Distribution and habitat
Dry river jelly lichen
Distribution
This is a northern temperate species, which is known from:
- Karelia, Scandinavia
- Central Europe
- British Isles
- North America
In Central Europe most of its populations are restricted to cool upland areas, whereas in northern and western parts of its European distribution range it also occurs at low elevations.
Habitat
Unlike most other lichens, this species is a freshwater organism and needs frequent inundation. It can even grow in permanently submersed habitats, where only a small percentage of other lichens occur.
The River Jelly Lichen needs cold and clear running water, but avoids strong currents where its delicate thallus could be damaged.
It generally grows on siliceous rocks (most often hard sandstones in the UK) and develops best under moderate shade from deciduous trees on the stream banks.