Observation 128937: Acarospora placodiiformis H. Magn.

When: 2013-02-16

Collection location: Serra de Montejunto, Portugal [Click for map]

Who: zaca

No specimen available

This is closed connected with observation 122470 (see my comment there). Looking arround I found all the developing stages of the parasitism of an Acarospora on a Diploschistes. At this moment, without the possibility of scoping it, I cannot go very far on the identification of the species. It is also clear, due to the chemistry, that it cannot be A. schleicheri, my initial guess. On the other hand, the British Flora does not help, since the only species therein with C- and K+ red on thallus are A. smaragdula and A. subrufula, whose features do not match. I looked at Spanish websites and at biodiversidadvirtual there are a number of photos of the species A. placodiiformis, whose distribution is confined to South Europe, with very similar in appearance, including a greenish thallus and light brown to brown apothecia and, as the name suggests, a placodiod thallus. Comparative to my specimens, this species has big squamules (convoluted lobes?) at the centre ending by relatively wide lobes at the margin (resembling a Squamarina as is mentioned at the site) while my specimens became more areolate at the centre with small lobes at the margin. Another common feature is the color of thallus, varying from shining green (when humid) to almost white (when drying). At that site it is mentioned that such species is found on soil with gypsum, that I don’t saw at this location, but all the rock here are of calcareous origin and the existence of gypsum is known for this big location. However, at another site with a database of lichens, bdb, there is a description giving the following chemistry on thallus: C-, K-, KC-. So, again, the chemistry is wrong.
Summarizing, I think that these specimens belong to the complex of A. schleicheri but not to that species itself.


2016-March-12: Revisited (IMGP7008);
2016-March-12: Revisited (IMGP7015).

Proposed Names

58% (1)
Recognized by sight
87% (1)
Eye3 Eyes3
Recognized by sight: My acknowledgment to the lichenologist Kerry Knudsen, who determined the Acarospora species, based on the sample of the specimen that I sent him.
Based on microscopic features
Based on chemical features

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Acarospora placodiiformis seems to be endangered …
By: zaca
2017-09-17 02:23:31 HST (-1000)

and was proposed to the “The Global Fungal red list initiative”: http://iucn.ekoo.se/iucn/species_view/363880/
See also the following paper, available at Research Gate:
Violeta Atienza and José Gabriel Segarra: Preliminary Red List of the lichens of the Valencian
Community (eastern Spain), For. Snow Landsc. Res. 75, 3: 391–400 (2000) 391.

Created: 2013-02-18 10:52:21 HST (-1000)
Last modified: 2017-09-17 02:22:09 HST (-1000)
Viewed: 109 times, last viewed: 2018-01-06 00:59:34 HST (-1000)
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