s A Field Guide to the British Seaweeds - NMBAQC

Ceramium nodulosum
This is a highly branched filamentous species, often
characterised by its banded or striped appearance which may
be visible with the naked eye. Although the main axis consists
of a single row of cells there is a covering of small cells which
become particularly dense at the junction between axial cells,
which results in the banding. The branching pattern is usually
dichotomous or subdichotomous where terminal branches
may be tightly in-rolled. Fine hairs may also be present along
the full length of the filament but these are not to be confused
with spines. Although there is a number of Ceramium spp.
this is the most common and can be found throughout the
littoral within rockpools, on open rock surfaces and growing
epiphytically on a range of red and brown species. The form
can be quite variable.
Single row of axial cells
Dense covering of small cells
between axial cells and
strongly in-rolled apices
Highly and dichotomously
branched
C. nodulosum filament with
fruiting bodies and obvious
banding