Northwest Lichenologists

ID help Aspicilia sp.?

  • 06 Oct 2015 2:47 PM
    Message # 3564172

    Can’t key this (2 versions of same species) using my references. 

    specimen from Mt Townsend in the northeast corner of the Olympic Mts, WA

    on basalt 1890m elevation

    not sure how to describe the thallus - something like rosulate with lobulate margins?

    thallus K neg

    hymenium a70 and b80µm 

    exciple with crystals soluble in K

    spores average (within asci) 17x10µm

    paraphyses anastomose with moniliform apices


    photos posted to gallery:

    1 image 4cm across

    2 thallus "a" with many well developed apothecia, thallus is 11mm across

    3 closer view of "a"

    4 apo sxn "a" (600µm across) H2O polarized/unpolarized

    5 portion of apo sxn "a" KOH        

    6 thallus "b" with elongate somewhat radiating areoles protruding (bullate?) towards thallus center,18mm across

    7 closer view of "b"

    8 apo sxn "b" (450µm across) H2O polarized

    9 portion of apo sxn "b" KOH (shows anastomosing paraphyses)


    Last modified: 09 Oct 2015 6:13 PM | Richard Droker
  • 07 Oct 2015 7:42 AM
    Reply # 3565114 on 3564172
    Bruce McCune (Administrator)

    This is an Aspicilia, maybe A. candida. The lobate to fimbriate margins are typical for that, but the thallus of that is usually more continuous to rimose. It's a calciphile. Was this from calcareous rock?

    Last modified: 07 Oct 2015 7:43 AM | Bruce McCune (Administrator)
  • 10 Oct 2015 8:07 AM
    Reply # 3570877 on 3564172

    Thanks Bruce. A. candida fits. (CNALH documents 2 specimens from Deer Park, not far from Mt. Townsend.)


    The substrate appeared to be a dark, greenish, fine-grained basalt. Initially no reaction with acid, but got a vigorous reaction when some acid penetrated a crack. On breaking the specimen I find tiny veins of white calcite. (Eocene Crescent Fm is predominantly submarine basalt, but with some red foraminiferous limestone interbeds.) 


    Besides assuming non-calcareous substrate I was confused in that all the photographs of A. candida available (the best are Tim Wheeler’s) depict relatively continuous (although sometimes eroded) thalli which are very white. My specimen somewhat reminded me of something I had photographed but didn’t collect in Iceland - 2010-06-02 at 06-18-39 | Flickr - Photo Sharing!


    (Corrected my original message to the forum - hypothecium should have read hymenium)

  • 13 Oct 2015 12:14 PM
    Reply # 3575993 on 3564172
    Bruce McCune (Administrator)

    Great sleuthing on the rock, Richard. Most of the time we just miss subtleties in the rock like that.


    I think the phenomenon of calcite deposits out of basalt cracks/seepage is pretty interesting. Would be nice to know more about that, such as whether some kinds of basalt are more prone to that than others and how the geomorphic/climatic environment affects it.


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