Macrocollum suture. "Macrocollum", alongside "Jaklapallisaurus" and "Unaysaurus", was found to belong to the clade Unaysauridae. "Macrocollum" lived between about 225.42 to 225 million years ago, in the Norian age of the late Triassic period. It was found in the south of Brazil, which at the time was connected to northwest Africa. At the time, most of the Earth's landmass was united into the supercontinent Pangaea, which was just starting to divide into Laurasia in the north, and Gondwana in the south. U-Pb (Uranium decay) dating found that the Caturrita Formation dates to around 225.42 million years ago, making it fewer than
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