A new species of dandelion has been discovered growing on one of the remotest islands in the Outer Hebrides.
The plant is only known from the Isle of Hirta, in the archipelago of St Kilda, where it may be endemic and may be among the rarest plants in Scotland’s flora. It is thought that the plant could have been brought to St Kilda by birds or Vikings, and Iceland is thought to be the most likely source.
Seeds from four plants were collected two years ago by Jim McIntosh* when he joined a group of botanists from the Royal Botanic Garden Edinburgh (RBGE), on a sailing trip to the island of Hirta to carry out a survey of higher plants and bryophytes.
The seeds have been successfully propagated at the RBGE nursery by horticulturist Natacha Frachon. It is the presence of unique hairy exterior bracts on the flower bud that led botanists to believe it is a new species of Asteraceae, the largest family of flowering plants. The St Kilda dandelion is also much smaller than the common species.
The newly discovered dandelion has been named Taraxacum pankhurstianum for Richard Pankhurst, a retired staff member at RBGE who still carries out research work. He was involved in its culture and has been interested in the taxonomy, distribution and the computer-assisted identification of Taraxacum for more than thirty years.
When Richard, who is the vice-county recorder for the Outer Hebrides, heard about the trip in June 2010 he asked Jim McIntosh to collect any Taraxacum seed he saw while on his journey. Jim* works for the Botanical Society of the British Isles as coordinator for Scotland.
Richard said it is an honour to have the dandelion named after him. He added: “St Kilda is known to have two endemic species of mice and a wren, and now we know it has a dandelion too.’’ The dandelion was named by Professor John Richards, of Hexham, Northumberland, who saw the species and recognised that it was new.
Taraxacum may be rare on St Kilda because it is eaten by animals including sheep and perhaps, some birds. Also, botanists tend to visit St Kilda outside the very short dandelion season, which may peak in May on the island.
Hi-res images available on request
For further information or images, please contact Sandra Donnelly on 0131 248 1037 or Shauna Hay on 0131 248 2900
The species has just been named in the New Journal of Botany Volume 2 Number 1 2012.
The islands of St Kilda are the most westerly in the British Isles. Seeds were collected from four plants found at Village Bay, St Kilda from grassland on acidic soil.
The exterior bracts in T. Pankhurstianum are very hairy, particularly in early bud, a feature found in no other dandelion.
Dandelions are best adapted to colonise open ground rapidly.
The Royal Botanic Garden Edinburgh (RBGE) is a leading international research organisation delivering knowledge, education and plant conservation action in more than 80 countries around the world. In Scotland its four Gardens at Edinburgh, Benmore, Dawyck and Logan attract nearly a million visitors each year. It operates as a Non Departmental Public Body established under the National Heritage (Scotland) Act 1985, principally funded by the Scottish Government. It is also a registered charity, managed by a Board of Trustees appointed by Ministers. Its mission is “exploring and explaining the world of plants for a better future.” Learn more: www.rbge.org.uk