''Cystopteris fragilis'' is a species of
perennial
In horticulture, the term perennial ('' per-'' + '' -ennial'', "through the year") is used to differentiate a plant from shorter-lived annuals and biennials. It has thus been defined as a plant that lives more than 2 years. The term is also ...
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 ...
known by the common names brittle bladder-fern
and common fragile fern. It can be found worldwide, generally in shady, moist areas.
Description
It has a short, black rootstock. The leaves are up to 5-25 cm and are borne on fleshy
petioles with few or no long hairs. The petioles are about half the length of the leaf blade. Each leaf is divided into many pairs of leaflets, each of which is subdivided into lobed segments. The leaflets are narrowly triangular and
apiculate. The underside of the leaf has many rounded
sori containing the
sporangia
A sporangium (from Late Latin, ; : sporangia) is an enclosure in which spores are formed. It can be composed of a unicellular organism, single cell or can be multicellular organism, multicellular. Virtually all plants, fungus, fungi, and many ot ...
. A young ''Cystopteris fragilis'' is said to have the scent of
bitter almond, which is caused by spores that contain
hydrogen cyanide
Hydrogen cyanide (formerly known as prussic acid) is a chemical compound with the chemical formula, formula HCN and structural formula . It is a highly toxic and flammable liquid that boiling, boils slightly above room temperature, at . HCN is ...
.
Habitat
The plant, native to for example Finland, grows in places fit for its brittle structure: usually shady and slightly moist areas, in the cracks and ledges of vertical rock faces, blockfields and sometimes on even cliff surfaces as well. It avoids the more most acidic and barren cliffs and prefers especially slightly lime rich soil.
Gallery
Image: Cystopteris fragilis iNat-154978453.1.jpg, Icicle Creek, WA
Image: Cystopteris fragilis iNat-154978453.2.jpg, Adaxial leaf
Image: Cystopteris fragilis iNat-154978453.3.jpg, Abaxial leaf
References
External links
Jepson Manual Treatment: ''Cystopteris fragilis''USDA Plants Profile: ''Cystopteris fragilis''Flora of North America: ''Cystopteris fragilis''''Cystopteris fragilis'' — U.C. Photo gallery
fragilis
Ferns of Asia
Ferns of Europe
Ferns of the Americas
Ferns of Canada
Ferns of the United States
Ferns of California
Flora of England
Flora of Finland
Flora of Lebanon
Flora of Russia
Flora of the Sierra Nevada (United States)
Flora of South Georgia Island
Biota of South Georgia and the South Sandwich Islands
Plants described in 1805
{{Polypodiales-stub