Porella pinnata
Porella pinnata Linnaeus
Porellaceae
Conservation status. Critically Endangered [CR B2ab(iii)].
Morphology and biology. Perennial, leafy liverwort forming large dark green mats. Shoots prostrate, to 10 cm long, irregularly branched, with lingulate amphigastria as wide as the stem. Leaves situated in one plane, divided into two overlapping lobes of unequal size. The upper leaf lobe is larger, broadly elliptical, entire, flat; the lower is smaller, narrower than the stem, lingulate. Unisexual. In Europe only female plants have been recorded.
Habitats and populations. Grows on damp to wet rocks and at the bases of trees along river banks, along streams and waterfalls, sometimes submerged, in beech and coniferous forests. The populations have restricted distribution and low density.
Distribution in Bulgaria. Rila Mts (around the Kostenetski waterfall).
General distribution. Balkan Peninsula (Bulgaria), W Europe, N Africa, North America. Southern oceanic species.
Threats. The species is sensitive to water pollution and river drying due to the changes in water regime and aridisation of climate. The locality at Kostenets village is frequently visited by tourists.
Conservation measures taken. The population near Kostenets village is within Chavcha Nature Monument.
Conservation measures needed. To study the dynamics of the numbers and areas of the populations, as well as the biology and ecology of the species in Bulgaria; to elucidate the threatening factors and monitor the populations.
References. Petkoff 1908.
Author: Rayna Natcheva
