Erketu is the name given to a genus of dinosaur from the Late Cretaceous (Cenomanian - Santonian). It was a sauropod with the longest neck relative to its body size. Its fossils were found in Mongolia.
The type species, Erketu ellisoni, was described in March 2006 by Daniel Ksepka and Mark Norell of the American Museum of Natural History. Its neck was estimated to be twice as long as its body, which may be a record for neck to body ratio. The exact ratio is unknown, because no dorsal vertebrae of E. ellisoni have been reported, although some hindlimb material suggests the approximate size of the body. The long neck of Erketu is the result of the individual vertebrae being greatly elongated; it is unknown if the number of cervical vertebrae was increased. Erketu is also diagnosed by bifurcate anterior cervical neural spines, another unusual trait for a titanosauriform. A phylogenetic analysis of sauropods indicates that Erketu is a basal somphospondylian (the clade of all macronarians closer to titanosaurs than to brachiosaurs), and is most closely related to Titanosauria.
This particular sauropod species is named after the American Museum of Natural History's resident paleo-artist, and close friend of Mark Norell, Mick Ellison.
Temporal range: Early Cretaceous
|Holotypic cervical vertebrae of Erketu ellisoni (IGM 100/1803; D, E) in left lateral view|
Ksepka & Norell, 2006
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.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.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.Erketü Qatun
Erketü Qatun (English: Powerful Queen) (ca. 1551–1612), also referred to as the Third Lady (Chinese: 三娘子） , was an influential member of the Borjigin clan in late 16th century and early 17th century Mongolia. Her real name is unknown, only being remembered by a title bestowed upon her. She was the wife of four subsequent leaders of the Tümed, and her pro-Ming Empire views kept the longest peace between the two competing powers. She is also known as Sanniangzi.Euhelopodidae
Euhelopodidae is a family of sauropod dinosaurs which includes the genus Euhelopus. All known euhelopodids lived in what is now East Asia. The family name was first proposed by American paleontologist Alfred Sherwood Romer in 1956. The four genera Chiayusaurus, Omeisaurus, Tienshanosaurus, and Euhelopus were the original proposed euhelopodines (subfamily Euhelopodinae). Other genera such as Mamenchisaurus and Shunosaurus were formerly placed within this family, but these are now regarded as more basal sauropods.
Michael D'Emic (2012) formulated the first phylogenetic definition of Euhelopodidae, defining it as the clade containing "neosauropods more closely related to Euhelopus zdanskyi than to Neuquensaurus australis". Below is a cladogram presenting the cladistic hypothesis of Euhelopodidae proposed by D'Emic.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.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.Qiaowanlong
Qiaowanlong is a genus of sauropod dinosaur. Fossils belonging to the genus were found in 2007 from the Yujinzi Basin of Gansu, China, and were described in 2009 in the Proceedings of the Royal Society B. The remains come from a geological formation called the Xinminpu Group, dating to the Early Cretaceous (Albian stage) about 100 Ma. The only known specimen consists of articulated cervical (neck) vertebrae and a right pelvic girdle, as well as several unidentified bone fragments. Qiaowanlong was initially reported as the first brachiosaurid to have been found from China. However, later analysis found that it was more closely related to titanosauriformes like Euhelopus and Erketu. It is estimated to have had a length of around 12 metres (39 ft) and would have weighed around 6 tonnes. The type species is Q. kangxii.Ruyangosaurus
Ruyangosaurus (Ruyang County lizard) 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. Along with Huanghetitan and Daxiatitan, Ruyangosaurus is among the largest dinosaurs discovered in Cretaceous Asia.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.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.Yunmenglong
Yunmenglong is an extinct genus of somphospondylan sauropod known from the late Early Cretaceous of Henan Province, central China. Its remains were discovered in the Haoling Formation of the Ruyang Basin. The type species is Yunmenglong ruyangensis, described in 2013 by Junchang Lü et al. on the basis of an incomplete postcranial skeleton. Yunmenglong shares some characters with Euhelopus, Qiaowanlong and Erketu, and a phylogenetic analysis places it as a sister taxon of Qiaowanlong, both grouped with Erketu in a position more derived than Euhelopus but basal to Titanosauria. Yunmenglong represents the first long-necked sauropod dinosaur recorded from central China to date.