Limnophila sessiliflora (Vahl) Blume
ambulia, limnophila, Asian marshweed
Fruit a capsule with up to 150 seeds. Seeds oblong to narrowly elliptic or narrowly obovate in outline; subterete to terete, 0.5–0.8 mm long, 0.2–0.4 mm wide and thick, some curved or grooved from crowding. Testa glistening, deep purple-red, reticulate but appearing shallowly pebbled. Hilum terminal, a cavity or recessed, sometimes whitish, surrounded by a nearly black ring. Embryo axile-linear, nearly reaching both ends of seed; endosperm present.
primarily in Asia: Bhutan, China, India, Indonesia, Iran, Japan, Korea, Malaysia, Myanmar, Nepal, Pakistan, Philippines, Sri Lanka, Taiwan, Vietnam; also found in Guam, Netherlands, United States
mostly aquatic; damp soils, ditches, mountain streams, wet areas along rivers and lakes, in water to 3 m deep
Limnophila sessiliflora is a freshwater aquatic herb with submersed and emersed stems up to 4 m long. Introduced to and currently sold in the U.S. as an aquarium plant. Its stems form dense stands, clogging canals and pumping and power stations in Florida. It is a major weed of rice fields in Asia. Fast growing, it reproduces by both seeds and stem fragments. Limnophila sessiliflora is resistant to chemical control and is reported to outcompete Hydrilla.