 Paleobotany applied to freshwater plants is a field of paleontology that reveals evolutionary trends distinct from terrestrial and marine flora, with notable groups such as cyanobacteria and persinophytes in the Precambrian, green algae in the Paleozoic, carophytes in the Permian to early Cretaceous, and freshwater angiosperms in the late Cretaceous and tertiary. This article was authored by C. Martin Closes.