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
Gondwana from all continents in the Southern Hemisphere, has a "Gondwanan distribution" and is often described as an archaic, or relict, lineage. The distributions in Proteaceae is, nevertheless, the result of both Gondwanan rafting and later oceanic dispersal. During the Silurian Gondwana extended from the Equator (Australia) to the South Pole (North Africa and South America) whilst Laurasia was located on the Equator opposite to Australia. A short-lived Late Ordovician glaciation was followed by a Silurian Hot House period. The End-Ordovician extinction, which resulted in 27% of marine invertebrate families and 57% of genera going extinct, occurred during this shift from