s A Field Guide to the British Seaweeds - NMBAQC

Audouinella sp.
Other Audouinella species tend to be much smaller and only a few cells in length and require a
microscope just to locate them. They grow epiphytically on a variety of other algal species e.g. A.
davesii is commonly found on the fronds of Palmaria palmata but may also be found within hydroids
and can live throughout the littoral. The cell size and shape may vary as can the chloroplast but it rarely
fills the whole cell as with A. purpurea. Plants tend to be short and variously branched growing from
either a unicellular or multicellular base. Plants can also be erect, prostrate or a combination of the two.
They can be differentiated from A. purpurea by their microscopic size.
Audouinella davesii found growing
on the frond of Enteromorpha sp.
A number of Audouinella
sp. are often found in
hydroids
Audouinella sp. showing unbranched form growing
from a multicellular base and highly branched form.