Belongs within: Apo-Spermatophyta. The Medullosales are a group of seed ferns known from the late Early Carboniferous to the Permian, generally reconstructed with an unbranching trunk crowned by fronds. At least some genera demonstrate dimorphism in leaf structure, with orbicular ‘Cyclopteris‘ leaves borne on basal parts of the trunk giving way to the pinnate fronds… Continue reading Trigonocarpales