Often relatively species-rich, grassy, flowery formations characteristic of the upper levels of the salt meadows of the Atlantic and its connected seas, with Armeria maritima, Glaux maritima, Plantago maritima, Frankenia laevis, Artemisia maritima, Festuca rubra, Agrostis stolonifera, Juncus gerardi, Carex extensa, Blysmus rufus, Eleocharis spp. Similar communities occupying the lower levels of brackish meadows, in particular of the Baltic, are included, while formations restricted to brackish conditions are listed under unit A2.521. The dominance of various species induces distinctive facies, the most important of which are individualised in subunits.