Ceratopteridaceae

Ceratopteridaceae
Scientific classification
Kingdom:	Plantae
Division:	Pteridophyta
Class:	Pteridopsida
Order:	Pteridales
Family:	Ceratopteridaceae
Genera
Ceratopteris Brongniart (4 to 6 species) Acrostichum L. (3 species)

Ceratopteridaceae is the family name for the clade that is now known to include the two genera Ceratopteris and Acrostichum. Although Ceratopteris was long isolated under its own family, due to adaptations for a dedicated aquatic existence, recent genetic study has determined that these two genera are allied. The former plant family name "Parkeriaceae" is no longer allowed in botanical nomenclature, due to the rule that higher taxa in plants must reflect their type division (in this case, genus). The only other acceptable classification for this clade would be to include it in a very broad Pteridaceae, which is here conserved only as the strict Pteris clade.