Kotasaurus (/ˌkoʊtəˈsɔːrəs/ KOH-tə-SAWR-əs; meaning "Kota Formation lizard") is a genus of sauropod dinosaur from the Early Jurassic period (Sinemurian–Pliensbachian). The only known species is Kotasaurus yamanpalliensis. It was discovered in the Kota Formation of Telangana, India and shared its habitat with the related Barapasaurus. So far the remains of at least 12 individuals are known. The greater part of the skeleton is known, but the skull is missing, with the exception of two teeth. Like all sauropods, it was a large, quadrupedal herbivore with long neck and tail.
|Mounted skeleton of Kotasaurus|
Kotasaurus is one of the most basal sauropods known. The general body plan was that of a typical sauropod, but in several basal (plesiomorphic) features it resembles prosauropods. Like all sauropods, Kotasaurus was an obligate quadruped, while prosauropods were primitively bipedal. The body length is estimated at roughly nine meters, with a weight of 2.5 tonnes, and therefore already comparable with that of later sauropods. The femur was straight and oval in cross section, which means that the limbs were already columnar. The teeth were spoon-shaped, like those of later sauropods. Basal features, on the other hand, include the relatively short and slightly twisted humerus, as well as the retention of a lesser trochanter on the femur. The neural spines of the vertebrae were simply built and their centra are massive, in contrast to those of the related Barapasaurus, which show more hollowing, be it without pneumatisation, of the sides as a weight-saving measure.
Initially, it was not clear if Kotasaurus represents a true sauropod or a basal sauropodomorph that has to be classified outside Sauropoda. Some paleontologists placed it inside a basal sauropod family called Vulcanodontidae though, together with Barapasaurus and the fragmentary Ohmdenosaurus and Zizhongosaurus. This grouping is now recognized to be paraphyletic.
Today Kotasaurus is recognized as one of the most basal sauropods known. The exact relationships are not entirely clear, however. A recent study by Bandyopadhyay and colleagues (2011) renders Kotasaurus to be more basal than Barapasaurus and Vulcanodon but more derived than Jingshanosaurus, Antetonitrus and Chinshakiangosaurus.
All known fossils come from an area of 2,400 m² near the village of Yamanpalli in Telangana, approximately forty kilometres north of the Barapasaurus type locality. These finds, altogether 840 skeletal parts, were found in the late 1970s. In 1988 they were named and described by P.M. Yadagiri as a new genus and species of sauropod, Kotasaurus yamanpalliensis. The generic name refers to the Kota Formation. The specific name reflects the provenance from Yamanpalli. The holotype is 21/SR/PAL, an ilium.
Apatosaurinae is the name of a subfamily of diplodocid sauropods that existed between 157 and 150 million years ago in North America. The group includes two genera for certain, Apatosaurus and Brontosaurus, with at least five species. Atlantosaurus and Amphicoelias might also belong to this group.Below is a cladogram of apatosaurinae interrelationships based on Tschopp et al., 2015.Argyrosauridae
Argyrosauridae is a family of large titanosaurian dinosaurs known from the late Cretaceous period of Argentina and Egypt. The group has been recovered as monophyletic, including the type genus Argyrosaurus as well as Paralititan.Barapasaurus
Barapasaurus ( bə-RAH-pə-SAWR-əs) is a genus of basal sauropod dinosaur from Early Jurassic rocks of India. The only species is B. tagorei. Barapasaurus comes from the lower part of the Kota Formation, that dates back to the Sinemurian and Pliensbachian stages of the early Jurassic. It is therefore one of the earliest known sauropods. Barapasaurus is known from approximately 300 bones from at least six individuals, so that the skeleton is almost completely known except for the anterior cervical vertebrae and the skull. This makes Barapasaurus one of the most completely known sauropods from the early Jurassic.Birla Science Museum
B. M. Birla Science Museum is an Indian science museum located in Hyderabad, India. Constructed by civil engineer P. A. Singaravelu, it comprises a planetarium, museum, science centre, art gallery as well as a dinosaurium. The museum itself was the second phase of the science centre when it opened in 1990.Brasilotitan
