MEANING: Jiangxi giant
PERIOD: Late Cretaceous
CONTINENT: Asia
Jiangxititan is a titanosaurian sauropod from the Late Cretaceous of China. Typical for a sauropod, it had a long neck and stood on four pillar-like legs to support its massive body. Jiangxititan is a member of the Lognkosauria, which include some of the largest dinosaurs known, and is one of the few from mainland Asia.
Abstract from paper: Jiangxititan ganzhouensis gen. et sp. nov. is a new titanosaurian sauropod recovered from the Upper Cretaceous (Maastrichtian) Nanxiong Formation of Jiangxi Province, southern China. It is characterised by: (1) posterior cervical and anterior dorsal centra strongly compressed dorsoventrally; (2) accessory horizontal laminae present within the anterior dorsal pleurocoels; (3) posterior cervical and anterior dorsal neural arches low; (4) posterior cervical and anterior dorsal neural spines deeply bifurcated and widely separated; (5) inverted ‘V’ lamina formed by the left and right medial spinoprezygapophyseal laminae present at the anterior margin of the bifid point in posteriormost cervical and anteriormost dorsal neural spines; (6) triangular fossa formed by the metapophysis, medial and lateral spinoprezygapophyseal laminae present at the anterior margins of the posteriormost cervical and anteriormost dorsal neural spines; (7) postzygapophyses in the posterior cervical vertebrae fan-shaped; (8) medial and lateral spinopostzygapophyseal laminae present in the anterior dorsal vertebrae; and (9) anterior dorsal rib short and gracil. Our phylogenetic analysis places Jiangxititan within the deeply-nested titanosauriform clade Lognkosauria and the sympatric Gannansaurus in a much earlier-diverging lineage. This new discovery thus demonstrates the presence of both early-diverging and late-diverging titanosauriform sauropods in the Late Cretaceous Ganzhou dinosaur fauna.
Jiangxititan is from the Cretaceous. The Cretaceous is a geological period that lasted from about 145 to 66 million years ago. It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin creta, "chalk", which is abundant in the latter half of the period.
The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now-extinct flora and fauna, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Earth by the end of the Cretaceous, coincident with the decline and extinction of previously widespread gymnosperm groups.
The Cretaceous (along with the Mesozoic) ended with the Cretaceous–Paleogene extinction event, a large mass extinction in which many groups, including non-avian dinosaurs, pterosaurs, and large marine reptiles, died out. The end of the Cretaceous is defined by the abrupt Cretaceous–Paleogene boundary (K–Pg boundary), a geologic signature associated with the mass extinction that lies between the Mesozoic and Cenozoic Eras.
Jiangxititan is a sauropod. Sauropods are saurischian dinosaurs that had very long necks, long tails, small heads (relative to the rest of their body), and four thick, pillar-like legs. They are notable for the enormous sizes attained by some species, and the group includes the largest animals to have ever lived on land. Well-known genera include Brachiosaurus, Diplodocus, Apatosaurus and Brontosaurus.
The oldest known unequivocal sauropod dinosaurs are known from the Early Jurassic, and by the Late Jurassic (150 million years ago), sauropods had become widespread. By the Late Cretaceous, one group of sauropods, the titanosaurs, had replaced all others and had a near-global distribution. This group included the largest animals ever to walk the earth. Estimates vary, but the largest titanosaurs are estimated at upward of around 40 m, and weighing 100 t, or possibly even more.
As with all other non-avian dinosaurs alive at the time, the titanosaurs died out in the Cretaceous–Paleogene extinction event. Fossilized remains of sauropods have been found on every continent, including Antarctica.