Forum Flora Germanica

So, if something is immersa , apothecium is immersed. Like Rinodina immersa and Clauzadea immersa.

See these immersed thalus-es, any comment to those ?
http://agrozoo.net/jsp/Galery_one_image ... f2c299ac45
http://agrozoo.net/jsp/Galery_one_image ... 9e1b6129c0
http://agrozoo.net/jsp/Galery_one_image ... 02df51004c

If something is called "immersed" you don' t know, which thing is immersed - it might be apothecia immersed in thallus, or thallus itself immersed in substratum.

If the thallus itself is immersed, this can be called endosubstratic (opposite: episubstratic) - or if immersed in rock it can be called endolithic (opposite: epilithic).

Concerning the lichens shown here (no experience) ... compare the descriptions (and similar lichens which pop up in the keys), but in your examples the thallus is indeed immersed in substratum (in rock).
https://italic.units.it/index.php?proce ... ge&num=843 (Clauzadea inmersa)
https://italic.units.it/index.php?proce ... e&num=1952 (Pyrenodesmia alociza)

On your link, https://italic.units.it/index.php?proce ... e&num=1952
part of img. no. 6 (attachment), I think you can actually see "Thallus crustose, endosubstratic" i.e., where there is thallus of Pyrenodesmia alociza, the rock surface is lowered, right at black prothallus. Depression could be optical thing, but I think not, better, with no doubt on my images.

Seems to me, none of terms describes that. Endosubstratic, endolithic, I think, means it is inside substrate. Does not mean it eats substrate away.
Read somewhere , some lichens produce week acids, so, that could dissolve calcium carbonate ...

btw, "thallus" is spelled with two "l" both in English and German. I have edited it. Michael

Thanks. Will try to remember.
Local wiki converts that to talus.