Aponogeton
Description
Perennial waterplants with a tuberous, elongate or cylindrical and often branched rootstock or rhizome which produces a tuft of leaves and the inflorescences.
Leaves submerged and/or floating (very seldom emerged), with a mostly distinct midrib and one or more pairs of parallel main nerves, connected by numerous cross-veins.
Inflorescence long-peduncled, emerging above the water surface, in bud enveloped by a caducous or rarely persistent spathe, composed of 1 (in Mal.) or 2-11 spikes.
Flowers (in Mal.) bisexual, spirally arranged, turned towards all directions.
Stamens 6, in 2 whorls.
Ovaries 3(-4-5), free, sessile, narrowed into the style with a stigmatic ridge on the inner side;
Fruits with a mostly distinct, lateral or terminal, often curved beak.
Seeds without endosperm;
Distribution
Africa present present, Asia-Tropical: India present, Ceylon present, Ethiopia to the Cape present, Madagascar present present, Malesia to SW., N. and E. Australia (to 34° SL) present, to c. 30° NL present
About 40 spp. described, from Africa (Ethiopia to the Cape), Madagascar, India&Ceylon, through SE. Asia (to c. 30° NL) and Malesia to SW., N. and E. Australia (to 34° SL), centering in Africa and Madagascar.
Uses
In Malesia none. The starchy tuberous rootstock of most species is edible and seems to be in some areas an important food source in times of famine. The leaves and inflorescences can serve as a vegetable. Many species are in cultivation with aquarists.