Calliergon giganteum
Calliergon giganteum (Schimp.) Kindb.
Campyliaceae
Conservation status. Endangered [EN B2ab(iii)].
Morphology and biology. Robust, perennial, pleurocarpous moss forming yellowish green to green tufts. Shoots prostrate or ascending, up to 20 cm long, densely pinnately branched, with cuspidate tips. Leaves spreading, large, broad ovoid to oval triangular, apex rounded. Nerve single ending below apex, yellowish, brown in older leaves. Unisexual, rarely with sporophytes, in Bulgaria collected only as sterile plants.
Habitats and populations. Grows in swampy depressions or submerged in fens and along streams. Moderately minerotrophic. The populations have restricted distribution and good density, but restricted reproductive potential.
Distribution in Bulgaria. Rila Mts (locality of Kurtovo and below Musala peak), Rhodopi Mts (Western – by Batak dam).
General distribution. Balkan Peninsula, W, C and N Europe, NE, E and C Asia, North America. Northern sub-oceanic species.
Threats. Major negative factor is habitat degradation due to drainage and water logging under reservoirs of wetlands. Upon drainage the overgrowth by competitive higher plants is favoured. The locations in the Rhodopi and Rila Mts (locality of Kourtovo) are subjected to mowing and grazing, which cause additional degradation of the habitat.
Conservation measures taken. The population below Mousala peak is within the Rila National Park and in a site of the European ecological network Natura 2000 in Bulgaria.
Conservation measures needed. To study the dynamics of numbers and area of the populations, as well as the biology and ecology of the species in Bulgaria, to elucidate the threatening factors and monitor the populations. To establish a protected area at the locality of Valchi Polyani (Kurtovo) in Rila Mts.
References. Petrov 1963; Ganeva & Düll 1999; Gyosheva & Ganeva 2004.
Author: Rayna Natcheva
