Surirella Guide
Credit: Elizabeth Ruck
  1. Frustules isopolar or heteropolar
  2. Raphe positioned along entire valve margin
  3. Raphe located within a canal, which may be raised above valve surface

Cells of Surirella grow as single, isolated cells. The frustules may be either isopolar or heteropolar. Like other genera within the family Surirellaceae, the raphe system is positioned along the margin of the valve. The raphe is located within a canal, which may be raised above the valve surface in some species. Cells may be highly silicified, with spines and silica nodules on the valve surface.

Species in Surirella are common in the benthos, especially epipelic habitats, across a wide range of water chemistry. Cells may be relatively small, to very large (a few hundred micrometers), depending on the species. Because of the extensive raphe system, species of Surirella have high motility as compared to other diatom genera. They are able to live within sand grains and fine sediment, and can move through the sediment by means of the raphe system.