Observation 217000: Opegrapha calcarea Turner ex Sm. & Sowerby
When: 2015-09-26
Who: zaca
No herbarium specimen

Notes: Growing on calcareous rock in the intertidal zone; the rock becoming half submersed at the higher level of the sea (see the photo of the habitat).

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Microscopy added.
By: zaca
2015-09-28 14:14:39 PDT (-0700)

After the changes mentioned in my last comment, here I consider the specimen in the first photo for which the microscopy seems to point to Opegrapha calcarea. I obtained the following dimensions for the spores (mount in KOH and Congo red):
(13.7) 15 – 18.5 (18.7) x (2.8) 3.2 – 4 (4.4) µm
Q = (3.6) 3.9 – 5 (6.1) ; N = 21
Me = 16.6 × 3.7 µm ; Qe = 4.5 .

Problem found.
By: zaca
2015-09-28 14:03:29 PDT (-0700)

When I created this observation I thought to have inserted a text in the notes where I mentioned to be astonished with the proliferation of specimens at this place. They were so many and most of them had no definite thallus. I collected three samples from there. Now, when I started to analyse the material, the first one revealed to be of another species than O. calcarea and actually of another genus (due to the changes in taxonomy) – Alyxoria varia. I had already encountered this species and it has a special feature, the lirellas are open at maturity, and this can be seen at the full magnification of the photos. Since it can happen that other species are envolved, I will keep this observation for Opegrapha calcarea and will remove the photos of the specimens for which I have no sample, except the one with the collage. In accordance, I will create another observation for A. varia.

Created: 2015-09-26 16:39:40 PDT (-0700)
Last modified: 2015-09-28 14:13:25 PDT (-0700)
Viewed: 41 times, last viewed: 2017-05-11 15:20:08 PDT (-0700)
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