Scottish scurvygrass  (Cochlearia officinalis subsp. scotica)

Scottish scurvygrass

Facts

Kingdom Plantae
Phylum Anthophyta
Class Magnoliopsida
Order Capparales
Family Brassicaceae
Genus Cochlearia (1)
Size Flower diameter: 5 - 6 mm (2)
Diameter of tufts: 5 - 10 cm (2)

Status

Classified as Taxonomically Uncertain (3).

Description

There is currently disagreement as to the taxonomic status of Scottish scurvygrass. It was, at one point, held to be a species its own right (2)(3); at present, however, it is thought to be a subspecies of common scurvygrass (Cochlearia officinalis) which is endemic to the British isles (4). More recently it has been suggested that populations identified as subspecies scotica may actually represent individuals of other scurvygrasses that have been dwarfed by harsh environmental conditions (4). This confusion arises because as a group, the scurvygrasses are highly variable in response to environmental stresses (3). Until further research is carried out into the taxonomy of Scottish scurvygrass, and the current mystery resolved, it is widely treated as a subspecies of common scurvygrass Cochlearia officinalis scotica (4). This plant produces small compact tufts that measure up to 10 cm in diameter. The basal leaves have long stalks and are variable in shape. The flowers have pale mauve petals, and the fruit narrows at each end (2).

Range

There have been very few recent records of Scottish scurvygrass because the confusion over its taxonomy has understandably made recorders reluctant to identify it (4). Most records are from coastal areas northwards from the Isle of Man and Berwick, the Inner and Outer Hebrides, Orkney and Shetland, with other records from Easter Ross, Ireland and the Scilly Isles (3).

Habitat

Found in a range of coastal habitats including crevices in boulders near the sea, sand dunes, grazed grasslands on saltmarshes and cliff-tops and on open stony shores (4).

Biology

Scottish scurvygrass occurs as either a biennial or perennial.

Threats

Potential threats include coastal development and pollution, as well as the possible effects of climate change (3).

Conservation

Scottish scurvygrass is listed as a priority species under the UK Biodiversity Action Plan (UK BAP). The most pressing requirement at present is for the taxonomic status of this plant to be resolved. If it confirmed as an endemic subspecies rather than environmentally dwarfed forms of other scurvygrasses, action needs to be taken to conserve it. The range and abundance of the plant will need to be determined and monitoring will be initiated (3).

Authentication

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
arkive@wildscreen.org.uk

Biennial: A plant that lives for two years and typically flowers only in the second year.
Endemic: a species or taxonomic group that is only found in one particular country or geographic area.
Perennial: plants that live for at least three seasons; after an initial period they produce flowers once a year.
Subspecies: a population usually restricted to a geographical area that differs from other populations of the same species, but not to the extent of being classified as a separate species.

References

  1. National Biodiversity Network Species Dictionary (September 2003):
    http://www.nhm.ac.uk/nbn
  2. Clapham, A.R., Tutin, T.G. & Moore, D.M. (1987) Flora of the British Isles: 3rd Edition. Cambridge University Press, Cambridge.
  3. UK BAP Species Action Plan (October 2003):
    http://www.ukbap.org.uk
  4. Preston, C.D., Pearman, D.A. & Dines, T.D. (2002) New Atlas of the British and Irish Flora. Oxford University Press, Oxford.