Psilotopsida
Translingual
Etymology
Psilotum + -opsida
Proper noun
Psilotopsida
- A taxonomic class within the subdivision Pterophyta – the whisk ferns.
Hyponyms
- (class): Psilotales, Ophioglossales - orders
References
Psilotopsida on Wikipedia.Wikipedia 
Psilotopsida on Wikispecies.Wikispecies - Polypodiopsida at the Tree of Life Web Project