Those are not the pictures you asked your question about ? This is the one you wanted us to see on imgur, which has algae.

So you have moss on the trunk. You can remove it with tweezer. I know. Lots of work, but it works. Or you can just use an old toothbrush with some water and genntle brus it off.

THe larger green blobs with the little cups on it are liverwort, a non-vascular plant like moss which thrives on anaerobic wet soils.

Combine this with your foliage which is pale and not growing I would say your pot is too wet. Probably your plant is in a mix with lots of dense organic substrate, a potting soil of some sort. Not ideal. For starters, gently pull out the liverwort. Make sure you get the roots too. Then keep the plant a little drier. You water when the top of the soil turns dry, not before. (And not only when the whole pot it dried out!)

Ahaha sorry that was for another post :silly:
Both my trees got a bit more water than they should
Thanks for the heads up

Thank for your answer!
After the storm and lots of rain for a sequence of days I shouldn't have watered the trees just two days later. And I was also worried about the high temperatures here in the south of Portugal (30ºCelsius). Newbie mistake, still learning
I will be more attentive regarding the dryness of the soil
Thank you once more
All the best!