New species of ancient plant group discovered in South Africa.

Press release, 8 May 2009

A new species of an ancient group of plants known as quillworts has been discovered in a mountain-top pool in the heart of the Kamiesberg mountains in Namaqualand, South Africa.

The species, just 5 cm tall, has been given the Latin name Isoetes eludens, as it has eluded discovery until now, despite several searches for members of this plant group over many years in the area. Professor Stephen Hopper, Director of the Royal Botanic Gardens, Kew (RBG Kew), describes the quillwort, found during a research trip in October 2007, as “an exciting discovery of a species new to science in a beautiful part of South Africa”.

Professor Hopper said, “Together with colleagues from Kirstenbosch Botanical Garden, I had been studying the plants of granite outcrops of the Cape and Namaqualand since 2000. All the species we encountered on some seven trips over as many years were known to science, although some were recorded well north of their previously recorded geographical range. To discover a completely new species in a small pool just 2 m in diameter and 15 cm deep was an unexpected delight, highlighting how much more work is needed to reveal the full diversity of the Cape’s world-famous flora".

Professor Hopper and Dr Rhian Smith, also from RBG Kew, were about to descend the mountain at the end of a long day but at the last minute decided to climb onto one more ridge, as Hopper had a hunch there may be some interesting gnammas there (temporary rock pools, known by the local Nama people as !gau). His hunch was correct and the granite ridge contained a depression filled with water and a number of plants that were instantly recognisable as a type of quillwort. However, a closer look at the plant told him that this was something new and exciting.

Specimens were collected, along with some material for DNA analysis, and taken to Dr Koos Roux, Curator of the Compton Herbarium at the Kirstenbosch National Botanical Garden in Cape Town (part of the South African National Biodiversity Institute). Dr Roux is an expert in this group of plants and confirmed that the RBG Kew botanists had indeed discovered a new species of Isoetes. He then went on to provide a formal botanical description of the new species and this is published jointly with Professor Hopper and Dr Smith in this month’s edition of the scientific journal Kew Bulletin.

Quillworts are known from fossils aged more than 150 million years old. At this time, before flowering plants had evolved, quillworts were much more common. Today, there are about 150 known species, distributed on all continents except Antarctica. Most occupy permanent lakes and bogs, but several of the rarest occupy temporary pools and gnammas like the Kamiesberg Isoetes eludens.

One of the implications of the documentation of new species is that it allows them to be recognised for conservation. The remote !gau habitat of Isoetes eludens is not at risk from human encroachment but may face a larger threat from climate change. Exposed temporary pools are vulnerable to changes in climate such as decreased rainfall and as the Isoetes eludens !gau is the only confirmed location for the species its days may be numbered. However, according to Professor Hopper “plants are remarkably resilient in times of stress”.

He added: “The fossil record and recent genetic work on periglacial floras in Europe and semi-arid desert floras in Australia has shown that persistence in small microhabitats that serve as refuges during climate change has occurred frequently. Perhaps the new quillwort is one such survivor, and perhaps there are other as yet undiscovered populations in the Kamiesberg. It would be a great tragedy if neither of these ideas is true. Urgent collection of spores and long-term storage in seed banks would be an important next step to secure the conservation of this intriguing species of an ancient lineage".

Ends

For more infomation please contact the RBG Kew press office, telephone +44 (0)20 8332 5607 or e-mail pr@kew.org. Out of hours +44 (0)20 8332 5000.
Photography of Isoetes eludens is available

Notes to editors

The Royal Botanic Gardens, Kew is a world famous scientific organisation, internationally respected for its outstanding living collection of plants and world-class herbarium as well as its scientific expertise in plant diversity, conservation and sustainable development in the UK and around the world. Kew Gardens is a major international visitor attraction and its 132 hectares of landscaped gardens and its country garden, Wakehurst Place, attract nearly two million visitors every year. Kew was made a UNESCO World Heritage Site in July 2003 and celebrates its 250th anniversary in 2009.