Hydrocotyle vulgaris

Hydrocotyle vulgaris, or water pennywort, is widely spread in Europe and is also found in North Africa, in Caucasia and Iran. In Germany it is the only native Hydrocotyle. It forms extensive populations on lakeshores and edges of ponds and mainly grows in locations poor in nutrients and lime, marshy or sandy, which may be quite dry. Water pennywort also extends into shallow water, where its leaves sometimes float on the water surface.
H. vulgaris is probably hard to find in the aquarium trade, however, it is often sold as a plant for pond edges in garden centres.
This species looks very much like the American species Hydrocotyle verticillata, only differing in a few characteristics.

As aquarium plant, H. vulgaris is a good choice for coldwater tanks, however, it also grows in warmwater tanks with temperatures of up to 28 °C. There it has proven to be a fast grower, but forms longer leaf stalks and internodes than H. verticillata, which makes H. vulgaris a good middleground plant.

To be continued...