There is not much limestone in the North Cascades. I find it interesting that this lichen occurs in a relatively small and isolated outcrop.
According to Thompson (1997). American Arctic Lichens, “The distinction between this [P. Calva] and P. rupestris is very poor, as the gradations of amount of thallus seem to blend in many cases…in addition they appear to occur together in some localities. When the apothecia are immersed in the limestone substratum in pits, the lichens are known as Protoblastenia incrustans (DC.) Steiner. But this character also appears to intergrade.”
Also used a key (Kainz and Rambold?) which now I can’t open, sent to me by Bruce McCune. Our exchange included:
me – The first photo (damp) is from a marble layer at 1860m in the Napeequa Schist in the North Cascades. In C.W. Smith et al. it keys out for me to Protoblastenia incrustans for me. The surface is soft in places, but seems to be a mass of calcite crystals with algae and fungal cells. There are 3 specimens labeled as P. rupestris in the UW Herbarium. One, from northern AK, looks like this one. Another from northern AK has sessile apothecia. The third, from Colorado, looks sort of in between, and is identified as P. rupestris v. incrustans. As I am not finding many records of P. incrustans, perhaps this is of interest.
Bruce – Your inquiry about Protoblastenia incrustans prompted me to assemble what I have on that. Please see the attached key. I also looked through my specimens and I don’t have either P. incrustans or P. calva.
|I’d Call It That||3.0||4.84||1||(wanderflechten)|
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Created: 2012-01-25 10:27:30 PST (-0800)
Last modified: 2012-01-25 10:31:16 PST (-0800)
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