Ecology and morphology of the freshwater red alga Chroothece in the British Isles
Pentecost, Allan; Whitton, Brian A.; Carter, Christopher F.
The ecology of Chroothece at six sites in the UK and one in the Isle of Man is described, together with morphological observations. Sites were near vertical or steep, wetted by trickles and drips, but subject to marked changes in extent of wetting and with parts of the general area liable to desiccation. Water chemical data are given for four sites, where the alga occurred in base-rich, low nutrient waters and with filterable organic phosphorus the principal fraction of total filterable orthophosphate. Chroothece was associated with a range of cyanobacteria, especially species of Schizothrix, but also colonial, heterocystous and presumed nitrogenfi xing genera, and calcicolous diatoms (e.g. Epithemia and Mastogloia). Morphological measurements suggest the Chroothece populations all fit C. richteriana.