Abstract
Terpsinoë Americana is a widely distributed diatom of oceans in the subtropical and tropical zone and occurs in both brackish and marine waters. Its occurrence as a living component of diatom communities is mostly limited to the coastal areas of oceans (for a review see Alhonen et at. 1984, Foged 1975, Laws 1988). Living T. americana has rarely been recorded from Europe (e.g. König 1959) and the occurrence closest to the Baltic Sea is the North Sea coast of Germany (Brockmann 1950).