Description: A major part of the diatom names we use nowadays are based on research performed in and descriptions made in the nineteenth century by famous diatom scientists such as Kützing, Grunow, Van Heurck and Smith. Most of their material that formed the base for this pioneer research is kept in major herbaria and museums around the world. In many cases, the original authors added short written descriptions and, in some cases, also often tiny line drawings. These descriptions and drawings were later interpreted and used by later authors, sometimes drifting away from the original idea the nineteenth century authors had. As every species also represents its own ecological preferences, it is clear that a good ecological analysis based on diatom species can only be achieved when the original taxonomic identity of that species is correct. In this presentation, several examples are discussed of renewed taxonomic research of some well-known species and what consequence the new insights may have on ecological work. In some cases, the updated ideas had no major impact but examples resulting in a clear ecological shift will also be discussed.

Target Audience: This presentation will be directed at participants with an interest in diatom taxonomy but also ecology. Both beginners and experienced diatomist will probably find some useful information in it how to deal with and solve taxonomic problems.