Sphagnum riparium
Sphagnum riparium Ångstr.
Sphagnaceae
Conservation status. Critically Endangered [CR B2ab(iii)].
Morphology and biology. Perennial acrocarpous peat moss forming lax green or brownish tufts up to 25 cm high. Branches at stem tip in crowded groups forming a “head”. Branches along stem are in groups of 4–5: 2(3) spreading and 2–3 hanging. Stem leaves triangular, tongue-shaped, conspicuously cleft at the tip because of the resorbed cells. Spreading branch leaves slightly undulating when dry. Sporophyte spherical, raised above the “head”. Unisexual.
Habitats and populations. Plants grow in Sphagnum bogs, in marshes, along mountain streams and very wet habitats. Species prefers moderate nutrient-rich soils. Could be found as individual plants or mixed with other Sphagnum species.
Distribution in Bulgaria. Both species localities known in the country are in Rila Mts, in the Borovets locality, reported by different authors over different years. One of the localities is at 2000 m altitude along the path from Borovets to Musala peak.
General distribution. Balkan Peninsula (Bulgaria, Romania), boreal zone of Europe (abundant in N Scandinavia), Asia, North America. Boreal-montane species.
Threats. Desiccation, anthropogenic air and water pollution, tourism development. The species is characterized by low potential for sexual reproduction.
Conservation measures taken. One of the localities (that at 2000 m altitude) is within Rila National Park and in a site of the European ecological network Natura 2000 in Bulgaria.
Conservation measures needed. The localities in Bulgaria are in the southernmost part of the species distribution area. Long-term study is necessary, as well as assessment of the trends in habitat changes, prognosis for population development and based on this identification of appropriate conservation measures.
References. Podpéra 1911; Ganeva & Düll 1999.
Author: Anna Ganeva
