Dinoflagellates have armour-plated cells with two long whip-like tails (flagella) that beat to move them through the water.
Gonyaulax – when large numbers become concentrated in one area, the sea looks like weak soup and is referred to as a ‘red tide’, although the colour varies according to the species involved. The Red Sea is so named because of the frequent appearance of red tides, and dinoflagellates may be the source of the biblical story about the Nile turning to blood.
JOHN ANGUS 