categoryZFerns Ferns List 

BRITTLE BLADDER-FERN

Cystopteris fragilis

Bladder-Fern Family [Cystopteridaceae]

category
category8Ferns
status
statusZnative
petals
petalsZ0
stem
stem8oval
stem
stem8fluted
toxicity
toxicityZmedium

22nd A[ril 2017, Loggerheads Country Pk, North Wales. Photo: © RWD
Grows in tufts, as here. Mainly growing in limestone areas, as here, on limestone rocks.


22nd A[ril 2017, Loggerheads Country Pk, North Wales. Photo: © RWD
The leaves are on the greyish side of green (but not as greyish as it appears here (which was taken in the shade where the colour temperature of the light might be somewhat higher than the camera is programmed for).


22nd A[ril 2017, Loggerheads Country Pk, North Wales. Photo: © RWD
The leaves grow to 25cm long including the stalk (occasionally up to 45cm).


22nd A[ril 2017, Loggerheads Country Pk, North Wales. Photo: © RWD
The leaves here are usually 2-pinnate, the final leaflet being lobed [although they can be 3- or even 4-pinnate]. Here you can see the veins in each leaflet.


22nd A[ril 2017, Loggerheads Country Pk, North Wales. Photo: © RWD
From their upper surface the rachis is grooved (but from below is rounded).


22nd A[ril 2017, Loggerheads Country Pk, North Wales. Photo: © RWD
The underside of the frond: the half-round rachis. Near the end of the frond: the cases of the spores are white, the spores themselves black (when ripe) [groove on other side]. Here in April they are at a very young stage, it needs to be much later on in the season.


22nd A[ril 2017, Loggerheads Country Pk, North Wales. Photo: © RWD
There is usually one spore case per lobe.


Brittle Bladder Fern exists as either of two subspecies:

  • Cystopteris fragilis ssp. fragilis which is the far the most frequent growing in shady limestone rocks or walls or in roccky woods on basic soils. The leaves lack glandular hairs.
  • Cystopteris fragilis ssp. huteri which is a very rare [RRR] found only rocky mountain gullies in Snowdonia, North Wales since 1830. The leaves have scattered glandular hairs and more-dissected leaves but which lack the notches present in the apexes of the pinnules of ssp. fragilis.

Some similarities to : Lanceolate Spleenwort (Asplenium obovatum), Scottish Lady-Fern (Athyrum flexile) [RR] and less so to Wall-rue (Asplenium ruta-muraria).


  Cystopteris fragilis  ⇐ Global Aspect ⇒ Cystopteridaceae  

Distribution
 family8Bladder-Fern family8Cystopteridaceae
 BSBI maps
genus8Cystopteris
Cystopteris
(Bladder-Ferns)

BRITTLE BLADDER-FERN

Cystopteris fragilis

Bladder-Fern Family [Cystopteridaceae]