Ledumahadi (meaning "a giant thunderclap" in Sesotho language) is a genus of lessemsaurid sauropodomorph dinosaur from the Early Jurassic Elliot Formation in Free State Province, South Africa. The type and only species is L. mafube, known from a singular incomplete postcranial specimen. A quadruped, it was one of the first giant sauropodomorphs, reaching a weight of around 12 tonnes (26,000 lb), despite not having evolved columnar limbs like its later huge relatives.
|Restoration of Ledumahadi mafube|
Apaldetti et al., 2018
McPhee et al., 2018
McPhee et al., 2018
Ledumahadi was likely a quadruped, as determined by analysis of the circumference of its humerus and femur compared to those of other dinosaurs. It would have had very large, robust forelimbs, consistent with those of its relatives. Unlike those of later sauropods, these limbs were naturally flexed, as opposed to being purely columnar.
At its time in the Early Jurassic epoch, Ledumahadi is thought to have been the largest land animal that had ever lived. It is estimated to have reached a maximum size of around 12 tonnes (26,000 lb) in weight; well over twice any confident weight estimates for a Triassic sauropod (around 3 tonnes, in Camelotia), and still significantly larger than the highest estimates for Lessemsaurus, around 7 tonnes; even early true sauropods, such as Vulcanodon, are not known to have been this large; L. mafube was more comparable to the later sauropod Diplodocus in weight.
A phylogenetic analysis of Ledumahadi mafube was performed by McPhee and colleagues, which found it to belong to a recently recognised clade of sauropodiformes called Lessemsauridae, including the closely related South African Antetonitrus and Lessemsaurus from Argentina. Another lessemsaurid described in 2018, Ingentia, could not be included in their analysis but was also recognised as belonging to Lessemsauridae. The results of McPhee and colleagues' analysis are shown in the cladogram below:
The size of the taxon was deemed to be important in the wider picture of sauropod evolution, similar to its other lessemsaurid relatives. Living only a few million years after the Triassic-Jurassic extinction event, it indicates that this event must have either had only a small effect on body size within the sauropod lineage, or may have not affected it at all. Significance was also found in the magnitude of the size itself—it lacked the columnar limbs that characterized its more derived relatives, thought to be a key adaptation in body size evolution. Ornithischian dinosaurs reach their largest sizes around a similar size of 12 to 17 tonnes in weight. This may have been the upper limit for dinosaurs without adopting the characteristics found in true sauropods, which grew to be several times the weight of Ledumahadi.
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.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.Daxiatitan
Daxiatitan is a genus of titanosaur dinosaur from the Lower Cretaceous of Lanzhou Basin, Gansu Province, northwestern China. It is known from fossils including several neck vertebrae, a shoulder blade, and a thigh bone.It was a very large dinosaur, estimated at 23–30 meters (75–98 feet). Like both Euhelopus and Huanghetitan, it had an enormously long neck.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.Huangshanlong
Huangshanlong is a genus of mamenchisaurid dinosaurs native to the Anhui province of China. It contains a single species, Huangshanlong anhuiensis. H. anhuiensis represents, along with Anhuilong and Wannanosaurus, one of three dinosaurs fround in Anhui province.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.Kaijutitan
Kaijutitan (meaning "Kaiju titan" after the type of Japanese movie monsters) is a genus of basal titanosaur dinosaur from the Sierra Barrosa Formation from Neuquén Province in Argentina. The type and only species is Kaijutitan maui.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.Oceanotitan
Oceanotitan is a genus of titanosauriform sauropod known from the Upper Jurassic Praia da Amoreira-Porto Novo Formation of Portugal. It contains one species, Oceanotitan dantasi.The holotype consists of the scapula, almost all of the pelvis, a complete leg sans the toes, and nine caudals.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.