Collection location: Serra de São Mamede, Portugal [Click for map]
It happened me before and probably will happen in the future. There are places where you go for the first time that reveal to be a nest for a certain group of lichens and particularly for some genus within. In this case the group is Collemataceae and the genus is Leptogium.
I’m still in the identication process but up to now some species can already be mentioned to exist here as fertile, namely:
- L. palmatum,
that is very common at this big location, but is rarely fertile (I saw only once fertile, see observation 182158 );
- L. ferax,
which I saw here for the first time; This is a rare species only known in Europe from Greece, France, Portugal and Spain; [EDITED: After microscopy, I conclude that this is a Collema sp., not yet identified.]
- L. gelatinosum,
a common species in Portugal, that frequently appears fertile (though I never analysed one under the micro).
Soon I will post some of these observations, but my preliminary concern goes to an unknown species that is “making me mad” (i.e. more than usual) and is the subject of this particular observation.
As is known there are two big genera in the family Collemateceae: Collema and Leptogium, which mainly differ, roughly speaking, from one another by the inexistence or existence of a cortex, respectively. Both have Nostoc as photobiont. Some other genera were segregated from Collema on the basis of having simples spores (Homothecium, Leciophysma, Leightoniella, Ramalodium and Staurolemma are examples) and others from Leptogium by the grow form (Polychidium is an example of a fruticose one, that can have another photobiont). Recently another genus was created to group many species in Collema, Scytinium, but for the purpose of these notes I will use if necessary the older terminology. Thus to my knowledge, foliose lichens in the family having septate to muriform spores belong to one of the two big genera Collema or Leptogium.
On the other hand, in both Collema and Leptogium there are species presenting tomento on the underside of lobes, particularly in the latter genus; The species with such feature existing in my country are (according to Ref. 2): L. burgessii, L. furfuraceum, L. hibernicum, L. juressianum, L. laceroides.
Now suppose you have a specimen (actually more than five) of a foliose lichen similar is appearance to many Leptogium spp., blue grey colored, having:
1) Tomento on the underside of lobes;
2) Nostoc as photobiont;
3) Double cortex, i.e. upper and lower cortex consisting of a single layer of cells;
4) 1-septate spores.
What will you call it?
That’s my problem with the specimen in this observation, since none of the species just mentioned above have the feature 4).
One could think that the spores presented here belong to a young specimen or to a non well developed apothecium. This is not true, since I was careful enough to chose oldest and convex apothecia to observe under the scope. Moreover, the above features are shared by all the specimens already analysed (four at the moment).
Finally, let me add that the spores are similar in form, septation and dimensions to those observed for the species Polychidium muscicola in observation 182157; However, I could find no similar species in this genus.
|I’d Call It That||3.0||0.00||0|
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|I’d Call It That||3.0||6.48||1||(zaca)|
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I’ve seen some amazing highly-localized populations of this species, too. And I’ve seen other species do this, too. Perfect example: I’ve been doing an inventory of a wildlife refuge with a friend for a couple of years. In all the thousands of specimens we’ve examined, we’ve only seen Ochrolechia szatalaensis once. But at that location it was covering the base of dozens of sagebrush shrubs. What a crazy thing. One really wants to understand what’s so special about that particular location. But who knows?? Just never know what you’re going to find. Keeps our life interesting! :)
Even in places that you think to know quite well is possible to get big surprises, like this big amount of specimens of a relatively rare species in a small space.
Appear to be evidence, but it seems that someone forgot (or ignored) it.
Well, except for being bigger than ours (as usual!), these look just like material I’ve seen in California. So funny that something as conspicuous as the isidia on these specimens has managed to elude the accepted literature for so long.
I start to attach to this observation the specimens found in the neighbour (at distances below 3 meters) of the original specimen, on the fence bordering a rural road, that was the habitat of them all.
A common feature of these specimens are the irregular lobes, often ascending, with abundant white hairs at the lobe tips; In none of these specimens the characteristic white rhizines are good visible, though one can saw them at some places. Some notes about each:
Sp. 2 – Very wavy lobes with abundant small white hairs at the tips; some zones crowded of mature apothecia, which also present white hairs at the margins;
Sp. 3 – Marginal lobes bigger than in previous specimens; squamulose isidia at the center of thallus;
Sp. 4 – Mature apothecia scattered and plenty of laminal squamulose isidia;
Sp. 5 – Infertile specimen also crowded of squamulose isidia at the center of thallus;
Sp. 6 – With both young (on the right) and mature apothecia (on the left).
Sp. 7 – Apothecia scattered;
Sp. 8 – Very mature specimen, lobes diminute and dense, crowded with apothecia; Thallus almost black at the center, contrasting with the green of others, starting to desintegrate.
to solve the “mistery” for me. In fact, in almost all the specimens observed the granular to squamulose isidia are present. Now, after your explanation, I´m a bit more confident on the name of these strange foliose jelly lichens.
On the other hand, the cilia on the upper surface, that gave the epithet to it, is very difficult to observe, while the white rhizines are easily observed even from above, due to the turned up of the lobe margins. Maybe, I will post some more observations of this species.
Thank you again, Jason.
I can verify that the actual Sonoran Flora (which that description came from) also claims it has no isidia. However, many other sources disagree:
Macrolichens of the Pacific Northwest, McCune 1997: “…isidia granular to squamule-like, occasionally cylindrical…”
Lichens of North America, Brodo et al 2001: “…upper surface with isidia that become flattened and lobe-like when older (often bearing little white hairs)…”
The Lichens of British Columbia, Part 1, Goward et al 1994: “…small to medium nonstratified foliose lichen, corticate above and below, isidiate, lobes loosely attached…”
Bruce Ryan helps clarify the situation. His unpublished key describes it thus: “…upper surface smooth, without isidia (according to Thomson)…” He is referring to John Thomson, citing Thomson, J.W. 1984. American Arctic Lichens I. The Macrolichens. Columbia University Press, New York.
The Sonoran Flora apparently derived many of its early treatments from Ryan’s voluminous unpublished works. This is not the first time I’ve seen typos or other oddities in Ryan’s keys show up verbatim in the Sonoran Flora.
I do not have the original source — Thomson 1984 — in front of me, so I can’t verify that his description lacks isidia, nor where he might have gotten that from. Thomson was diligent about making sure his descriptions matched previous literature accurately. So it may only mean that the species was originally described from European material that was nonisidiate. He would not have changed the description to reflect his own personal observations. Either a fault or a strength, take your pick, opinions differ. :)
I can see how this would be really hard to name the first time you saw it. But just keep an eye out for hairs at the tips (see observation 118874) and it’ll save a great deal of frustration in the future! :) As you can see with your observation, those hairs are definitely not always apparent in the field. Really need to look for them sometimes.
The description of the species Leptochidium albocilliatum can be found at
The genus “Leptochidium” by T. H. Nash, in “T. H. Nash et al. (eds.), Lichen Flora of the Greater Sonoran Desert Region. Vol 1”.
It is available at http://lichenportal.org/portal/taxa/index.php?taxon=56004, except for the part of the ascospores, which was not transcripted from the original; I add it here: “ascospores: oblong ellipsoid to ellipsoid, hyaline, 1-septate, 18-26 × 5-9 micrometer”. There you can also find the very nice photos of this species by Steffen Sharnoff.
Created: 2015-01-23 20:28:44 EST (-0500)
Last modified: 2015-01-29 15:53:11 EST (-0500)
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