Observation 66329: Collema tenax (Sw.) Ach.
When: 2011-04-19
Who: zaca
No herbarium specimen


Microscopy: Ascus (top left); Spores (top right and bottom left); Chains of a cyanobacteria of the genus Nostoc (bottom right).
3 others specimens. The one at the top observed in the same day and at the same place. The others three days latter and nearby.

Proposed Names

19% (2)
Recognized by sight
-56% (1)
Used references: do google search and look at Stephen Sharnoff’s photos of this species, dead match
61% (2)
Eye3 Eyes3
Used references: CNALH

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Eye3 = Observer’s choice
Eyes3 = Current consensus


Add Comment
I must say …
By: zaca
2011-04-27 14:26:13 PDT (-0700)

that I learned a lot with these last observations and, particularly, with this one. This place seem to be terrific for species associated with the cyanobacteria Nostoc. I observed some others that I will post in different observations. Concerning the species of this observation I will soon upload a new set of pictures with different specimens.
Thanks, Jason, for your support and comments.
To Christian I must say that I also admire his work, particularly, the recent one with the spores of an Amanita sp..

You lichen people
By: Christian (Christian Schwarz)
2011-04-26 16:22:41 PDT (-0700)

are really getting the job done! Admiration!

Nicely done!
By: Jason Hollinger (jason)
2011-04-26 16:10:22 PDT (-0700)

It’s very good to get photos of reliably-determined material of these difficult, polymorphic species up on the web. Huzzah! (And how: C. tenax is one of the most polymorphic species that exists, note the zillions of subspecies and varieties and complex synonymy. :)

I just finished …
By: zaca
2011-04-26 13:47:59 PDT (-0700)

… the microscopic analysis. The ascus are 8-spored and the spores are submuriforme, transversally 3-septate, some are longitudinal 1-septate, and I obtained the following average measures: 17.7 × 7.6 µm (N=10) (see the photograph attached). This fits well with the description given in CNALH for the species C. tenax, which is common in this region of europe, and usually develops in soil, as is the case of this specimen. According to the same reference the species C. coccophorum has 1-septate spores. Thus, I believe that this is more likely C. tenax .

Created: 2011-04-26 10:45:05 PDT (-0700)
Last modified: 2011-04-26 16:08:35 PDT (-0700)
Viewed: 107 times, last viewed: 2016-10-28 00:42:23 PDT (-0700)
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