Osmundales

The Osmundales is an order of ferns, and the Osmundaceae family, also known as the royal fern family, is the only family within this order. This is a primitive group that includes three living genera of large ferns: Osmunda, Todea, and Leptopteris, with about 20 species in total. Fossil records indicate the existence of extinct genera dating back to the Late Permian Period, around 260 million years ago.1

A key characteristic of Osmundaceae is their spore-producing structures, called sporangia. These are either scattered or clustered (sori) on the leaflets or special fertile parts of the fronds. Unlike many other fern families, these sori lack a membranous covering called an indusium. The genera are differentiated by how their sporangia and sori are arranged.1

Economically, the fibrous roots of Osmunda species are used as a growing medium for orchids and other epiphytic plants. Some species, like the cinnamon fern and interrupted fern, are also popular as ornamental plants in greenhouses and gardens.12