17" Fossil Titanosaur Sauropod (Alamosaurus) Metacarpal - Texas

Alamosaurus was a large North American titanosaurian sauropod from the latest Cretaceous period, approximately 70-66 million years ago. Alamosaurus would have been monstrously huge at adult size, but estimates vary. Material of fully grown individuals is scant, but scattered fossils that may have belonged to Alamosaurus indicate it was at least 80 feet in length, and around 25-35 tons. Higher estimates place it closer to 100 feet in length, making it roughly the same size as its South American cousins like Puertasaurus and Argentinosaurus.

Like all other sauropods, Alamosaurus was an herbivore, and stripped leaves off of plants with their peg-like teeth. Scattered remains of Alamosaurus are common in the southwest of North America, particularly the state of Texas. Its contemporaries would have been Tyrannosaurs, the hadrosaurid Kritosaurus, ceratopsians like Torosaurus and Bravoceratops, and the giant pterosaur Quetzalcoatlus.

This specimen was collected within the past year on private deeded property in Brewster County, Texas. You won't see any other dinosaur material from the Aguja & Javelina Formations for sale because nearly all of the formation lies the borders of Big Bend National Park or in Mexico, where laws prevent collection of fossils for sale. One of our partners was lucky enough to purchase several hundred acres of ranch land in Texas containing a good exposure of these formations.

These formations are equivalent age to the Judith River Formations in the Northern US and Alberta, Canada. Because relatively little collecting has been done on these formations in Texas, most of the species remain undescribed. Our partner has been putting important material into research collections and working with museums and researchers, so in the coming years their work will help lead to formal descriptions for these dinosaurs.