Malestrom is a Pliosaur.
Ice Age 2 (2006)
During the melting 2 sea dinosaurs called Cretaceous and Maelstrom are released. During the flood they try to kill Manny. But Cretaceous and Maelstrom get crushed by a boulder! BUT just before the boulder hit the ground Cretaceous and Maelstrom got out of the way and got washed away with the floodwater.