A scientist’s three-decade quest to find a rare moss thought to be extinct in Scotland has ended with the discovery of the plant in the Borders.
Water rock-bristle was last found north of the border in the late 1940s and it was feared to have died out after a series of expeditions led by bryologist Dr David Long, from the Royal Botanic Garden Edinburgh, failed to turn up any sign of it.
However, this past autumn, Dr Long’s three-decade quest finally ended with the discovery of dark-green shoots of the tiny moss on a limestone boulder, next to a burn, near Newcastleton.
The moss, whose Latin name is seligeria carnoilica, has also been recorded at a site in Northumberland and at a clutch of locations in Slovenia and Sweden. But its rarity is such that very little is known about it. Water rock-bristle was first identified in Scotland at the Black Burn, near Newcastleton, by bryologist Evelyn Lobely in 1948. But despite returning on a number of occasions to where she thought she found it originally, she could find no trace of the moss again.
Dr Long found the moss with a group from the British Bryological Society when they explored a new area of the burn in September, during a period the water level was very low.
He told The Southern this week that the Borders is surprisingly rich in bryophytes – mosses, liverworts and hornworts – due to the diversity of habitats and climatic conditions, plus the clean air and water.
“For example, on the Berwickshire coast are found several Mediterranean mosses, which only just reach north into Scotland,” he said.
“The high tops of the Tweedsmuir Hills are rich in mountain species typical of the Scottish Highlands, and the Newcastleton area has the double bonus of high rainfall, favouring western oceanic species, and limestone outcrops with their specialities such as the water rock-bristle moss.
“We can certainly expect to find a few more new rarities in all those special places,” added Dr Long.