3 Crustose for ID Help Please

[Lancashire Lad]

All found yesterday on drystone walls -Ingleton (Limestone) Area.


A Xanthoria and a Caloplaca ?


Very sulphurous yellow.
Possibly Psilolechia psora - (Probably way out with this)?


No idea at all on this

Any ID help/suggestions much appreciated.

Regards
Mike.

[JennyS]

Hi Mike, but not sure how much help I'll be .....

1. Lichen on left looks (very, very tentatively) like Xanthoria ectaneoides and RH one possibly Caloplaca saxicola, though I wouldn't be surprised to be wrong on both

2. LH photo is a Rhizocarpon - probably R. geographicum

3. Not a clue - and I've a few photos of something very similar myself ......

[AlanS]

Hi Mike,

1. Yes, a Xanthoria and, like Jenny, I think it might be X. ectaneoides. Usually this is coastal but it does also occur inland on limestone and the strap-shaped lobes have the right look.

The Caloplaca is C. flavescens I feel reasonably sure. It is not looking at all at its best though, and maybe is being attacked by something?


2. I think both photographs are Rhizocarpon geographicum, the right hand photo showing a less fertile state.


3. Yes I do know this. Currently a pretty rubbish photograph on my site, but soon (?) to be replaced by a much better one (i.e. in focus!). It is Belonia nidarosiensis. Forms a cracked, orange, powdery crust, frequent on limestone and (according to Dobson) mortared church walls.
Like me it doesn't like direct sunlight, which is why I am trying to stay indoors until this dreadful weather ends.

Alan

[Lancashire Lad]

Thanks to you both, JennyS and AlanS.

I did think that the sulphur coloured Rhizocarpon geographicum ones might both be the same type, as there was just one small area of wall with about 10 specimens all within about 3 metres. I didn't see anything similar elsewhere. I was quite taken by how spectacular the colour looked in the sunshine.

The Belonia nidarosiensis was tucked away at the very bottom of a dry stone wall in an area that would receive little direct sunlight. I only saw that one specimen, and am very pleased to get an ID, since the photo, (even though it was the best I could get), is pretty dire.

Regards
Mike.

[AlanS]

Originally Posted by AlanS

1. Yes, a Xanthoria and, like Jenny, I think it might be X. ectaneoides. Usually this is coastal but it does also occur inland on limestone and the strap-shaped lobes have the right look.

Looking at this again and comparing it with a few photographs of my own, I think this has to be just Xanthoria parietina, even though X. ectaneoides is said to occur inland on limestone.

The two species are very difficult to separate at times. Many have considered them to be one and the same but I think that there have been DNA studies supporting their difference, and when good populations of both grow in proximity there are convincingly two entities present, but individual thalli are often puzzling.
Anyhow, looking at the shape of the thallus lobes again, the colour scheme, and remembering that X. ectaneoides usually fruits quite sparsely or not at all, I have to change my vote. Sorry.

Alan