More Scilly Lichens

[Tiggrx]

Here a few more lichens for ID please. All were photographed on coastal rocks in Scilly (the first was actually on the stone wall of a coastal cowshed).

I think they are all species of Usnea but am having difficulty getting any closer than that.








thanks for any help

[JennyS]

Hi Aaron,
You really need a shot of the base for Usnea's - whether or not its blackened helps to narrow down the ID possibilities a bit......

The second one is a Ramalina rather than an Usnea - its probably Ramalina siliquosa, though I haven't a clue what additional species are to be found in the Scillies

[Tiggrx]

Originally Posted by JennyS

You really need a shot of the base for Usnea's - whether or not its blackened helps to narrow down the ID possibilities a bit......

Oh well, that's a good excuse to go back

Originally Posted by JennyS

The second one is a Ramalina rather than an Usnea - its probably Ramalina siliquosa, though I haven't a clue what additional species are to be found in the Scillies

Well I thought I had R. siliquosa sorted! This looks more branched/feathery to me, but I expect you are right

Thanks for the comments

[JennyS]

Well I thought I had R. siliquosa sorted! This looks more branched/feathery to me, but I expect you are right

I don't.....!

Ramalina subfarinacea is another possibilty, but its not one I've come across myself. Link below is to a photo of R. subfarinacea from British Lichens

http://www.britishlichens.co.uk/spec...ea%20large.jpg

[AlanS]

Usnea is a highly critical genus in which minute examination of the isidia/soredia and junctions of the branches is essential. There are good diagrams in 'Dobson'.
Overall appearance of the species is very variable, so identifications without examination of these characters are not identifications at all, but just guesses.

So the only photograph I'll comment on is no. 2, in which I agree with Jenny's first thought: Ramalina siliquosa in one of its many guises. I don't think it is R. subfarinacea (cannot see the characteristic soralia at the tips of the fronds), and it looks like there are some apothecia present, which R. subfarinacea seems not to have.

Alan

[Tiggrx]

Thanks Alan,

I'll be content with Usnea sp.

Ramalina siliquosa must be more variable than I thought. I shall look through some of my remaining unnamed pics to see if any of the others come within its range of variation