Asplenium onopteris

The spleenwort (Asplenium onopteris [= A. adiantum-nigrum ssp. onopteris]) is a medium size fern with a delicate cut, triangular shape fronds which are hold by a long petiole of black colour when near the root. The 2nd photo displays the back of the frond plenty of brown, long sorus where the spores grow.

The speenwort grows in the dark, humid holm-oak forests, mainly close to the holm-oak trunks or on rocks, often together with another fern, the polypody. In Bages, the spleenwort is frequent into the evergreen oak forests in Montserrat and Sant Llorenç del Munt i l’Obac where the lime of the soil has been drained.

Its former common name of black spleenwort is now restricted to the similar species A.adiantum nigrum ssp.adiantum-nigrum, with narrow fronds and shorter petiole growing on the siliceous rocks in the Pyrenees.

[photos Florenci Vallès (1st), Jordi Badia (2nd) and Marta Queralt López Salvans (3ª)]