Acrocanthosaurus

Acrocanthosaurus (ack-row-CAN-tho-SORE-us) was a very huge member of the Allosauridae family. It may stand for an evolutionary link between the Late Jurassic Allosaurus and the gigantic Late Cretaceous Carcharodontosaurus. Estimates rest its size at about 40 feet (12 meters) long and 13 feet (4 meters) tall. The only described species to date is A. atokensis.A. atokensis is branch of the Allosauroidea, a group which included Allosauridae, Sinraptoridae, and Carcharodontosauridae, along with basal allosaurids such as Monolophosaurus, Crylophosaurus, and Fukuiraptor ect.

Acrocanthosaurus could be secret with the Carcharodontosaurids or the Allosaurids. Allosauroiea was not related to the Tyrannosaur idea. Acrocanthosaurus was mainly noteworthy both for its size and for the low row of spines running along its back. The function of these spines leftovers unknown: they may have acted as muscle anchors or they may have supported a sail of skin.Even although Acrocanthosaurus had a sail, it was not a Spinosauroid.

J. Willis Stovall and Wann Langston, Jr. named it in 1950. The name means "high spine lizard", from the Greek akros ("high"), akantha ("spine") and sauros ("lizard"). It is from the Early Cretaceous of North America.