Investigators of freshwater ecosystems inevitably are faced with various microphytes. It is generally accepted that algal species (among which phytoplankters) are important indicators of water quality. In particular, desmids (a group of green algae) are excellent indicators of environmental conditions such as pH, conductivity and trophic state of a water body.
In addition to that, because of their preferential occurrence in vulnerable habitats, desmids lend themselves well to figuring in conservation studies. It goes without saying that using desmid species to that end is only justified in the case of a reliable identification.
The present flora (2nd revised and extended edition) aims to represent all desmid taxa known from the Netherlands and adjacent lowland areas. Some 640 species and more than 150 additional varieties are dealt with and depicted. Because of the predominantly cosmopolitan nature of most species, the present flora may also be of use outside the above-mentioned geographical region.