The name Water-starwort (Callitriche) identifies species of a small group of aquatic plants that typically have their greatest expansion in late winter and spring. They are plants rooted in substrates of shallow waters with thin and narrow leaves along a slender stem and always ending at the top with some leaves organized in a starlet. These starlets are almost always floating on the water surface.

Their habitat can be moving water from streams or rivers to stagnant waters of ponds or even temporary pools that offer water only a few months of the year.

In Portugal, water-starwort was much appreciated in times of famine and prepared as a green broth, since the plant is edible. But not only man was looking for these plants. Different species of newts also like its thin leaves, as they serve to lay egg by egg in folded stem leaves of this aquatic plant.

Do not confuse Water-starwort with duckweed which are a group of aquatic plants with floating leaves but without being rooted to the bottom.

In biological pools, the Water-starwort is used as an oxygenating plant, often planted where the water flows, for example, in a stream where the water from the filter returns to the bathing area.