Gondwana Gondwana Gondwana (),(or Gondwanaland), was a supercontinent that existed from the Neoproterozoic (about 550 million years ago) until the Carboniferous (about 320 million years ago). It was formed by the accretion of several cratons. Eventually, Gondwana became the largest piece of continental crust of the Paleozoic Era, covering an area of about . During the Carboniferous, it merged with Euramerica to form a larger supercontinent called Pangaea. Gondwana (and Pangaea) gradually broke up during the Mesozoic Era. The remnants of Gondwana make up about two-thirds of today's continental area, including South America, Africa, Antarctica, Australia, and the Indian Subcontinent. The
Lungfish current distribution of modern lungfish species reflects extinction of many lineages subsequent to the breakup of Pangaea, Gondwana and Laurasia. Lungfish have historically been referred to as salamanderfish, but this term more often refers to "Lepidogalaxias salamandroides". All lungfish demonstrate an uninterrupted cartilaginous notochord and an extensively developed palatal dentition. Basal ("primitive") lungfish groups may retain marginal teeth and an ossified braincase, but derived lungfish groups, including all modern species, show a significant reduction in the marginal bones and a cartilaginous braincase. The bones of the skull roof in primitive lungfish are covered in a mineralized tissue called cosmine, but