Mawsonia is an extinct genus of prehistoric coelacanth fish, and the largest of this group, ranging from an estimated 3.5 metres (11.5 feet) up to 6.3 metres (20.7 feet) long.[2][3] It lived during the latest Jurassic to Cretaceous periods (Tithonian to Cenomanian stages, about 152 to 99 million years ago) of South America and Africa. Mawsonia was first described by British paleontologist Arthur Smith Woodward in 1907.[4]