Observation 66444: Phaeophyscia ciliata (Hoffm.) Moberg

When: 2009-06-21

Collection location: Madison, Wisconsin, USA [Click for map]

Who: Andrew Khitsun (Andrew)

No specimen available



Proposed Names

18% (2)
Recognized by sight
84% (1)
Recognized by sight: K- cortex, medulla, black corticate lower surface with lots of tiny rhizines, no soredia, closely appressed, very small lobes
Based on chemical features

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Eye3 = Observer’s choice
Eyes3 = Current consensus


Add Comment
Sounds like it
By: Jason Hollinger (jason)
2012-03-05 17:50:15 MST (-0700)

Yes, you’re right, now that I look at it: K does cause this thing to darken considerably. But there’s no color change, it’s just cortex becoming transparent. Still considered negative.

Dang, I gotta be careful with these things. Coulda sworn this was a Physcia by the photo!

I knew something was up.
By: Andrew Khitsun (Andrew)
2012-03-05 17:31:54 MST (-0700)

I’m not well versed in Phaeophyscia ciliata yet, but I decided to send you a specimen after seeing these things after rain – they were very dark, not like Physcia aipolia at all. Color in photos appears to be right – that’s how they look everyday (That’s at my workplace). The difference between this one and what I’ve come to know as “normal” Phaeophyscia ciliata is astonishing, though.
As far as interpreting the K test, I was only certain that apothecia rims darkened. Other faint changes I mentioned may or may not have happened – lichen change colors when wet, regardless of what the wetting agent is, and my ability to interpret the color tests is very limited at best (unless it changes blood red and stays so). As far as mixups go, if the things you got from me look like tiny knobs (or half-spheres) – it’s got to be it!

Just looked at the specimen you sent me
By: Jason Hollinger (jason)
2012-03-05 17:04:49 MST (-0700)

Wow, the color in the photos was misleading. This isn’t a Physcia at all. It’s tiny and very closely appressed, but not Hyperphyscia because it has lots of tiny rhizines. Must be a small form of Phaeophyscia ciliata. Wow, how wrong could we be?? (Both cortex and medulla are K- in the specimen you gave me. There’s always the slight possibility that specimen and photos don’t correspond — it happens to the most conscientious of us!)

Spot tests not as easy to interpret as they sound
By: Jason Hollinger (jason)
2012-02-23 02:04:38 MST (-0700)

The only substance in our Physcia that gives a positive spot test is atranorin, which is K+ yellow. It’s always in the cortex, and it’s present in the medulla in roughly half the species. It’s often described as “pale yellow” to distinguish it from the deeper/stronger yellow to orangish yellow of things like stictic acid and thamnolic acid.

The problem with K test is that K dissolves the cortex and medulla readily, and further, the cortex becomes translucent when wet. Both effects will cause color change, even if no lichen substances are present. So I’m guessing the K+ brown on the apothecia rims must have something to do with this. My recommendation – aside from the obvious “practice”! – is to make your K as strong as possible :) and apply it sparingly while watching at magnification. (This is why the dissecting scope is so handy.) Flooding the sample with K – not that you’re doing this! – doesn’t necessarily cause greater reaction. Instead it can just exacerbate the wetting and dissolving effects and potentially completely obscure the reaction you’re trying to see. This is especially true of tiny Physcia or thalli with super-thin medulla. The K+y medulla of P. subtilis is notoriously difficult to observe, for example.

I’d say in this case, if you’re just getting a very faint yellow in the medulla, especially if it took a few seconds to appear, then you’ve got K-, therefore P. stellaris.

By: Andrew Khitsun (Andrew)
2012-02-22 20:25:41 MST (-0700)

Just did a K test on this, and it came (somewhat) positive. While it seemed the medula changed its colors a bit to a very faint yellow, the apothecia rims became dark brown. The cortex colors didn’t change.

Sorry for the confusion
By: Jason Hollinger (jason)
2011-04-29 20:33:04 MDT (-0600)

I was just trying to be complete, and most references I know don’t include that species (P. dakotensis) so I figured it was worth recording its vitals someplace. Hopefully some day all these sorts of comments will be compiled and summarized into the name descriptions. Right now I’m just trying to get all the raw material out there as comments.

By: Andrew Khitsun (Andrew)
2011-04-29 20:05:44 MDT (-0600)

You talk at length about P.dakotensis, but if I understood you correctly the species in question here is either P.aipolia or P. stellaris? I failed to find a picture of P.dakotensis, but since it’s a rock-dwelling species, I think it’s out of consideration here? We also have P.adscendens here in WI, but it’s totally different. The lichen in question here grows at my work, so I can grab a piece and do a test on it at some point.

Looks unexciting, then
By: Jason Hollinger (jason)
2011-04-28 07:25:34 MDT (-0600)

Just ran down the eleven species on Jim Bennett’s checklist:

Physcia tenella – Heterodermia-like with cilia
_Physcia americana – sorediate
Physcia caesia – sorediate
Physcia dakotensis – sorediate
Physcia dubia – sorediate
Physcia millegrana – “blastidiate”
Physcia halei – rock, v. narrow lobed
Physcia subtilis – rock, v. narrow lobed
Physcia phaea – rock, broad lobed
Physcia aipolia – maculate, medulla K+y*
Physcia stellaris – emaculate, medulla K-*

What the heck is P. dakotensis, though?? It is not in Sonoran Flora or in Ryan’s keys, but CNALH shows it occurring in southern Missouri, and sure enough, it is covered by the Ozark keys:

Physcia dakotensis Essl.
Sporadic, but locally common, on exposed siliceous rocks in glades, open rocky prairies and pastures, and on bluff summits. This lichen occurs on small cobbles and large boulder and bedrock expanses. It is more common in the western half of the Ozarks.

Keys out as:
1a. Sorediate.
2b. Lobes to 0.5 mm broad; soredia prevailingly marginal or terminal, without well-defined soralia.
6a. Thallus saxicolous on siliceous rocks; lobes typically ca. 0.15 mm, long and narrow, or to 0.3 mm broad and slightly fan-shaped, and closely appressed, but lobes more than twice as long as wide; soredia granular.
7a. Lobes confluent, > 0.15 mm broad; lower cortex rudimentary or lacking; soredia mostly near lobe tips; usually in exposed sites.

CNALH map suggests that it is most common in the Dakotas and western Minnesota.

didn’t like the appearance
By: Andrew Khitsun (Andrew)
2011-04-27 19:45:14 MDT (-0600)

I just though it was odd that they were so knobby – basically entire trunk covered in knobs like that (the tree in question is an ash). I’m used to more flattened (and larger in occupied area) appearance of those two species. I thought out of 11 species of physcia in WI it might be something else. I guess it was the moment I was tired of looking for the common denominator and was seeking some excitement. There is no excitement in P.aipolia and P.stellaris :-)

I assume you must…
By: Jason Hollinger (jason)
2011-04-27 19:18:35 MDT (-0600)

have some unspoken reservations about calling this Physcia aipolia or P. stellaris? (I still rely on the “crutch” of doing the K test on the medulla to distinguish the two species.)

Created: 2011-04-27 19:06:49 MDT (-0600)
Last modified: 2012-03-05 17:06:06 MST (-0700)
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