What is "polypodiidae"

Polypodiidae may refer to:

• Polypodiidae (family), a zoological family that only includes Polypodium hydriforme, a cnidarian parasite of fish eggs
• Polypodiidae (plant) – Polypodiidae sensu Chase & Reveal, 2009 – a botanical subclass of Equisetopsida sensu lato that includes the leptosporangiate ferns
• Polypodiidae , a botanical subclass that only includes the fern family Osmundaceae

Polypodiidae is a subclass of Equisetopsida in the sense used by Mark W. Chase and James L. Reveal in their 2009 article "A phylogenetic classification of the land plants to accompany APG III." This subclass comprises leptosporangiate ferns. It is equivalent to the class Polypodiopsida in previous treatments, including Smith et al., 2006.