Cycadidae 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.

"[1] This subclass comprises the cycads, which include the two families Cycadaceae and Zamiaceae.

The following diagram shows a likely phylogenic relationship between subclass Cycadidae and the other Equisetopsida subclasses.

[2] Marchantiidae Bryidae Anthocerotidae Lycopodiidae Equisetidae Marattiidae Ophioglossidae Polypodiidae Cycadidae Ginkgoidae Gnetidae Pinidae Magnoliidae

This cycad article is a stub.