After a long time, I’ve a new fern for you. It's Asplenium ruta-muraria L. of the Aspleniaceae fern-family. If you remember yourself to the earliest days of my blog, you maybe also remember, that I've already shown you a fern of this family: Asplenium trichomanes L.
The common English name of Asplenium ruta-muraria L. is “wall-rue”, while in German this plant is known as “Mauerraute” (means the same).
A. ruta-muraria - habitus
It's a small fern with only 15 – 20 centimetre long fronds. These fronds have a green stalk (rachys) with a dark brown base and a triangular outline. They are mostly double-pinnate; the leaflets are oval to cuneiform.
The sori are sitting in long rows on the ventral side of the leaflets. They are not covered by a veil (indusium).
A. ruta-muraria - habitus (closer)
This species is native to the whole northern hemisphere. As the name suggests, A. ruta-muraria grow a walls, but it's original habitat were rocks and crevices. Today, it can be found on many walls, even in cities. It's very undemanding towards the rock, but prefers lime more than acid places.