Not sure this is an epilobium

[Philippe]

Hi

I found this littlest creeping plant in my multiplication bed. First time I ever see it in the garden, and really no idea where it can come from. It could have come with some "outdoor" potted plants, but I think I would have already seen it before then, because I only rarely get potted plants from the outside.
It may be that the "source" is somewhere in the garden, in a place that I haven't yet discovered, silently preparing a future invasion 

I have taken away the first unripe seed capsule, just in case. But here are the pics.

The leaves are not more than 3 or 4 mm wide and long, also very little. Didn't see any flower till now, they must be insignifiant.

[Lesley Cox]

It does look very like an epilobium Philippe, doesn't it. I see you have had some experience of their determination to invade so you don't need a warning, which I could well give you, as I suffer from 3 species in particular.

[Philippe]

Thanks Lesley.
We all have our invaders, and we all don't need further ones I don't especially like plants that appear alone at once and immediately set seed. Not a good sign, most of the time.
At the first sight I told myself it could be a new zealand plant, because of the caracteristic green-brown colour of the foliage ( like so many beautiful carex and grasses from there).
If there is no other better opinion about the thing in the next 2/3 days, it'll just have to say goodbye to the neighbours around!