Search found 78 matches

by Mark Powell
Tue Mar 02, 2021 5:13 am
Forum: Lichens
Topic: Shetland Lichens. A journey...
Replies: 31
Views: 1210

Re: Shetland Lichens. A journey...

I suspect that your putative X. conspersa is something different but there is no shame at all in your suggestion. Your lichen has a rather bluish grey colour and, when looked at close up, it has rather conspicuous maculae. These features put me in mind of Physcia caesia . Screenshot 2021-03-02 at 4....
by Mark Powell
Tue Mar 02, 2021 5:02 am
Forum: Lichens
Topic: Shetland Lichens. A journey...
Replies: 31
Views: 1210

Re: Shetland Lichens. A journey...

If I encountered your latest Caloplaca when surveying an inland churchyard I would assume it was C. flavescens on sight. A complication arises when recording near the coast in distinguishing C. flavescens from the supposedly very similar C. thallincola . In case you don't have access to LGBI2 (the 2...
by Mark Powell
Mon Mar 01, 2021 3:58 pm
Forum: Lichens
Topic: Physcia tribacioides?
Replies: 0
Views: 61

Physcia tribacioides?

We have received a query on twitter. This lichen, said to be about 1.5 cm diameter, was found on a cherry tree in a car park in Surrey. trib12.jpeg I asked the poster whether he was able to get a photo of it when not soaking wet and he promptly returned and sent this: trib11.jpeg I have a fairly str...
by Mark Powell
Mon Mar 01, 2021 11:38 am
Forum: Lichens
Topic: Athallia from Aarhus, Denmark
Replies: 7
Views: 997

Re: Athallia from Aarhus, Denmark

Although the younger apothecia in your photo are rather yellowish for pyracea , I am placing more weight on the morphology. The apothecia in various individual Athallia species can be rather variable in colour. In the following close-up from your photo, we can see rather scattered (not closely packe...
by Mark Powell
Sun Feb 28, 2021 8:36 pm
Forum: Lichens
Topic: Athallia from Aarhus, Denmark
Replies: 7
Views: 997

Re: Athallia from Aarhus, Denmark

It is nearly a year since this query about Athallia was posted. Forgive me if I revert to ' Caloplaca ' for the purposes of this post. The apothecia are not quite as closely packed and even-sized as I would expect in C. holocarpa or C. cerinelloides . In addition there appears to be a thalline margi...
by Mark Powell
Sun Feb 28, 2021 8:18 pm
Forum: Lichens
Topic: Pale morph of Lecidella elaeochroma?
Replies: 2
Views: 60

Re: Pale morph of Lecidella elaeochroma?

I feel sure that you have a pale morph of Lecidella elaeochroma , pale because it lacks one of the two normal pigments (lacking the blue-green pigment). In addition to the characters that you have mentioned (ascus type, simple ellipsoid ascospores, C and UV+ orange reactions) I can see numerous minu...
by Mark Powell
Mon Feb 22, 2021 1:09 pm
Forum: Lichens
Topic: Thelidium woes
Replies: 2
Views: 78

Re: Thelidium woes

I can't provide you with any confirmed identification, just a bit of discussion. First, more for others' sake than yours, I presume you satisfied yourself that it belonged to Verrucariaceae and hence was a Thelidium ? It certainly looks right and the absence of paraphyses would provide good reassura...
by Mark Powell
Thu Feb 04, 2021 9:48 pm
Forum: Lichens
Topic: Candelariella aurella?
Replies: 2
Views: 96

Re: Candelariella aurella?

I think this one is easily dealt with. I am happy to confirm your lichen as Candelariella aurella . Your close-up photo of it is very characteristic with little or no yellow thallus present (in some specimens there are sparse small yellow blobs), bright lemon yellow apothecial margins and discs with...
by Mark Powell
Wed Feb 03, 2021 7:16 pm
Forum: Lichens
Topic: A Lecanora?
Replies: 5
Views: 347

Re: A Lecanora?

The draft keys to lichenicolous fungi that most people use when attempting to identify them is available online: http://www.ascofrance.fr/uploads/forum_file/LichenKeys2010-0001.pdf I am offering this in case you want to have a go but the keys are not for the faint-hearted and it has to be realised t...
by Mark Powell
Wed Feb 03, 2021 7:05 pm
Forum: Lichens
Topic: A Lecanora?
Replies: 5
Views: 347

Re: A Lecanora?

The new micrographs of the interior of the black dots do not belong to a dematiaceous hyphomycete! (I think the original micrograph now removed did show a fungus with brown walled vegetative hyphae). The one shown now is a different type of lichenicolous fungus with brown, septate (perhaps submurifo...
by Mark Powell
Wed Feb 03, 2021 5:37 pm
Forum: Lichens
Topic: A Lecanora?
Replies: 5
Views: 347

Re: A Lecanora?

You haven't started with the easiest type of lichen by any means but since it is growing in your garden it is understandable and sensible that you will be curious to study it. I am almost certain that this is Lecanora albescens . The trouble is that this belongs to a group of lichens which are parti...
by Mark Powell
Wed Feb 03, 2021 12:27 pm
Forum: Lichens
Topic: Parmelioid lichen for ID
Replies: 3
Views: 239

Re: Parmelioid lichen for ID

I'm afraid that I am not going to provide a definite identification but I will perhaps be able to help guide you in further examination of the specimen. Even when I expanded your photo as far as it would go, I can't clearly see the detail that I would require. Also, I suspect that you have two folio...