Distribution in scandinavian waters
|Maximum diametre: 0,8 mm. Compare
with the size of a hair.
Appearance: Living halosphaera is spherical and has a thick cell wall, but light yellow to dark green patches are visible through it.
Depth: Halosphaera is most common in the upper depths that receive sunlight.
Misc: Halosphaera changes between two different forms: a large spherical immobile form as pictured above and a smaller swimming form, with four flexible protrusions (flagellae). The smaller mobile halosphaera form in large numbers within the immobile halosphaera and look like grains or patches as pictured above. Halosphaera is also found in colder maritime areas. During the spring and early summer large numbers can drift together on the water surface and cause the surface to be oily and green.
Classification: Halosphaera are members of the green alga group. There are four specie within this genus (Halosphaera); in the picture above, Halosphaera parkeae is seen together with another green alga (Pterosperma nationalis), that appears to have two black patches.