Alternative names: Not Applicable

Description:
Perennial or less often annual aquatic or marsh plants containing a milky latex, with a rhizome; leaves basal, subdistichous, petiolate, erect (in S.Aust. species).

Flowers bisexual or unisexual (then usually monoecious), with 3 sepals and 3 petals, arranged in tall pedunculate usually trimerous racemes or panicles; stamens 3-numerous; ovary of 2-numerous free or rarely united carpels, with a single style and usually a single (rarely several) basal or ventral ovule.

Fruit a follicle, drupe or achene with exendospermous seed(s).

Distribution:  13 genera and 70-90 species, cosmopolitan; 4 genera and 9 species in Australia. (H. I. Aston (1973) Aquatic plants of Australia).

Biology: No text

Key to Genera:

1. Flowers mostly unisexual; stamens numerous; carpels numerous	SAGITTARIA 3.
1. Flowers bisexual; stamens 6; carpels c. 6-20
2. Ripe carpels c. 20, 1-seeded, rounded at the summit	ALISMA 1.
2. Ripe carpels 6-10, 2-seeded, tapering into a long pointed beak	DAMASONIUM 2.

Author: Prepared by J.P. Jessop