| | Ferns (Filicopsida) of Britain and Ireland |
Cystopteris fragilis subsp. dickieana (Sim) Hylander
Sporophyte. The rhizomes rather stout; more or less decumbent; bearing scales (these thin, brown, lanceolate). Plants with no clear distinction into fertile and sterile leaves.
Leaves aggregated terminally; to 5–20(–35) cm long; dying in the autumn; circinnate; compound; complexly divided; bipinnate with more or less undivided pinnules. Pinnae 5–15 on each side of the leaf (? - “up to 15”). The leaves not as in Pteris (q.v.). The petioles shorter than the blades to about as long as the blades (from a third as long, slender and brittle, dark brown at the base and paler above, with a few scales at the base and usually a few hair-like scales above). Leaf blades in outline lanceolate. The longest pinnae about a third of the distance from the base of the blade to around the middle of the blade; 1–4 cm long. The adjacent pinnae strongly overlapping. The venation of the lamina open.
The sporangia superficial; protected; aggregated in sori. The sori sub-orbicular (small, each on a receptacle with a vascular strand from the vein, with a row of several borne on either side of the midrib of the pinnule); remaining discrete at maturity; with a true indusium. The indusia not reniform but flap-like from the base of the sorus, vaulted at first, later reflexed. The mature spores rugose; without a perispore.
Distribution and habitat. On base-rich substrates. Associated with basic rocks in maritime caves and stream-gorges. Kincardines, Easterness and mid-Perthshire.
Vice-county records. Britain: Mid Perthshire, East Perthshire, Kincardineshire, South Aberdeenshire, Banffshire, East Inverness-shire.
Classification. Family Polypodiaceae (C.T.W.); Cystopteridaceae (Swale and Hassler); Woodsiaceae (Stace). Order Athyriales (Swale and Hassler).
Illustrations. • C. dickieana: as C. alpina var. dickieana, Eng. Bot. 1867 (1886). • C. dickieana: Sowerby and Johnson (1859). • Cystopteris species (inter alia). Thelypteridaceae. 1721, Oreopteris limbosperma. Dryopteridaceae. 1722, Dryopteris filix-mas; 1723, Dryopteris submontana; 1724, Dryopteris cristata; 1725, Dryopteris carthusiana; 1726, Dryopteris dilatata; 1727, Dryopteris aemula. 1728, Polystichum lonchitis; 1729 and 1730, Polystichum aculeatum; 1731, Polystichum setiferum. CYSTOPTERIDACEAE. 1732, Cystopteris fragilis; 1733, C. fragilis var. angustata; 1734, C. fragilis var. dentata; 1735, Cystopteris alpina; 1736, Cystopteris montana; 1737, Cystopteris dickieana. Athyriaceae. 1738, Athyrium filis-femina. Aspleniaceae. Asplenium fontanum; 1740, Asplenium obovatum subsp. lanceolatum. From Sowerby and Johnson (1863, the family assignments following Swale and Hassler).
We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, and distributions of character states within any set of taxa. See also Guidelines for using data taken from Web publications.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2004 onwards. Ferns (Filicopsida) of Britain and Ireland. Version: 5th August 2019. delta-intkey.com’.
