A Revised Check-List of British Marine Diatoms

Abstract

The preliminary check-list of British marine diatoms first appeared in this Journal about 20 years ago (Hendey, 1954), and since that time many advances have been made in the study of these organisms. First, the known flora has been extended very considerably (Hendey, 1964, 1973) and much has been added to our knowledge of the structure of the valve by the use of the scanning electron microscope through the work of Hasle (1964, 1965a, b, 1972) and that of Ross & Sims (1970, 1971). This new information must inevitably lead to a reappraisal of views held on phylogeny within the group and consequently upon its systematic classification. While it would be premature at this stage to over-emphasize the importance of information gained in this way until a wider range of species has been examined, sufficient exists to support some minor changes and prepares the way for more radical changes that the new developments suggest. It should be pointed out, of course, that most of the ‘new information’ should more correctly be interpreted as confirmation of earlier views based solely on structure as seen in the light microscope of classical design and that some of the changes made in the classification as a result of these had been made many years previously, but the scanning electron microscope has enabled us to see more clearly the ultimate structure of the siliceous frustule of the diatom, thus permitting more positive decisions to be made regarding relationships and possible lines of descent.At the First Symposium on Recent and Fossil Marine Diatoms held at Bremerhaven in 1970, Simonsen (1972) put forward some ideas for a more natural system of classification of the centric diatoms.