Cystopteris diaphana (Bory) Blasdell (Woodsiaceae) - an overlooked native new to the British Isles?

摘要

Cystopteris diaphana (Bory) Blasdell (Diaphanous Bladder-fern) is repotted for the first time in the British Isles, This predominantly Macaronesian fern is locally abundant and appears native along nearly 1 km of the R. Camel, Cornwall (v.c. 2), whereit was discovered in February 2000, after being initially misidentified as C. fragilis (L.) Bernh. An ongoing critical reassessment of other. Bladder-fern records from S, W, England indicates that the species is also present on a Cornish hedgebank by alane at Penjerrick, Mawnan Smith (v.c. 1), from where it has been considered to be an escape from cultivation, and in a railway cutting near Tavistock, S, Devon (v.c. 3), where its status is uncertain. Historical reports of Cystopteris from similar habitats in the South-west suggest that the species may have been and possibly still could be more widely distributed.