Pyramimonas gelidicola sp. nov. (Prasinophyceae), a new species isolated from Antarctic sea ice

Abstract
A prasinophycean flagellate blooming in Antarctic sea ice is reported for the first time. Pyramimonas gelidicola sp. nov., isolated from Prydz Bay, East Antarctica, is described from the light and electron microscope with particular emphasis on the fine structure of the periplast scales. Diagnostic features are details of the scales, including a new type not previously seen in the genus, a ring of lipid bodies in the collar surrounding the pit, cell size and shape. Ability for growth in vitro over a broad range of culture conditions is discussed in relation to the Antarctic sea ice environment.