Glossostigma diandrum is a small submerged rooted aquatic plant. It forms mats and grows attached to rocks in seasonal or perennial freshwater streams and shallow waterlogged areas. G. diandrum is native to Asia and Australia.
Foliage
The leaves are glabrous and narrowly elliptic to oblanceolate. They are from 0.06-0.6 in. (1.5-14 mm) long.
Flowers
G. diandrum has mostly cleistogamous flowers but some may open leading to insect pollination. It usually flowers after rain.
Fruit
G. diandrum often spreads vegetatively.
Ecological Threat
G. diandrum grows along freshwater lakes, ponds, streams and rivers attached to rocky substrate. It is widely distributed worldwide and is considered an invasive species in the United States.