Writing in the journal Science, the scientists say this dinosaur species is probably the only member so far found of a European group of Jurassic reptiles.
The biggest recorded dinosaur in the world is Argentinosaurus, a South American species that was twice as heavy.
Turiasaurus riodevensis was a herbivorous dinosaur, in spite of the ferocious appearance of its teeth.
Fossil remains were discovered in 2004 at Teruel in eastern Spain, and the scientists responsible, from the
Fundacion Conjunto Paleontologico de Teruel-Dinopolis, have now published a formal analysis of the find.
Teeth from theropod dinosaurs, Stegosaurus remnants, and fragments from fish and turtles were also found at the same site.
