Marsilea quadrifolia

Marsilea quadrifolia L.

Marsileaceae – Water clover family

Conservation status. Critically Endangered [CR B1ab(i,ii,iii,iv)+2ab(i,ii,iii,iv)]. BDA, HD, BC.

Morphology and biology. Perennial, semi-aquatic to aquatic herb, with a slender, long-creeping rhizome. Leaf-petiole 1–20(80) cm; leaf-blade 4-foliolate, cruciform, leaflets obdeltate to obovate, with rounded apex. Sporocarps very firm, hairy, in groups of 2 or 3 on stalks near the base of the petiole, forming in the end of the summer. Heterosporous plant.

Habitats and populations. In periodically wet to flooded places – swamps, periphery of marshes, temporary pools, canals or ditches of still water, fish-ponds. The species is a hydrophyte in Bulgaria; however, it is a typical hygrophyte to the north. Populations are very fragmented. At present, 3 localities have been confirmed (near Nova Cherna village, Belene town and Obnova village), but only the population near Obnova comprises numerous individuals, growing very densely, although in a small area.

Distribution in Bulgaria. Northeast Bulgaria, Danubian Plain, Valley of Struma River (Southern), Thracian Lowland; up to 200 m alt. Some localities have been destroyed in the past; others have not been confirmed since 1930.

General distribution. C, S and E Europe, temperate Asia, introduced in eastern N America.

Threats. Climate aridisation; limited distribution of the species; drainage and drying up of the wetlands; redirection of the river beds; overgrowth of marshes; water pollution, etc.

Conservation measures taken. Protected species whose habitats need priority conservation according to the national Biodiversity Act. One of the species localities is within Persina Nature Park, a second one is in Kalimok–Brushlen Protected Site. Some localities are within sites of the European ecological network Natura 2000 in Bulgaria.

Conservation measures needed. Research on population number and range, species biology and ecology, threats. Elaboration of an action plan for protection of the species. Population monitoring. Inclusion of the locality near Obnova village in a Protected Area. Preserving of genetic material in genome resource bank. Exploration work on the possibility of re-introduction.

References. Achtarov & Jordanov 1963; Kochev & Jordanov 1981; Velev 1984; Valentine & Moore 1993; Tzonev 2005.

Authors: Daniella Ivanova, Rossen Tzonev


Marsilea quadrifolia (distribution map)

Marsilea quadrifolia (drawing)