New species of moss discovered

A researcher from the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) has discovered a previously unknown species of moss - a remarkable feat since the mosses in the Alpine region are considered to be well researched

“I was extremely surprised to find a new moss species in a region as thoroughly studied as the European Alps,” remarked Thomas Kiebacher, a botanist at WSL. While conducting research in South Tyrol in August 2014, Kiebacher collected moss samples from a walnut tree under the assumption that he was gathering a commonly-found variety of moss, Orthotrichum schimperi. However, he noticed that the moss had hairs on the capsule hood (known as the calyptra), which was completely atypical for that species.

A few weeks later, Kiebacher’s colleague Michael Lüth found a moss in the Canton of Ticino that had the same characteristics as the South Tyrol moss. The botanists scoured the literature and found that the two specimens did not belong to any species known to science. In a project supported by the Museum of Nature South Tyrol, they then described the moss in the specialist publication Journal of Bryology.

Denticulate leaf apices

The new species is part of the genus of bristle-mosses (Latin: Orthotrichaceae). However, it has denticulate leaf apices, which is unusual for the genus. With that in mind, Kiebacher and Lüth decided to name it Orthotrichum dentatum – or ‘toothed bristle-moss’ in English. “The denticulate leaf apices and hairy calyptra are the main characteristics that set the new moss apart from similar species,” explained Kiebacher.

So far, the researchers have found O. dentatum in Ticino, Appenzell Ausserrhoden and South Tyrol. According to Kiebacher, “the new species is actually relatively common in the region, but since there are usually only a few small, five-millimetre moss plants on any given tree, you can hardly see them among all the other, much larger mosses”. O. dentatum grows on the nutrient-rich bark of broadleaf trees such as lime-trees and walnut trees and prefers open spaces in mountainous regions at altitudes of 500 to 1,400 m above sea level.