''Cystopteris tennesseensis'', commonly known as the Tennessee fragile fern or Tennessee bladderfern, is a species of

fern The ferns (Polypodiopsida or Polypodiophyta) are a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. They differ from mosses by being vascular, i.e., having specialized tissue ...

in the family

Cystopteridaceae Cystopteridaceae is a family of ferns in the order Polypodiales. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), the family is placed in the suborder Aspleniineae of the order Polypodiales, and includes three genera. Alt ...

Description

''Cystopteris tennesseensis'' is a

lithophytic Lithophytes are plants that grow in or on rocks. They can be classified as either epilithic (or epipetric) or endolithic; epilithic lithophytes grow on the surfaces of rocks, while endolithic lithophytes grow in the crevices of rocks (and are also ...

fern, growing on calcareous rock ledges, scree, and cliffs. It has creeping rhizomes, and occasionally has misshapen bulbets. ''Cystopteris tennesseensis'' is a member of the

Cystopteris hybrid complex ''Cystopteris'' is a genus of ferns in the family Cystopteridaceae. These are known generally as bladderferns or fragile ferns. They grow in temperate areas worldwide. This is a very diverse genus and within a species individuals can look quite ...

. It originated as an allotetraploid hybrid between two diploid parents, '' C. bulbifera'' × '' C. protrusa''.

Distribution

The fern is native to the eastern United States. It occurs in the states of: Ala., Ark., Ga., Ill., Ind., Iowa, Kans., Ky., Md., Mo., N.C., Ohio., Okla., Pa., Tenn., Va., W.Va., Wis.

References

tennesseensis Ferns of the United States {{Polypodiales-stub