Losillasaurus Facts
| Diet | Herbivore |
| Height | 5m |
| Length | 16m |
| Weight | 13.5 tonnes |
| Environment | Land |
| Era | Jurassic |
| Period | Late Jurassic |
| Type | Sauropod |
| Location | Spain |

| Diet | Herbivore |
| Height | 5m |
| Length | 16m |
| Weight | 13.5 tonnes |
| Environment | Land |
| Era | Jurassic |
| Period | Late Jurassic |
| Type | Sauropod |
| Location | Spain |
Losillasaurus giganteus was a massive sauropod dinosaur that thundered across southeastern Spain during the Late Jurassic period, approximately 154-152 million years ago. This enormous herbivore represents one of Europe's largest known dinosaurs, with fossil remains discovered in the Villar del Arzobispo Formation near Valencia. Despite being known from a subadult specimen, Losillasaurus already demonstrated impressive proportions that rival some of the world's largest dinosaurs.
As a typical sauropod, Losillasaurus possessed the classic long-necked body plan with a small head, elongated neck, barrel-shaped body, and whip-like tail. The creature walked on four pillar-like legs and used its extended neck to browse vegetation from treetops that other herbivores couldn't reach. Its powerful limbs, including a remarkable 143-centimetre-long humerus bone, supported its massive frame as it moved through the lush Late Jurassic landscapes of ancient Spain.
Losillasaurus belongs to the Turiasauria, a group of sauropods particularly common in Europe during the Late Jurassic and Early Cretaceous periods. Like other sauropods, it was a peaceful giant that spent most of its time feeding on ferns, conifers, and other available vegetation. Its teeth were designed for stripping leaves rather than chewing, so it likely swallowed stones to help grind up plant material in its stomach.
The holotype specimen includes remarkably complete remains, featuring skull fragments, vertebrae from the entire spine, limb bones, pelvic elements, and even sternal plates. This comprehensive fossil material makes Losillasaurus one of the best-known large sauropods from Europe, providing valuable insights into the diversity of these magnificent giants that once roamed the continent.
Losillasaurus was characterised by the distinctive dimension and shape of the neural spines on its proximal caudal vertebrae near the base of its tail. Its enormous humerus bone, measuring 143 centimetres in length, was proportionally massive even for a sauropod of its size.
Like other sauropods, Losillasaurus was likely a peaceful browser that moved in herds across Late Jurassic Spain. It would have spent most of its day feeding, using its long neck to reach high vegetation and potentially rearing up on its hind legs to access the tallest trees.
Losillasaurus was first described by Casanovas, Santafé, and Sanz in 2001. The original fossils were discovered at Villar del Arzobispo Formation, Valencia, Spain.