Macronaria is a clade of sauropod dinosaurs. Macronarians are named after the large diameter of the nasal opening of their skull, known as the external naris, which exceeded the size of the orbit, the skull opening where the eye is located. Fossil evidence suggests that macronarian dinosaurs lived from the Middle Jurassic (Bathonian) through the Late Cretaceous (Maastrichtian). Macronarians have been found globally, including discoveries in Argentina, the United States, Portugal, China, and Tanzania. Like other sauropods, they are known to have inhabited primarily terrestrial areas, and little evidence exists to suggest that they spent much time in coastal environments. Macronarians are diagnosed through their distinct characters on their skulls, as well as appendicular and vertebral characters. Macronaria is composed of several subclades and families notably including Camarasauridae and Titanosauriformes, among several others. Titanosauriforms are particularly well known for being some of the largest terrestrial animals to ever exist.

Magyarosaurus is a genus of dwarf sauropod dinosaur from late Cretaceous Period in Romania. It is one of the smallest-known adult sauropods, measuring only 6 m (20 ft) in length and 750–1,000 kg (1,650–2,200 lb) in body mass. The type and only certain species is Magyarosaurus dacus. It has been found to be a close relative of Rapetosaurus in the family Saltasauridae in the sauropod clade Titanosauria in a 2005 study.