Observation 69821: Parmotrema A. Massal.

When: 2011-06-18

Collection location: Lourinhã, Portugal [Click for map]

Who: zaca

No specimen available


2nd specimen.
2nd specimen.

Proposed Names

20% (2)
Used references: Irish lichens.
Based on chemical features: See attached photos.
28% (1)
Recognized by sight

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

= Observer’s choice
= Current consensus


Add Comment
Sure you are right.
By: zaca
2011-06-30 15:50:24 PDT (-0700)

Unfortunately, I didn’t made the spot test for the 2nd specimen (I was convinced to have a single species).

Maybe I was actually right!
By: Jason Hollinger (jason)
2011-06-30 14:05:58 PDT (-0700)

K+y can only be P. chinense (P. stuppeum and P. reticulatum are both K+y turning deep blood red).

As for the second specimen… Most species, it seems, when really well-developed, can have at least some white splotches below, but yours is still fairly small, so I’d take the white splotches clearly visible in the photo as being important. It’s worth noting, though, that K+y is not an option among the four white-bottomed species:

P. hypotropum and P. hypoleucinum: K+y turning blood red
P. louisianae and P. hababianum: K-, C-, KC+/- pink

The K+y-r reaction (from salazinic acid) should be so strong as to be visible over time even through the cortex, so it should be unmistakable. If you tested that second specimen and it still came back yellow, then I’m definitely wrong about the white bottom.

Thanks, Jason.
By: zaca
2011-06-30 12:13:56 PDT (-0700)

Some notes regarding your comment:
- In the field it seems to me that both specimens are of the same species, but you probably are right pointing for two species;
- The chemical reactions on meddulla are: C-, K+ yellow, KC- (sorry, but I didn’t realize the existence of the hole in the medulla that becames black, as the result of a bad scraping);
- It may look strange but P. hypoleucinum is one of the 5 species appearing in the portuguese cheklists of lichens (the others are: P. chinense, P. crinitum, P. reticulatum, P. stuppeum), while Madeira and Azores have 9 and 10 species in the corresponding checklist, respectively.

Two species , I think
By: Jason Hollinger (jason)
2011-06-30 09:10:42 PDT (-0700)

P. crinitum has isidia, both of these specimens have soredia. The second specimen has a conspicuous white zone underneath, suggesting P. hypotropum or P. hypoleucinum (impossible to distinguish without TLC). The first can be any of several things because I can’t read the medulla chemistry from the photo. It looks most like P. chinense to me, but that’s just guesswork based on the short cilia and irregular strictly marginal soredia which eventually turn into nicely-shaped pillow-like powdery soralia. P. mellissii has coarse isidioid soredia. Most others have either no cilia, or much longer sparser cilia, or well-developed linear or pillow-shaped soralia from the first (not always). Still others have cracks in the upper surface, yellow medulla, soredia flaking off back from the tips (P. margaritatum), etc. That still leaves several(!) I probably more often than not get it wrong and have to revise my identification after doing the spot tests, though.