Nymphoides peltata (S.G.Gmel.) Kuntze, 1891
Common names: Floating heart, yellow floatingheart, fringed water-lily [En], Petit nénuphar, Nymphoïde, Limnanthème [Fr], Ninfoides, watergentiaan [Nl], Seekanne, Teichenzian [De], Genziana d'acqua, limnantemio [It], Genciana acuática [Es]
IUCN Status: LC (Least Concern)
Lake Kerkini, SERRES ● Greece
Description: Aquatic bottom-rooted perennial species with underwater creeping stolons that extend up to 2 meters. Each node on a stolon can produce a new shoot and roots.
N. peltata has cordate floating leaves that are 3-15 cm in diameter, green to yellow-green in color, have purple-tinted undersides, and are attach to submerged rhizomes. The leaves have slightly wavy margins and support a lax, or loose, inflorescence of two to five yellow, five-petal flowers (2-4 cm in diameter) with fringed petal margins.
Each flower produces a 1.5-2.5 cm beaked capsule which hold many flattened seeds with stiff marginal hairs.
Biology: Depending on water temperature, N. peltata flowers between May and October in the Northern Hemisphere. Each flower survives a single day, while leaves can persist from 23-43 days. Seeds are released 32-60 days following the end of the flowering period and can germinate under hypoxic conditions. In fall, the aboveground biomass of N. peltata dies, sinks to the substrate and decomposes, and the plant overwinters as dormant rhizomes. These rhizomes can survive freezing temperatures up to -30°C. During the winter, stolons and stems either on or buried beneath the substrate can remain dormant until spring, and some small submerged leaves measuring 1-2 cm sometimes grow on these stems. After winter, the species requires light and oxygen to produce new growth and floating leaves begin to appear in spring.
Habitat: Slow-moving rivers, lakes, ponds, and reservoirs, but also swamps and wetlands. It is also known to occur in ditches, canals, break-through pools of dikes, and backwaters, especially those subject to winter flooding.
It most frequently occurs in water 1 to 1.5 m deep, but it can survive in water between 0.3 and 3.0 meters deep. The ideal substrate consists of clay or clay covered with a thin layer of sapropel.
Distribution: N. peltata is native to East Asia and the Mediterranean. It is the only species in the genus Nymphoides that can be found in temperate regions. It has been introduced in North America, South Africa and New Zeland, where it is considered as an invasive species.
Wikipedia, Nymphoides peltata
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