Салтазавр: Қаңқасы қоршалған динозавр

Extinct genus of dinosaurs

Saltasaurus (which means "lizard from Salta") is a genus of saltasaurid dinosaur of the Late Cretaceous period of Argentina. Small among sauropods, though still heavy by the standards of modern creatures, Saltasaurus was characterized by a short neck and stubby limbs. It was the first genus of sauropod known to possess armour of bony plates embedded in its skin. Such small bony plates, called osteoderms, have since been found on other titanosaurians.

The fossils of Saltasaurus were excavated by José Bonaparte, Martín Vince and Juan C. Leal between 1975 and 1977 at the Estancia "El Brete". The find was in 1977 reported in the scientific literature. Saltasaurus was named and described by Bonaparte and Jaime E. Powell in 1980. The type species is Saltasaurus loricatus. Its generic name is derived from Salta Province, the region of north west Argentina where the first fossils were recovered. The specific name means "protected by small armoured plates" in Latin. The holotype, PVL 4017 92, was found in a layer of the Lecho Formation dating from the early Maastrichtian stage of the Upper Cretaceous period, about seventy million years old. It consists of a sacrum connected to two ilia. Under the inventory number PVL 4017 over two hundred additional fossils have been catalogued. These include rear skull elements, teeth, vertebrae of the neck, back, hip and tail, parts of the shoulder girdle and the pelvis, and limb bones — plus various pieces of armour. These bones represent a minimum of five individuals, two adults and three juveniles or subadults. Currently the only recognised species of Saltasaurus is S. loricatus. A S. robustus and a S. australis have been suggested but these are now considered to belong to a separate genus, Neuquensaurus. Earlier, armour plates from the area had been named as Loricosaurus by Friedrich von Huene who assumed them to be from an armoured ankylosaurian. It has been suggested these plates were in fact from Saltasaurus.

Saltasaurus is very small compared to most other members of the Sauropoda. Powell estimated the adult length at six metres. In 2010, Gregory S. Paul estimated the maximum length at 8.5 metres (28 ft), the weight at 2.5 tonnes (2.8 short tons). The teeth of Saltasaurus were cylindrical, with spatulate points. Saltasaurus had a relatively short neck with shortened neck vertebrae. The vertebrae from the middle part of its tail had elongated centra.

Saltasaurus in a cladogram after Navarro et al., 2022:

Like all sauropods, Saltasaurus was herbivorous. Because of its barrel like rump, shaped like a hippopotamus, Powell suggested that Saltasaurus was aquatic. Despite its small stature, Saltasaurus was still graviportal like other sauropods, meaning it could not run because its hindlimbs had to be held straight at the load bearing phase of their walking cycle. Powell assumed adult individuals were protected against predators by their body armour, while juveniles were protected by the herd as a whole.