Extinct gymnosperm order, included in the Coniferopsida, which appeared in early Carboniferous times and disappeared towards the end of the Permian. The cordaitaleans were trees up to 30 m high, with strap-like leaves and primitive cones. Some cordaitaleans developed stilt roots, probably lived in swamp habitats, and were analogous to modern mangroves. Fossils of stems, leaves, roots, and cones are locally abundant in coal. The term Cordaites is a form-genus name, and strictly applies to the leaves of cordaitaleans, but it has often been used informally for the whole plant. Other form-genera include Cordaianthus for cordaitean cones, Amelyon for the roots, and Dadoxylon, Araucarioxylon, Mesoxylon, and Pennsylvanioxylon, according to type or age, for stem fragments and wood.