Nearly worldwide, temperate and tropical regions.
Osmundaceae are considered intermediate in several respects between eusporangiate and leptosporangiate ferns. In the absence of sori, simultaneous maturation of spores, and development of sporangia from several initial cells, they are much like eusporangiate ferns. Their large prothalli with projecting antheridia are similar to those of leptosporangiate ferns.
Genera 3, species 16–36 (1 genus with 3 species and 1 hybrid in the flora).