Northwest Lichenologists

help with Caloplaca

  • 12 Feb 2017 3:28 PM
    Message # 4605835

    Having trouble keying Caloplaca growing on the creases between the scaly leaves of western red cedar - see photos.

    Isolated apothecia ≤0.4mm diameter. Disk K+purple. Hymenium about 65µm. Hypothecium about 115µm. 8 spores/ascus. Average about 15x9, septum about 9µm. Paraphyses about 1.5µm diameter with apices hardly swollen. Not sure if bits of leprose thallus (K neg) also growing in the creases is related.


    (I began with the apothecial sections in water on a slide, pulled through KOH, then pulled through water before heating with a lighter. Please let me know if this was not correct.)

    Last modified: 12 Feb 2017 4:41 PM | Richard Droker
  • 13 Feb 2017 8:37 AM
    Reply # 4606880 on 4605835
    Bruce McCune (Administrator)

    The broad septum and broad spores suggest Caloplaca pyracea, but the thallus is unusual for that -- perhaps because the substrate is unusual?


    Btw, if I treat with K I don't bother with heat treatment, since the K clarifies the septum structure anyway (as your photos show nicely). The only time I use the heat treatment is when the material is fresh and the spore structure tends to be obscured by oil droplets and I don't want to put K on it.



  • 13 Feb 2017 8:39 AM
    Reply # 4606897 on 4605835
    Bruce McCune (Administrator)

    Btw #2: The Lecanora sharing space with the Caloplaca looks like L. pacifica with its murky greenish disk.


  • 13 Feb 2017 12:56 PM
    Reply # 4607284 on 4605835

    Thanks Bruce. The apothecia seem consistant with C. pyracea.


    Regarding unusual substrates, they always intrigue me, but probably my time would be better spent on all the common lichens to be learned.


    Lecanora pacifica also seems consistant with my specimen, although my spores are too small, averaging about 8x5µm. (Nice to have your "crust tour" photos to compare.)


    I'm partially colorblind and would have called the discs caucasian flesh color, but the ones just uploaded do look murky greenish to me.

    Last modified: 13 Feb 2017 12:58 PM | Richard Droker
  • 02 Mar 2017 2:55 PM
    Reply # 4644380 on 4605835

    Now having different search image realize C. pyracea extremely common. Posted some photos on bigleaf maple twig.

    Last modified: 02 Mar 2017 2:57 PM | Richard Droker

© Northwest Lichenologists

NWL Privacy Policy

Powered by Wild Apricot Membership Software