Desmid species
in the Netherlands

Desmids are unicellular micro-organisms belonging to the conjugatophycean green algal groups of Mesotaeniaceae and Desmidiaceae. They occur in standing freshwaters. Although among the microbes counting as real giants, with the unaided eye even the largest representatives are hardly to be seen.

So, for studying them a microscope is indispensable. Only under the microscope (magnification 40 to 400x) it appears how aesthetically appealing most of the species are. The bright-green cells show a remarkable symmetry. Actually, each cell consists of two half cells being mirror images of one another. Because most of the species prefer clear, nutrient-poor water bodies in vulnerable habitats, desmids lend themselves well for water quality and conservation management studies.

This website provides general information on the biology of desmids and each month, by means of photos, it discusses a selected species known from the Netherlands and Flemish Belgium. Furthermore, also the Dutch journal 'Desmidiologische Mededelingen' (Desmidiological Communications) can be consulted on this site.

Desmids of the Lowlands

Desmids of the Lowlands 2nd edition

Peter Coesel & Koos Meesters

Cosmarium quadratum
Desmid of the Month
July 2024

Cosamarium quadratum
Image © Alfred van Geest