Limnophila sessiliflora (Vahl) Blume

Family: Scrophulariaceae

Common names:  ambulia, limnophila, Asian marshweed

Disseminule:  Seed

Description

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.

Distribution

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.

Habitat

Mostly aquatic; damp soils, ditches, mountain streams, wet areas along rivers and lakes, in water to 3 m deep.

General information

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. L. sessiliflora is resistant to chemical control and is reported to outcompete Hydrilla.

Seeds

Hilar end of seed

A, Seed; B, longitudinal section of seed showing embryo; C, transection of seed

drawing by Lynda E. Chandler

Fruit