Observation 115229: Punctelia hypoleucites (Nyl.) Krog
When: 2012-09-01
Herbarium specimen reported

Proposed Names

57% (1)
Recognized by sight
86% (1)
Eye3 Eyes3
Used references: ID provided by Jim Bennett

Please login to propose your own names and vote on existing names.

Eye3 = Observer’s choice
Eyes3 = Current consensus


Add Comment
Jim Bennett identified this as P.hypoleucites
By: Andrew Khitsun (Andrew)
2014-06-25 22:56:07 CDT (-0400)
People who created the microscope are responsible for all these troubles :-)
By: Andrew Khitsun (Andrew)
2012-11-02 21:53:16 CDT (-0400)

Otherwise we would’ve dealt with just one species, and P. hypoleucites and P. graminicola would’ve been just mere synonyms. I think I’m beginning to understand those who burnt scientists on bonfires in the middle ages – the inquisitive ones create too many problems, and the rest of us have to live with it :-)
PS. And I was “sleeping at the wheel” (I always do)

These C+ pink/red acids seem to be inherently variable
By: Jason Hollinger (jason)
2012-11-02 01:08:32 CDT (-0400)

For the longest time I was convinced lecanoric acid was C+ persistent strong red, and gyrophoric acid was C+ fleeting pink. However, in fact, it seems to depend on concentration of the acid and your bleach. I’ve now seen fleeting lecanoric acid, and really strong persistent gyrophoric acid. This is why, I think, you’ll find authors differing on their descriptions of C and KC tests.

At this point I mostly ignore the exact wording; the important thing is whether it reacts with C/KC pink or red at all (C+ / KC+ orange means xanthones, a totally different family of substances). There are relatively few cases where you need to distinguish between (C+r KC+r) and (C- KC+r). Parmotrema, maybe. Oh, right, and Hypotrachyna. That’s where I learned this lesson the hard way.

The point is you got KC+ pink out of this, therefore it is definitely in the C+/KC+ group, not the C-/KC- group. I think variation in concentration, variations within the same thallus, strength of bleach… any of these factors could explain the apparent C- test. This is why it’s always good to do the KC test just to be sure (like you did!) — C test can be flaky, but KC test rarely is.

PS. Thomson calls the cortex of P. hypoleucites K+y, not the medulla, I think you might’ve been falling asleep at the wheel! :)

PPS. Also, P. hypoleucites and P. graminicola are supposedly indistinguishable (at least not reliably distinquishable) by morphology or spot tests. We either have to trust the odds based on recorded abundance of the two species in that area, or we need to start measuring the silly conidia. Not a satisfying answer, but there it is.

P. hypoleucites is listed in Adams county where this area is located.
By: Andrew Khitsun (Andrew)
2012-11-01 21:43:38 CDT (-0400)

And that other observation in particular (observation 99471), with its “baby” apothecia and black pycnidia, looks similar to a photo in Brodo. But chemistry seems to be all over the place. On the other hand, authors disagree about chemistry too. While Thomson says P. hypoleucites has medula K+ yellow, Brodo says K-. Both agree on C+ red. Just to remind you, the other observation was medula K-, C+ red, so it does fit Brodo’s P. hypoleucites. Perhaps, this one here is P. graminicola then? But then again, I need to let someone more experienced to test it too – I remember not long ago “discovering” that different parts of thallus test differently, and this one being on rock doesn’t mean I’ve got the best material – rather what I could scrounge off of that rock.

By: Jason Hollinger (jason)
2012-11-01 21:15:46 CDT (-0400)

It might be worth noting that Bruce Ryan explicitly mentions that P. hypoleucites is ±reticulately ridged. (But doesn’t say one way or the other from P. graminicola.)

I think it’s the same as observation 99471
By: Andrew Khitsun (Andrew)
2012-11-01 20:43:36 CDT (-0400)

Except, this time there is no black dots (pycnidia?) and “baby” apothecia. Also, while it’s K- on medula, it’s KC+ pink, but C- (unlike the other one). I know my C is old and needs replacement – maybe that’s the issue. Otherwise, the lower surface is almost white, with simple brown rhizines.

Created: 2012-11-01 20:40:41 CDT (-0400)
Last modified: 2015-12-16 14:47:49 CST (-0500)
Viewed: 33 times, last viewed: 2016-10-21 19:38:39 CDT (-0400)
Show Log