Latin sagittarius – armed with arrows, referring to the arrow-head shape of the leaf blades.

Perennial herbs generally with stoloniferous or tuberous rootstocks. Leaves emergent and lanceolate to ovate or often arrow-head shaped, floating or submerged, linear and strap-like. Flower clusters in 1 or more false whorls with the lower flowers female or bisexual and upper flowers male; summer. Sepals 3, green. Petals 3, white, soon shed, sometimes blotched purple at the base. Stamens 7-many. Carpels spirally arranged, many, each with 1 ovule. Fruits winged and beaked.

Grown as margin plants or in aquaria. Several species have naturalised including: S. graminea Michx. from N America which occurs in SA, Qld, NSW and Vic often in drainage and irrigation channels. Syn. S. sinensis Sims, sometimes is sold as a cultivar of S. sagittifolia; S. montevidensis Cham. &Schltdl., Arrowhead, from S America has a rootstock without stolons and variable linear to ovate or arrow-head shaped leaves.

20 species mostly from tropical and temperate America. 4-5 species naturalised in Australia.

Division, or seed and tubers or scaly corms (known as turions) when produced.

Tubers edible and those of S. sagittifolia are cultivated in Asia and eaten cooked.

Leaves arrowhead-shaped; flowers in whorl-like clusters; fruits usually winged.

Bogin (1955), Haynes & Holm-Nielsen (1994).

Source: Spencer, R. (2005). Alismataceae. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 5. Flowering plants. Monocotyledons. The identification of garden and cultivated plants. University of New South Wales Press.