Centric
Minidiscus
- Cells very small (<5 µm)
- Single rimoportula near valve center
- At least one central or subcentral fultoportulae
- Internal rimoportula opening is a sessile, ellipsoid, labiate ring
Minidiscus is a common planktonic, centric, diatom genus in estuarine and oceanic waters. It is rarely reported, however, as cells are very small (mostly less than 5 µm, but up to 10 µm in diameter) and difficult, often impossible, to identify by light microscopy. Live cells are observed solitarily, in mucilaginous aggregations, or in...