The individual plants of this tiny floating species are similar to those of other floating duckweeds, but are 'gibbous' (thick and swollen). A single root hangs down in the water below each oval plant segment.
It is rarer and more local than other duckweeds (Lemna spp. and Spirodela) and is mostly found in Lough Neagh and the connecting canals and rivers, in Upper Lough Erne, and in the lakes of eastern Co. Down.
All names: Lemna gibba L.