Crassigyrinus scoticus
Crassigyrinus (meaning "thick tadpole") was an early amphibian that lived during the early Carboniferous period. Crassigyrinus grew up to 2 meters in length, coupled with tiny limbs and unusually large jaws. Crassigyrinus is taxonomically enigmatic, having confused paleontologists for decades with its apparent fish-like and tetrapod features.