Observation 92941: Lobothallia (Clauzade & Cl. Roux) Hafellner

When: 2012-04-06

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

Who: zaca

No specimen available

I am in trouble again with this genus! (see below).
This time everything ran quite well until I decided to measure the asci. In fact, I think that this maybe one of the species: L. alphoplaca, L. praeradiosa, L. radiosa, since the other I heard of has different features. According to CNALH, these species have the following characteristics for spores and asci,
L. alphoplaca:
Spores: 11-16 × 5-8(-10) µm, hyaline, simple, short-ellipsoid,
Asci: 60-75 × 20-25 µm, oblong-elipsoid;
L. praeradiosa:
Spores: (8-)9-13(-14) x 7-9.5 µm, hyaline, simple, ellipsoid to ovoid, or often subglobose to broadly ellipsoid,
Asci: 60-75 × 20 µm oblong-elipsoid;
L. radiosa:
Spores: 11-15 × 6-8.5 µm hyaline, simple, short- to long-ellipsoid,
Asci: 45 × 15 µm oblong-elipsoid.
I obtained the following values for the dimensions of the spores:
(11.1) 12 – 14.7 (16.6) x (5.6) 5.8 – 9.4 (10) µm,
Q = (1.4) 1.5 – 2.2 (2.4) ; N = 32,
Me = 13.5 × 7.3 µm ; Qe = 1.9,
which seems to rule out L. praeradiosa.
Then I measured the asci and obtained the following values:
(53.7) 59.3 – 96.4 (99.2) x (15.6) 17.8 – 32.2 (34.2) µm,
Q = (2) 2.2 – 4.5 (4.8) ; N = 21,
Me = 76.8 × 24.2 µm ; Qe = 3.3,
where some of the asci where not measured as it must be, from the begining to the end, having skipped in some of them the narrowest part corresponding to the bottom part of them. Even though The values are much bigger than for any of the species under consideration.
So, it belongs to other genus? or, what is wrong?

Proposed Names

29% (1)
Eye3 Eyes3
Based on microscopic features: CNALH.

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Eye3 = Observer’s choice
Eyes3 = Current consensus


Add Comment
You are already doing much, Thanks.
By: zaca
2012-04-19 00:41:03 CEST (+0200)
You aren’t the only one frustrated by Aspicilia sensu lato!
By: Jason Hollinger (jason)
2012-04-19 00:19:23 CEST (+0200)

You have certainly made the effort. I just wish I had anything to offer.

As you know …
By: zaca
2012-04-18 23:52:02 CEST (+0200)

(from the observations I posted before on MO that are a small percentage of the real observations) I have encountered here a huge number of specimens that I think to belong to the genus Lobothallia and ever felt a bit disappointed to be unable to reach the concrete species. So, this time having collected a sample I made the microscopy and apparently it did not helped much: I became yet more confuse. At the end I even thought that some other genus could be present.
Finally, regarding your comment concerning the attention given to details, I can only understand this practice with some rigour on it. Maybe this is a question of (de)formation!

Genus must be right
By: Jason Hollinger (jason)
2012-04-18 23:16:35 CEST (+0200)

The paraphyses are “beaded” toward the ends. This is typical of Aspicilia and Lobothallia. Given the very well-developed thallus, I see no alternative to Lobothallia. I am impressed by your attention to detail! I don’t know how much weight to give the ascus dimensions. I’ve tried a few times and always invariably got results that differ from the literature, too.

[I noticed that British Flora doesn’t even separate Aspicilia and Lobothallia. They include only Lobothallia radiosa and Aspicilia melanaspis (a Physcia-like species with K- and broad short spores like L. praeradiosa).]

Created: 2012-04-18 22:57:17 CEST (+0200)
Last modified: 2012-04-18 23:49:55 CEST (+0200)
Viewed: 31 times, last viewed: 2017-06-13 05:03:04 CEST (+0200)
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