Observation 162805: Xanthoparmelia (Vain.) Hale
When: 2014-04-04
No herbarium specimen

Notes: On north facing rock at about 5200’ elevation in pinyon pine habitat. Foliose lichen up to 6 cm. in dia. Upper surface yellow-green, somewhat wrinkled, w/o ididia and soredia. Lower surface medium brown. Apothecia non-stipate, dark brown discs with smooth margins and up to 3 mm wide. Medulla yellow then orange with 5% KOH.


Forgot my camera so took these home to test and photograph—inside shots make thallus appear less yellow green than it actually was
Medium brown lower surface and orange medulla after application of KOH

Proposed Names

57% (1)
Eye3 Eyes3
Recognized by sight
28% (1)
Based on chemical features: KOH on medulla yellow then orange

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Eye3 = Observer’s choice
Eyes3 = Current consensus


Add Comment
Thanks, Chris.
By: Terri Clements/Donna Fulton (pinonbistro)
2014-04-09 19:37:11 PDT (-0700)

We’re always on the look out—the lack of rain has made us aware of all of the wonderful things that grow despite the arid climate. It’s a another world!! Hopefully we’ll get some rain before we head east the end of May. We’re looking forward to an AMC foray this Spring so we can meet fellow members and see what our great state has to offer when there’s enough precip! Let’s do a rain dance.


Very impressive
By: Chris May (ccmaymd)
2014-04-09 18:46:57 PDT (-0700)

Learning a lot about obscure Arizona species from seeing your collections. You are becoming real experts.

Commendable dilligence!
By: Jason Hollinger (jason)
2014-04-06 08:20:54 PDT (-0700)

Great analysis. Chemistry of these things is tricky. But you can play the odds pretty safely in absence of TLC verification. If you ever take the dive and get a microscope, please consider taking the Eagle Hill course in Maine. Brodo used to (still does?) teach it every year. Supposed to be excellent. Great way to get an big jump start on that super-steep learning curve.

Thanks, Jason
By: Terri Clements/Donna Fulton (pinonbistro)
2014-04-05 13:15:17 PDT (-0700)

I’m trying to learn about lichens and do a better job of documenting them. I used the ASU macrolichen key to get to genus and then looked at CNALH descriptions for each of 14 species known to occur at this elevation in Arizona. I was able to rule out some by presence of isidia, size of thallus and discs, and/or spot tests as some were either K- or K+ but red on the medulla. All of the species with K+ reaction has some amount of norstictic acid in the medulla and it is a major component in X. californica (" medulla with norstictic acid (major) and connorstictic and ±hyposalazinic acids (minor or trace"). X. californica was the only one of the non-isidiated species to have a K+ yellow to orange reaction. I know this isn’t conclusive as there may be other species I haven’t considered. One of these days I would love to get a microscope—and learn how to use it!! Thanks for the help and encouragement.

Nice observation!
By: Jason Hollinger (jason)
2014-04-05 11:08:08 PDT (-0700)

I would read K+ yellow turning orange as either stictic acid aggregate with possibly some small amount of norstictic acid mixed in, or weak norstictic acid alone. I don’t have my Sonoran Flora handy. Would the presence or absence of norstictic acid make a difference in the key? If so, you may be able to verify the state by applying a wash of KOH to a small section of the thallus under compound microscope. Norstictic acid, even in low quantities will produce distinctive needle-shaped crystals in 10% KOH at 400×. (Be sure to wait for a few minutes; low concentrations of norstictic acid sometimes take a long time to produce crystals.)

Created: 2014-04-04 15:18:01 PDT (-0700)
Last modified: 2014-04-04 15:24:41 PDT (-0700)
Viewed: 67 times, last viewed: 2016-10-25 06:15:58 PDT (-0700)
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