O is for…

Osmundaceae
A family of ferns who’s heritage takes us back nearly 300 million years to the very end of the Carboniferous.
Today there are only four extant genus in this family (Osmundastrum, Osmunda, Todea and Leptopteris) but the fossil record shows it was once a very much larger. Thamnopteris, Zalesskya, Chasmatopteris, Osmundacaulis, Aurealcaulis, Osmundites, Osmundopsis, Todites, Anomopteris, Osmundacidites and Paleosmunda are all fossil genera in the Osmundaceae. Certainly in the Jurasic Osmundaceae made up a large proportion of the understory in forests made up mostly of Araucaria, podocarps and taxodiaceae.
The Osmundaceae are represented in the fossil garden by Osmunda regalis, Osmunda claytoniana, O. japonica, O. banksiifolia, O. bromelifolia, Osmundastrum cinnamomium, O. cinnamomium var. asiaticum and Todea barbara.