Three Crustose Lichens

[chrisjohnson]

Hi Folks

There seems to be an abundance of superficially similar crustose lichens with black apothecia, and I'm not making much progress. Any help pointing me in the right directions would be appreciated. They were all on granite at a coastal site.

Lichen 01 was in a very exposed site. Thallus with a shade of apple-green, prothallus white, apothecia domed.

Lichen 02 has a similar thallus to 01 but with a black prothallus and the apothecia are semi-domed.

Lichen 05 has a white 'crazed' thallus and a black prothallus. The apothecia are flat-topped. I thought the rusty-red colour was another lichen but as it was confined to this lichen, I now wonder if it's fungal?

Thank you for looking,

Chris

[JennyS]

Hi Chris,

The first step with many/most crustose species is chemical tests (and even then you often need a microscope for spore details etc): The British Lichen Society - Chemicals for Lichen Identification

This lot have a Lecidea / Porpidea look to them - argh!!!!
The rusty colour in the last is likely to be caused by iron oxides in the rock but the smaller black and white jobbie to the left of the main image could be a Buelllia - you need to know the K reaction to differentiate between Buellia aethalea and B. stellata.

Sorry not to be much help but I'm struggling myself with dots on rocks!

[diggleken]

Hi Chris and Jenny,
I am at wits end with these too.........porpidia macrocarpa crustulata cinereoatra is my favoured description!
But if I may hijack a little Chris - is this Candelelariella aurella?ttp://www.wildaboutbritain.co.uk/archive/showphoto.php?photo=183472][/url]
Cheers
Ken

[synangium]

Hi lichenophiles,

I'm ignoring dots on rocks until I've conquered the 'easier' species.

You could be right Ken, but you might want to consider Candelariella vitellina too.

Nigel

[chrisjohnson]

Originally Posted by JennyS

Hi Chris,

The first step with many/most crustose species is chemical tests (and even then you often need a microscope for spore details etc): The British Lichen Society - Chemicals for Lichen Identification

This lot have a Lecidea / Porpidea look to them - argh!!!!
The rusty colour in the last is likely to be caused by iron oxides in the rock but the smaller black and white jobbie to the left of the main image could be a Buelllia - you need to know the K reaction to differentiate between Buellia aethalea and B. stellata.

Sorry not to be much help but I'm struggling myself with dots on rocks!

There is something perversely satifying Jenny, to know you are also struggling with dots on rocks, if you'll forgive the black humour!

I have K & P which I use at home but it's not always easy taking samples off granite. I must takes some out with me especially as we have an awful lot of granite but little in the way of trees.

Thank you for the guidance.

Chris

[chrisjohnson]

Hi Ken

You are more than welcome to highjack by black dots. I think Nigel has the best idea.

Chris

[JennyS]

I'm ignoring dots on rocks until I've conquered the 'easier' species.

That was my philosophy too so I went mothing and leaf-mining instead - trouble is now it's winter and I'm back to the dots ........

I take dropper bottles of K and C with me to test in situ and a kitchen knife to scrape aps off if I can't get a chunk of rock but I don't feel like I'm making a lot of progress so far!

[diggleken]

Originally Posted by synangium

Hi lichenophiles,

I'm ignoring dots on rocks until I've conquered the 'easier' species.

You could be right Ken, but you might want to consider Candelariella vitellina too .

Nigel

Yes, quite right Nigel - I think there's a sort of blackish prothallus showing, so thats where I got to with C aurella.
I'll look more carefully next time.
Back to the black dots............mmmhhhhh!
Cheers
Ken

[chrisjohnson]

Originally Posted by JennyS

That was my philosophy too so I went mothing and leaf-mining instead - trouble is now it's winter and I'm back to the dots ........

I take dropper bottles of K and C with me to test in situ and a kitchen knife to scrape aps off if I can't get a chunk of rock but I don't feel like I'm making a lot of progress so far!

I started with moths and turned to fungi, mainly resupinates, for the winter. Lichens is a natural progression but it's bedlam in the overlap periods.

Chris