fossil record that went extinct during the Cretaceous-Paleogene extinction event.
Epachthosaurus was a genus of titanosaurian sauropod dinosaur from the Late Cretaceous. It was a basal lithostrotian titanosaur. Its fossils have been found in Central and Northern Patagonia in South America.
Lirainosaurus is a genus of titanosaur sauropod which lived in what is now Spain. The type species, Lirainosaurus astibiae, was described by Sanz, Powell, Le Loeuff, Martinez, and Pereda-Suberbiola in 1999. It was a relatively small sauropod, measuring 4 metres (13 ft) long, possibly up to 6 metres (20 ft) long for the largest individuals, and weighed about 2–4 metric tons.
Gargantuavis is an extinct genus of large, primitive bird containing the single species Gargantuavis philoinos. It is the only member of the monotypic family Gargantuaviidae. Its fossils were discovered in several formations dating to 73.5 and 71.5 million years ago in what is now northern Spain, southern France, and Romania. Gargantuavis is the largest known bird of the Mesozoic, a size ranging between the cassowary and the ostrich, and a mass of 141 kg (311 lb) like modern ostriches, exemplifying the extinction of non-avian dinosaurs was not a necessary condition for the emergence of giant terrestrial birds. It was once thought to be closely related to modern birds, but the 2019 discovery of a pelvis from what was Hateg Island shows several primitive features.
Atsinganosaurus is a genus of titanosaurian sauropod dinosaur which existed in what is now France during the Late Cretaceous. Well-preserved remains of Atsinganosaurus were collected from the Grès à Reptiles Formation of the Aix-en-Provence Basin. The type and only species is A. velauciensis.
Saltasaurinae is a subfamily of titanosaurian sauropods known from the late Cretaceous period of South America, India and Madagascar.
Canardia is an extinct genus of lambeosaurine dinosaur known from the Late Cretaceous Marnes d'Auzas Formation of Haute-Garonne department, in Occitanie region, southwestern France. The type species Canardia garonnensis was first described and named by Albert Prieto-Márquez, Fabio M. Dalla Vecchia, Rodrigo Gaete and Àngel Galobart in 2013. It is only known from juvenile specimens. The name of the genus comes from “canard”, the French word for “duck”, an allusion to the fact that this animal belongs to the hadrosaurids which are also known as duck-billed dinosaurs. The specific epithet garonnensis refers to the Haute-Garonne department where this dinosaur has been found. Although universally recognized as a lambeosaurine, its precise position within them is debated. Some authors consider it as a close relative of the genus Aralosaurus from Central Asia with which it would form the tribe Aralosaurini, while others include it in a more derived clade, the Arenysaurini in which all lambeosaurines from Europe and North Africa are placed. Canardia was one of the last non-avian dinosaurs and lived between 67,5 and 66 my on the former Ibero-Armorican Island, which included much of France and Spain.
Sarmientosaurus is a genus of titanosaurian sauropod dinosaur belonging to the Titanosauria. It lived in what is now South America, specifically Argentina, during the Upper Cretaceous Period about 95 million years ago. The type species is Sarmientosaurus musacchioi.
Lohuecotitan is an extinct genus of titanosaurian sauropod dinosaur which lived during the Late Cretaceous in Spain. The only species known in the genus is Lohuecotitan pandafilandi, described and named in 2016.
Austroposeidon is a genus of titanosaurian sauropod dinosaur from the Late Cretaceous Presidente Prudente Formation of Brazil. It contains one species, Austroposeidon magnificus.
Sibirotitan is a genus of somphospondyl sauropod from the Ilek Formation of Russia. The type and only species is S. astrosacralis.
Adynomosaurus is a genus of lambeosaurine dinosaur from the Late Cretaceous of what is now Catalonia, Spain. First discovered in 2012, it was named in 2019 with the type and only species being Adynomosaurus arcanus. It is only known from scant material, but is distinguished from other hadrosaurs by its weakly developed shoulder blade which would have had underdeveloped musculature, which lends it its scientific name, partially from the Greek word for "weak". Its exact relationships with other hadrosaurs remain unresolved, with it not consistently being recovered as a relative of any other specific genera, though some studies have allied it with Tsintaosaurini or even found it outside of Hadrosauridae. It would have lived as part of a diverse coastal estuary ecosystem, made up of meandering rivers and mud flats. The discovery of Adynomosaurus adds to the very incomplete fossil record of hadrosaurid dinosaurs in the Late Cretaceous of Europe, and it fits into a picture of major ecological turnover that was occurring during the Maastrichtian stage in the region.
Saltasaurini is a tribe of titanosaur sauropods known from the Late Cretaceous of Patagonia, Argentina. The clade was named in 2007 by Leonardo Salgado and José Bonaparte for the "least inclusive clade comprising Neuquensaurus and Saltasaurus", being equivalent to the use of Saltasaurinae in Salgado et al. (1997). Found only in the Campanian to Maastrichtian sediments of the Neuquén Basin, Salgado & Bonaparte (2007) decided a more restrictive clade was needed because of the expansion of Saltasaurinae as defined to include far more taxa than it originally encompassed. Saltasaurini includes the original core of Saltasaurinae: Neuquensaurus, Saltasaurus, Rocasaurus and Bonatitan, although some studies exclude Bonatitan from the clade.
Tamarro is a genus of troodontid theropod from the Late Cretaceous Talarn Formation of Spain. The genus contains a single species, Tamarro insperatus, known from a partial metatarsal described in 2021.