Huayracursor: “The Ancestor” of Super Long-Necked Dinosaurs in the Andes of South America!

In a landmark 2025 discovery that has rewritten sauropod origins, paleontologists have unveiled Huayracursor jaguensis—the earliest known dinosaur showing the first steps toward the iconic long neck and giant body size of later sauropods. Unearthed in the remote Andes of northwestern Argentina, this “wind runner” (from Quechua) lived 230 million years ago during the Carnian stage of the Late Triᴀssic.

Described in Nature (October 15, 2025) by Martín Hechenleitner and colleagues, the nearly complete skeleton comes from the newly recognized Northern Precordillera Basin at Quebrada Santo Domingo in La Rioja province. At roughly 3–4 meters long, Huayracursor was already significantly larger than its Carnian contemporaries and displayed the first signs of cervical vertebral elongation—positioning it as a crucial intermediate between small, short-necked early sauropodomorphs and the colossal, long-necked giants that dominated the Jurᴀssic.

This find provides the oldest direct evidence that increased body mᴀss and neck lengthening evolved synchronously at the very dawn of Sauropodomorpha. ᴀssociated fossils of rhynchosaurs, cynodonts, and aetosaurs paint a rich picture of a previously unknown Andean Triᴀssic ecosystem.

Experts hail Huayracursor as the “missing link” that illuminates how the lineage leading to Argentinosaurus and other тιтans began its evolutionary journey in South America’s mountains. From the high Andes, this pioneering dinosaur emerges as the true ancestor of the longest-necked creatures ever to walk the Earth—proof that the age of giants started far earlier, and farther south, than anyone imagined. Paleontology’s sauropod story just gained its most exciting early chapter!