Bright pink seaweed; could be a sea fern.
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I think this MIGHT be a little too bright for Comb Weed.
See mine http://www.ispotnature.org/node/376096
where the top two pictures are doubtful and may be replaced soon.
Obviously a closer view is necessary.
It is interesting that this has not yet been identified, as it is always being washed up on the beach after choppy seas.
Robert, do not despair. It is a very interesting group but needs close-to view to be more positive.
A x10 eye-glass resolves enough detail to get the group right.
I was not casting too much doubt really, I have enough of that with mine - which have too MANY close ups!
Rosie is quite possibly right but it cannot be guessed from the colour nor, necessarily, the flatness of the stem - I have found!
Looking at the original of yours, it may show that it has 'branchlets' coming off both sides of 'branches' - that might rule out Comb Weed. But I am discovering that it can be variable.
As you say it is a common colour and structure - so collect some more and take some pictures THROUGH a x10 hand lens - always worth an experiment.
OK Derek, It makes sense for me to bring a sample back next time I found some and I can use my macro on a tripod and that should do the trick.
That would be good. I would be very interested to know which species it is.
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