Elaltitan

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Elaltitan
Temporal range: Cenomanian-Turonian
~96.5–89.3  Ma
Elaltitan lilloi Skeletal Mk II Gunnar Bivens.jpg
Skeletal restoration, known material in blue
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Sauropodomorpha
Clade: Sauropoda
Clade: Macronaria
Clade: Titanosauria
Clade: Lithostrotia
Genus: Elaltitan
Mannion & Otero, 2012
Type species
Elaltitan lilloi
Mannion & Otero, 2012

Elaltitan is an extinct genus of large lithostrotian titanosaur sauropod dinosaur known from the Late Cretaceous (mid Cenomanian to Turonian stage) of Chubut Province, southern Argentina. It contains a single species, Elaltitan lilloi. [1]

Etymology

Elaltitan was first described and named by Philip D. Mannion and Alejandro Otero in 2012 and the type species is Elaltitan lilloi. The generic name is derived from Elal (pronounced as "ee-lal") - the god of the Tehuelche people of Chubut Province and titan , giant in Greek mythology. The specific name, lilloi, honors Miguel Lillo, for his contribution and legacy to natural sciences in Tucumán. [1]

Discovery

Elaltitan is known only from a single individual, represented by an associated partial postcranial skeleton. The holotype includes both PVL 4628 and MACN-CH 217 comprising three dorsal vertebrae, two caudal vertebrae, left scapula, left humerus, left radius, both ulnae, right pubis, proximal half of right femur, distal part of left tibia, distal two-thirds of left fibula, right astragalus and calcaneum. Elaltitan is the first titanosaur skeleton to preserve an associated calcaneum. Although all of the material was originally housed in the Colección de Paleontología de Vertebrados de la Fundación Instituto Miguel Lillo in Tucumán, Argentina and accessioned as PVL 4628, the dorsal vertebrae and complete caudal vertebra were subsequently moved to the Museo Argentino de Ciencias Naturales “Bernardino Rivadavia” in Buenos Aires, where they were accessioned as MACN-CH 217. The holotype specimen was collected by an expedition of the Fundación Miguel Lillo and the Universidad Nacional de Tucumán, led by José Fernando Bonaparte, from the right (southern) bank of the Senguerr River, in the area between the bend of this river and the Pampa de María Santísima, southeast of the southernmost part of the Sierra de San Bernardo, Chubut Province. It came from the lower member of the Bajo Barreal Formation, dating to the middle Cenomanian to the Turonian stage of the Late Cretaceous period, about 96.5-89.3  million years ago. [1]

Description

The holotype of Elaltitan was originally attributed to Antarctosaurus sp. by Bonaparte & Gasparini (1979), and later tentatively referred to Argyrosaurus by Jaime Powell (1986, 2003). Philip D. Mannion and Alejandro Otero (2012), who named the genus, diagnosed Elaltitan by a unique combination of characters, as well as one autapomorphy. The autapomorphy (unique trait) is the presence of dorsoventrally tall neural arch restricted to anterior half of centrum (excluding condylar ball) in anterior-most caudal vertebrae. Other unusual characters include a spinopostzygapophyseal laminae in middle–posterior dorsal vertebrae bifurcate into medial and lateral branches, an astragalar ascending process that does not extend to the posterior margin of the astragalus and the presence of a calcaneum. Other potentially unusual features were also listed. These traits distinguish Elaltitan from all other titanosauriforms, including Antarctosaurus and Argyrosaurus , as well as other sauropods from the lower member of the Bajo Barreal Formation, such as Drusilasaura and Epachthosaurus . Based on comparisons with the morphologically similar femur of "Antarctosaurus " giganteus, which was measured as 231 cm (91 in) in length, the complete femur of Elaltitan would be approximately the same size. This makes it one of the largest known sauropods ever to have existed. Mannion & Otero (2012) also pointed out that there are currently 39 Cretaceous South American titanosauriform genera considered to be valid, the majority of which (31) are from Argentina. [1] Its weight has been estimated at 42.8 tonnes (42.1 long tons; 47.2 short tons) in 2014, [2] and at 35.4 tonnes (34.8 long tons; 39.0 short tons) in 2018. [3] However, in 2020 Molina-Perez and Larramendi gave a smaller size of 20 meters (66 ft) and 23 tonnes (25.35 short tons). [4]

Related Research Articles

<i>Argentinosaurus</i> Late Cretaceous giant sauropod dinosaur genus

Argentinosaurus is a genus of giant sauropod dinosaur that lived during the Late Cretaceous period in what is now Argentina. Although it is only known from fragmentary remains, Argentinosaurus is one of the largest known land animals of all time, perhaps the largest, measuring 30–35 metres (98–115 ft) long and weighing 65–80 tonnes. It was a member of Titanosauria, the dominant group of sauropods during the Cretaceous. It is widely regarded by many paleontologists as the biggest dinosaur ever, and perhaps lengthwise the longest animal ever, though both claims have no concrete evidence yet.

