a. Zoospores: They are seen in aquatic members. Zoospores are motile and develop into new plants. May be simple or may have 2 flagella. They are produced during favourable conditions.
b. Aplanospores: These are non motile spores reported in terrestrial organisms. They are thin walled, formed by the cleavage of protoplasts within a cell. They are also produced during favourable conditions.
c. Hypnospores: They are thick walled, non motile spores produced during unfavourable conditions.
d. Akinetes: they are perennating structures formed during unfavourable conditions. On the onset of favourable conditions, the entire cell wall will give rise to a new plant.
e. Tetraspores: In brown algae, certain cells from tetrasporangia produce non motile tetraspores. These are formed due to meiosis. So these germinate to develop into haploid plants though produced on a diploid plant.
f. Palmella stage: The zoospores, sometimes do not come out of the parent cell and get enclosed in a mucilaginous envelope. These cells divide and redivide to form the colony of daughter cells and is referred to as palmella stage. It is a temporary stage formed during favourable conditions.