The water clover Marsilea quadrifolia is native in Europa and western Asia and has also been introduced into North America. In Germany it is considered extinct or missing, and it is strictly protected by the German Federal Act for the Conservation of Nature. It was mainly found in the Upper Rhine region as marsh plant in waterbodies poor in nutrients.
In trade, the plant sold under the name Marsilea quadrifolia is a water clover that is highly suitable as aquarium plant, however, it may be doubted whether it really has been identified correctly. In trade, you often also see the names M. crenata, M. hirsuta, M. exarata, M. drummondii and M. quadrifolia, however, it is not sure whether the respective plant was identified correctly. Most species of the genus Marsilea can only safely be identified in their emersed form by means of their sporocarps (spore-containing fruit).
Please see Marsilea spp.
<a href="https://www.flowgrow.de/db/aquaticplants/marsilea-quadrifolia" target="_blank"><img alt="Marsilea quadrifolia" title="Marsilea quadrifolia" src="https://www.flowgrow.de/db/widget/aquaticplants/marsilea-quadrifolia" /></a>
[url=https://www.flowgrow.de/db/aquaticplants/marsilea-quadrifolia][img]https://www.flowgrow.de/db/widget/aquaticplants/marsilea-quadrifolia[/img][/url]
[widget=aquaticplants/marsilea-quadrifolia]Marsilea quadrifolia[/widget]