Altitudinal distribution: mesomediterranean belt (potential vegetation: evergreen broad-leaved forests dominated by Quercus ilex)
Note: a supralittoral Mediterranean-Macaronesian species found on steeply inclined to underhanging surfaces of a wide variety of rocks (mainly calcareous) exposed to humid maritime winds, mostly in rather shaded situations; much rarer and less heliophytic than R. phycopsis, also reported from the base of the Western Alps (France).