Chrysochromulina leadbeateri

C. leadbeateri has caused fish kills in Northern Norway, it produces Ichthyotoxins, which can form deadly complexes with polyamines (Johnsen 1999).

Several scale morphotypes exist, in both types of scales. Implications for the species concept in C. leadbeateri

C. leadbeateri is widely distributed.

The cells are circular in outline. The flagella and haptonema are considerably longer than cell, but the haptonema is often coiled up. The cell surfaces are covered by two distinct types of scales, an outer layer of morphologically simple scales and an inner more complex layer.

Cells are roughly spherical with long flagella and haptonema. The haptonema is usually coiled up. All appendages are inserted anteriorly. Cells contain two golden-brown chloroplasts with a pyrenoid each. Cells possess two types of scales covering the cell surface. Both are circular in shape and have a cruciate structure at their centre. One has a simple morphology, with little ornamentation, but a low upright rim. The second scale type is more complex with the scale surface divided by three concentric rings. The innermost ring surrounds the central structure. The outer two rings contain a series of radiating ribs.