Brasilotitan is a genus of titanosaurian sauropod dinosaur from the Late Cretaceous (early Maastrichtian) Adamantina Formation of Brazil. The type species is Brasilotitan nemophagus.Cetiosauridae
Cetiosauridae is a family of sauropod dinosaurs. While traditionally a wastebasket taxon containing various unrelated species, some recent studies have found that it may represent a natural clade. Additionally, at least one study has suggested that the mamenchisaurids may represent a sub-group of the cetiosaurids, which would be termed Mamenchisaurinae.Chinshakiangosaurus
Chinshakiangosaurus (JIN-shah-jiahng-uh-SOR-us, meaning "Chinshakiang lizard") is a genus of dinosaur and probably one of the most basal sauropods known. The only species, Chinshakiangosaurus chunghoensis, is known from a fragmentary skeleton found in Lower Jurassic rocks in China. Chinshakiangosaurus is one of the few basal sauropods with preserved skull bones and therefore important for the understanding of the early evolution of this group. It shows that early sauropods may have possessed fleshy cheeks.Diplodocinae
Diplodocinae is an extinct subfamily of diplodocid sauropods that existed from the Late Jurassic to Early Cretaceous of North America, Europe and South America, about 161.2 to 136.4 million years ago. Genera within the subfamily include Tornieria, Supersaurus, Leinkupal, Galeamopus, Diplodocus, Kaatedocus and Barosaurus.Cladogram of the Diplodocidae after Tschopp, Mateus, and Benson (2015).Eomamenchisaurus
Eomamenchisaurus (meaning "dawn Mamenchisaurus") is a genus of mamenchisaurid sauropod dinosaur from the Middle Jurassic of Yuanmou, Yunnan, China. The type species is E. yuanmouensis, described by Lü Junchang et al. in 2008.Ferganasaurus
Ferganasaurus was a genus of dinosaur first formally described in 2003 by Alifanov and Averianov. The type species is Ferganasaurus verzilini. It was a sauropod similar to Rhoetosaurus. The fossils were discovered in 1966 in Kyrgyzstan from the Balabansai Formation and date to the Callovian stage of the Middle Jurassic.Flagellicaudata
Flagellicaudata is a clade of Dinosauria. It belongs to Sauropoda and includes two families, the Dicraeosauridae and the Diplodocidae.Gravisauria
Gravisauria is a clade of sauropod dinosaurs consisting of some genera, Vulcanodontidae and Eusauropoda.Jiutaisaurus
Jiutaisaurus is a genus of sauropod dinosaur from the Quantou Formation of China. Jiutaisaurus was a sauropod which lived during the Cretaceous. The type species, Jiutaisaurus xidiensis, was described by Wu et al. in 2006, and is based on eighteen vertebrae.Microcoelus
Microcoelus is a dubius genus of small Titanosaurian sauropod dinosaur native to Argentina. It is known from only a single dorsal vertebra. A left humerus was formerly referred to this species, but it is now considered to belong to Neuquensaurus. This species may be a synonym of the contemporary sauropod Neuquensaurus australis.It was described by British paleontologist Richard Lydekker in 1893.Pilmatueia
Pilmatueia is a diplodocoid sauropod belonging to the family Dicraeosauridae that lived in Argentina during the Early Cretaceous.Tambatitanis
Tambatitanis is an extinct genus of titanosauriform dinosaur from the Early Cretaceous (probably early Albian) of Japan. It is known from a single type species, Tambatitanis amicitiae. It was probably around 14 meters long and its mass was estimated at some 4 tonnes. It was a basal titanosauriform and possibly belonged to the Euhelopodidae.Tastavinsaurus
Tastavinsaurus is a genus of sauropod dinosaur belonging to the Titanosauriformes. It is based on a partial skeleton from the Early Cretaceous of Spain. The type species is Tastavinsaurus sanzi, named in honor of the Rio Tastavins in Spain and Spanish paleontologist José Luis Sanz.Tengrisaurus
Tengrisaurus (meaning "Tengri lizard") is a genus of lithostrotian sauropod, from the Early Cretaceous (Barremian-Aptian), of the Murtoi Formation, Russia. It was described in 2017 by Averianov & Skutschas. The type species is T. starkovi.Vulcanodontidae
The Early Jurassic sauropod dinosaurs Zizhongosaurus, Barapasaurus, Tazoudasaurus, and Vulcanodon may form a natural group of basal sauropods called the Vulcanodontidae. Basal vulcanodonts include some of the earliest known examples of sauropods. The family-level name Vulcanodontidae was erected by M.R. Cooper in 1984. In 1995 Hunt et al. published the opinion that the family is synonymous with the Barapasauridae. One of the key morphological features specific to the family is an unusually narrow sacrum.