<span class="mw-page-title-main">Titanosauria</span> Extinct clade of dinosaurs

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.

<i>Antarctosaurus</i> Sauropod dinosaur genus from Late Cretaceous

Antarctosaurus is a genus of titanosaurian sauropod dinosaur from the Late Cretaceous Period of what is now South America. The type species, Antarctosaurus wichmannianus, and a second species, Antarctosaurus giganteus, were described by prolific German paleontologist Friedrich von Huene in 1929. Three additional species of Antarctosaurus have been named since then but later studies have considered them dubious or unlikely to pertain to the genus.

<i>Argyrosaurus</i> Genus of herbivorous titanosaurian sauropod dinosaur

Argyrosaurus is a genus of titanosaurian sauropod dinosaur that lived about 70 million years ago, during the Late Cretaceous Period of what is now Argentina.

<i>Aeolosaurus</i> Extinct genus of dinosaurs

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.

<i>Euhelopus</i> Extinct genus of dinosaurs

Euhelopus is a genus of sauropod dinosaur that lived between 145 and 133 million years ago during the Berriasian and Valanginian stages of the Early Cretaceous in what is now Shandong Province in China. It was a large quadrupedal herbivore. Like sauropods such as brachiosaurs and titanosaurs, Euhelopus had longer forelegs than hind legs. This discovery was paleontologically significant because it represented the first dinosaur scientifically investigated from China: seen in 1913, rediscovered in 1922, and excavated in 1923 and studied by T'an during the same year. Unlike most sauropod specimens, it has a relatively complete skull.

<i>Epachthosaurus</i> Extinct genus of dinosaurs

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.

Gobititan is a genus of herbivorous sauropod dinosaur from the Aptian faunal stage of the Early Cretaceous. The name of this genus is derived from the Gobi desert region and the Titans of Greek mythology, which is a reference to its large body size. The specific name shenzhouensis, is derived from "Shenzhou", an ancient name for China.

<i>Neuquensaurus</i> Extinct genus of dinosaurs

Neuquensaurus is a genus of saltasaurid sauropod dinosaur that lived in the Late Cretaceous, about 80 million years ago in Argentina in South America. Its fossils were recovered from outcrops of the Anacleto Formation around Cinco Saltos, near the Neuquén river from which its name is derived.

<i>Pellegrinisaurus</i> Extinct genus of dinosaurs

Pellegrinisaurus is a genus of titanosaurian sauropod dinosaur that lived in South America during the Late Cretaceous period. The holotype was found in the Allen Formation, Argentina.

Amargatitanis is a genus of dicraeosaurid sauropod dinosaur from the Barremian-age La Amarga Formation of Neuquén, Argentina. It is known from a single, incomplete postcranial skeleton consisting of a partial hindlimb, ischium, and two vertebrae. These remains were unearthed by Argentine paleontologist José Bonaparte in 1983 during an expedition by the Museo Argentino de Ciencias Naturales and later described as a new genus and species, Amargatitanis macni by Sebastián Apesteguía. The genus name comes from the words Amarga, where the fossils were collected, and titanis meaning "titan". Its species name is in reference to the MACN, where the remains are stored.

<i>Ruyangosaurus</i> Extinct genus of dinosaurs

Ruyangosaurus is a genus of titanosauriform sauropod dinosaur recovered from the Early Cretaceous Haoling Formation of China. The type species is R. giganteus, described in 2009 by Lü Junchang et al.

<i>Xianshanosaurus</i> Extinct genus of dinosaurs

Xianshanosaurus is a genus of sauropod dinosaur from the Early Cretaceous (Aptian-Albian) of the Ruyang Basin in Henan Province, China. Its type and only species is Xianshanosaurus shijiagouensis. It was described in 2009 by a team of paleontologists led by Lü Junchang. Xianshanosaurus may be a titanosaur, and Daxiatitan may be its closest relative, but its evolutionary relationships remain controversial.

