High Quality Content by WIKIPEDIA articles! Torosaurus ("perforated lizard", in reference to the large openings in its frill) is a genus of ceratopsid dinosaur that lived during the late Maastrichtian stage of the Cretaceous period, between 66.8 and 65.5 million years ago. Fossils have been discovered across the Western Interior of North America, from Saskatchewan to south Texas. Torosaurus possessed one of the largest skulls of any known land animal. The frilled skull reached 2.6 metres (8.5 ft) in length. From head to tail, Torosaurus is thought to have measured about 9 m (30 ft) long and weighed 4 to 6 tonnes (4.4 to 6.6 tons). Torosaurus is distinguished from the contemporary Triceratops by an elongate frill with large openings (fenestrae), long squamosal bones of the frill with a trough on their upper surface, and the presence of five or more pairs of hornlets (epoccipitals) on the back of the frill.Torosaurus also lacked the long nose horn seen in Triceratops prorsus, and...