Pellaea glabella

Smooth cliffbrake
Conservation status
Secure  (NatureServe)
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Division:	Polypodiophyta
Class:	Polypodiopsida
Order:	Polypodiales
Family:	Pteridaceae
Genus:	Pellaea
Species:	P. glabella
Binomial name
Pellaea glabella Mett. ex Kuhn
Synonyms
Pellaea atropurpurea (L.) Link var. glabella (Mett. ex Kuhn) F.C.Gates Pellaea atropurpurea (L.) Link var. bushii Mack.

Pellaea glabella is a fern with the common name smooth cliffbrake. It was once regarded as a reduced form or variety of Pellaea atropurpurea. P. glabella is known to exist in two cryptic species, one diploid and one tetraploid. The diploid reproduces sexually, while the tetraploid is normally apogamous. It is now known that the tetraploid form of the species is one of the parents of the original hybrid P. × atropurpurea that became the apogamous species.