<i>Katepensaurus</i> Extinct genus of rebbachisaurid dinosaurs

Katepensaurus is an extinct genus of rebbachisaurid sauropod dinosaur known from the Late Cretaceous of south-central Chubut Province of central Patagonia, Argentina. It contains a single species, Katepensaurus goicoecheai.

<i>Patagotitan</i> Extinct genus of dinosaurs

Patagotitan is a genus of titanosaurian sauropod dinosaur from the Cerro Barcino Formation in Chubut Province, Patagonia, Argentina. The genus contains a single species known from at least six young adult individuals, Patagotitan mayorum, which was first announced in 2014 and then named in 2017 by José Carballido and colleagues. Preliminary studies and press releases suggested that Patagotitan was the largest known titanosaur and land animal overall, with an estimated length of 37 m (121 ft) and an estimated weight of 69 tonnes. Later research revised the length estimate down to 31 m (102 ft) and weight estimates down to approximately 50–57 tonnes, suggesting that Patagotitan was of a similar size to, if not smaller than, its closest relatives Argentinosaurus and Puertasaurus. Still, Patagotitan is one of the most-known titanosaurs, and so its interrelationships with other titanosaurs have been relatively consistent in phylogenetic analyses. This led to its use in a re-definition of the group Colossosauria by Carballido and colleagues in 2022.

<i>Notocolossus</i> Extinct genus of dinosaurs

Notocolossus is a genus of titanosaurian sauropod dinosaur from late Cretaceous strata of Mendoza Province, Argentina.

<i>Savannasaurus</i> Extinct genus of dinosaurs

Savannasaurus is a genus of titanosaurian sauropod dinosaur from the Late Cretaceous Winton Formation of Queensland, Australia. It contains one species, Savannasaurus elliottorum, named in 2016 by Stephen Poropat and colleagues. The holotype and only known specimen, originally nicknamed "Wade", is the most complete specimen of an Australian sauropod, and is held at the Australian Age of Dinosaurs museum. Dinosaurs known from contemporary rocks include its close relative Diamantinasaurus and the theropod Australovenator; associated teeth suggest that Australovenator may have fed on the holotype specimen.

The Lago Colhué Huapí Formation is a Late Cretaceous geologic formation of the Chubut Group in the Golfo San Jorge Basin in Patagonia, Argentina. The formation, named after Lake Colhué Huapí, is overlain by the Salamanca Formation of the Río Chico Group and in some areas by the Laguna Palacios Formation.

Ruixinia is an extinct genus of somphospondylan titanosauriform dinosaur from the Early Cretaceous (Barremian) Yixian Formation of China. The genus contains a single species, Ruixinia zhangi. The Ruixinia holotype is a partial articulated skeleton with the most complete series of caudal vertebrae known from any Asian titanosauriform.

<i>Garumbatitan</i> Genus of somphospondylan sauropod dinosaurs

Garumbatitan is an extinct genus of somphospondylan sauropod dinosaur from the Cretaceous Arcillas de Morella Formation of Spain. The genus contains a single species, G. morellensis, known from multiple partial skeletons.

References

  1. 1 2 3 4 Mannion, P. D.; Otero, A. (2012). "A reappraisal of the Late Cretaceous Argentinean sauropod dinosaur Argyrosaurus superbus, with a description of a new titanosaur genus". Journal of Vertebrate Paleontology. 32 (3): 614–638. Bibcode:2012JVPal..32..614M. doi:10.1080/02724634.2012.660898. hdl: 11336/197194 . S2CID   86762374.
  2. Benson, R. B. J.; Campione, N. S. E.; Carrano, M. T.; Mannion, P. D.; Sullivan, C.; Upchurch, P.; Evans, D. C. (2014). "Rates of Dinosaur Body Mass Evolution Indicate 170 Million Years of Sustained Ecological Innovation on the Avian Stem Lineage". PLOS Biology. 12 (5): e1001853. doi: 10.1371/journal.pbio.1001853 . PMC   4011683 . PMID   24802911.
  3. Benson, R. B. J.; Hunt, G.; Carrano, M.T.; Campione, N.; Mannion, P. (2018). "Cope's rule and the adaptive landscape of dinosaur body size evolution". Palaeontology. 61 (1): 13–48. Bibcode:2018Palgy..61...13B. doi: 10.1111/pala.12329 .
  4. Molina-Perez & Larramendi (2020). Dinosaur Facts and Figures: The Sauropods and Other Sauropodomorphs. New Jersey: Princeton University Press. p. 266. Bibcode:2020dffs.book.....M.