Marsilea quadrifolia

Kleefarn ( Marsilea quadrifolia ), in the lower half

The Kleefarn ( Marsilea quadrifolia ) is an aquatic plant of the family of Kleefarngewächse.

Features

The Kleefarn is a perennial plant and forms thin, hairy rhizomes from which arise at each node roots and leaves. The rhizomes are creeping and forming grass. The plant height is 5 to 20 cm. The leaves are long-petiolate and resemble a vierfiedrigen cloverleaf, but consist of two opposite, standing close together pairs of leaves. The leaflets are folded - wide wedge-shaped and in bud position. The leaf veins are fan-shaped and closed. The Kleefarn is the only fern species whose leaves perform sleep movements.

The youth, underwater, swimming and land leaves look very similar, but only the latter form of spore capsules. These are bean- shaped and are up to second doctorate at the base of the petiole. The spores ripen in September and October.

Dissemination and locations

The Kleefarn is a Eurasian- sub-Mediterranean - sub-continental Florenelement. He comes scattered throughout Eurasia, from Europe to western Siberia to Kashmir, Northern China and Japan. In North America, he was brought. The northern boundary in Europe runs from the Loire region on the Rhine, the Upper Rhine region, the Czech Republic and Poland.

In Germany, the species is considered extinct. The last autochthonous occurrence was destroyed in the 1960s. In Baden- Württemberg there is a potentially spontaneous resettlement. At various points, the species was also angesalbt. In Austria, the kind only exists in Styria, in the other provinces it is extinct or lost. In Switzerland, the species is considered endangered and extinct regionally nationwide. There are only a few more known find sites.

The thermophilic Kleefarn grows on muddy shores of standing, nutrient- rich waters. He does not rise above the height colline level.

Documents

• Siegmund Seybold (ed.): Schmeil Fitschen - interactive ( CD -Rom ), Quelle & Meyer, Wiebelsheim 2001/2002, ISBN 3-494-01327-6