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Proposed Names

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Extraordinary claims require extraordinary proof
By: Jason Hollinger (jason)
2016-03-20 15:28:10 CDT (-0400)

There is no question this is one of the “physcioids”. The only options are Physcia, Physconia, Phaeophyscia, Physciella, Anaptychia.

Anaptychia: Easy to rule out: fertile with no soredia means A. ulotrichoides but that is only on rock.

Physciella: Also easy to rule out since there are no species without soredia in North America.

Phaeophyscia: Your specimen clear has no soredia, isidia or phyllidia. Rule out P. constipata since it looks nothing like it at all. And rule out P. decolor since it is only on rock and has distinctly brownish tint to it. That leaves P. sonorae, P. ciliata and P. endococcinodes none of which are known to occur in California.

Physconia: Only P. americana and P. californica regularly have apothecia, but both are lobulate to varying degrees, especially the rims of the apothecia.

Physcia: This is your only other option. I’ve seen P. biziana look like this before when growing on rocks strongly exposed to the sun. That’s why I suggest it.

So either we accept Physcia or we need to furnish some better proof than mere photos before we can accept a report of anything else from that area on that substrate.

A photo of the underside would go a long way. K test on the cortex would also be very helpful. You don’t happen to have a specimen, do you? :(

Another specimen
By: James Bailey (Silversea_Starsong)
2016-03-20 15:14:04 CDT (-0400)

all on this tree were similar, I added a second image for a nearby specimen. Other nearby oaks had Physcia looking lichens, maybe same one.

Strange specimen
By: Jason Hollinger (jason)
2016-03-20 15:04:56 CDT (-0400)

It looks most like a Phaeophyscia, in which case it would key out to P. ciliata, but that should be nowhere near that location.

That means it must be a really sunburnt Physcia(?) I would have to guess P. biziana. But with something that atypical, I would verify with chemistry and cortical anatomy. :(