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Hi Paul: Best of luck with that proposal! I hope you are going to do it soon before more people start/continue to use Polyozosia.
Alan
Excellent work as always, but we need to talk about Myriolecis/Polyozosia. I totally agree with the first part of the statement on pg.61, that “the name change [from
Myriolecisto Polyozosia] serves no useful purpose” and is an act of nomenclatural vandalism. Unfortunately, the second part, that “their work… needs further examination”, is incorrect. Kondratyuk is, for once, correct (stopped clocks, and all that)! We already had molecular data from the Glacier Bay NP survey showing that Lecanora poliophaeabelonged in Myriolecis( Lichenologist52:86; Fig. 10) and were planning to make the new combination in to Myriolecisin that paper. However, when Kondratyuk published his revision, we decided to wait until the dust settled and took the conservative approach of retaining everything in Lecanora. Lecanora poliophaeais the generitype of PolyozosiaA. Massal. (1855), which clearly predates MyriolecisClem. (1909) and, as a formal proposal to reject Polyozosiais unlikely to be successful, I see no alternative but to accept Polyozosiaas the correct name for this group. Alan
Maxine: I can see hyaline tissue and what appears to be hyaline hyphae, so I suspect there is a fungus involved here as well. Your collection is clearly, morphologically similar to Moriola and it would be interesting to know if the fungus was related. If two unrelated lineages both produce these goniocysts it could prove, either that they are possibly widespread in the ascomycetes, or, if it is the same or related alga, that goniocyst formation is initiated by the alga – in which case it could have fundamental implications for how lichens in general are formed. Perhaps it’s the alga calling the shots, not the fungus…
All very interesting and lots of scope for speculation…
Alan
Hi: It’s not clear from your photos, but are you sure these are cyanobacteria and not green algae – they look very green! If they are green algae then you probably have a species of
Moriola. This is a genus of fungi that forms goniocysts consisting of a spherical shell of fungal cells up to 100 µm diam filled with cells of green algae. They are not rare in alpine habitats growing on damp soil and among bryophytes and over crustose lichens, but they also occur in lowland habitats, usually on old wood or lignum. They are interesting because the exhibit a primitive form of lichenization but haven’t been studied for c.100 years – although I have a colleague in Sweden who is trying to extract DNA from them…. They are rarely fertile so an ID to species is not possible but M. pseudomycesis a name given to some specimens. Here is a plate I made for a recent publication, but was edited out of the final paper.
Alan
Mark is right – identifying crustose lichens from macro photos is a mugs’ game. Having said that… the flexuose margin of the apothecia remind me of those of a Fuscideaso I’m wondering if you have a lignicolous specimen of F. cyathoides, which does happen. The thallus of that species contains fumarprotocetraric acid, so will be Pd+ rust-red. Alan
Ochrolechia parella is the name of the fungus that forms the lichen. Taxonomically, the lichen has no name because it is a composite organism formed by O. parella and an indeterminate number of other micro-organisms. In practice, though, the lichen is called O. parella. The thallus is the vegetative part of the lichen and contains both fungus and alga.
The fungus cannot associate with any alga it happens to come across. Different fungi associate with different algae. However, the same fungus can form very different-looking symbiosis depending on the algae it associates with. This is most evident when the algae is replaced by a cyanobacterium as the photosynthetic partner. In some cases, fungus + alga gives a folisoe (leaf) lichen, whereas fungus + cyanobacterium gives a fruticose (shrubby) lichen.
I’m not sure I understand your question.The primary fungus makes up the bulk of the lichen. What you are looking at is mostly vegetative tissue (the thallus) with the circular objects being the reproductive structures of the fungus (apothecia) . Lichens are considered a symbiosis (two different organisms living in close physical association, typically to the advantage of both) rather than a chimera (a single organism composed of cells from more than one organism). Lichens are not a single organism – the name Ochrolechia parellarefers only to the primary fungus forming the lichen. The fungus and the alga remain separate and are easily identifiable as such – the algal cells usually forming a layer just below the surface of the lichen. Actually, it is a lot more complicated than that as there are numerous other micro-organisms involved in the symbiosis (yeasts, bacteria, amoeba, etc., as well as other fungi and algae) and lichens are better considered as mini ecosystems or microbiomes. Hi Chris: Definitely R. geminatum. I wouldn’t worry too much about the habitat (most of Cumbria is pretty damp). I’ve seen it on the top of a chest tomb in a Scottish graveyard!
Alan
