Maastrichtian

The Maastrichtian is, in the ICS geologic timescale, the latest age of the Upper Cretaceous. It spanned the interval from 72.1 to 66 million years ago. The breakup of Pangaea was nearly complete in the Maastrichtian, with Australia beginning to break away from Antarctica and Madagascar breaking away from India. However, Arabia had not yet rifted away from Africa. North America was separated from Europe by rift basins, but seabed spreading had not yet commenced between the two continents. 
Paleontology.
Dinosaurs.
Dinosaurs remained the dominant large terrestrial animals throughout the Maastrichtian, though mammals with internal organs similar to modern mammals were also present.
Flora.
The radiation of flowering plants was well under way in the Maastrichtian. From 50% to 80% of all genera of land plants were angiosperms, though gymnosperms and ferns still covered larger areas of the land surface.