Anostraca the Gondwana fragmentation closely echoes the current distribution of the order. Presently, Anostraca are found on all seven continents. Most of the extant genera have restricted geographical distributions. Only three genera are widespread across the remnants of the former supercontinent Pangaea: "Artemia", "Branchinella" and "Branchinecta", while the remaining genera are found only throughout former Laurasia. This suggests that much of the potential habitat in this supercontinent, now occupied by Anostraca, to have been unoccupied by ecologically similar species, or to have been inhabited by species with less adaptive ability. Studies have found Anostraca capable of rapid colonization and speciation. Anostraca
Phanerozoic of Pangaea into Laurasia and Gondwana in an extinction known as the Jurassic-Cretaceous extinction. Sea levels rose, destroying fern prairies and creating shallows. Ichthyosaurs became extinct whereas sauropods, as a whole, did not; in fact, some species, like "Titanosaurus", lived until the K-T extinction. The increase in sea-levels opened up the Atlantic sea way which would continue to get larger over time. The divided world would give opportunity for the diversification of new dinosaurs. The Cretaceous is the longest period in the Mesozoic, spans from 145 million to 66 million years ago, and is divided into two epochs: Early Cretaceous,