Alismataceae

Plant Sex: Monoecious, dioecious, polygamous or flowers bisexual.

Flowers: Actinomorphic,3-merous, otherwise much like Ranunculaceae! Note APOCARPOUS gynoecium, unusual for monocots.

Inflorescence: Racemes or panicles. Secondary branches often whorled.

Fruits: Achenes or nutlets borne on a "head".

Habit: Aquatic perennial herbs.

Leaves: Often arising from a corm or rhizome. Leaves with long, spongy petioles. Blades lanceolate or sagittate in shape.

Examples:
Sagittaria

S. montevidensis. Leaf. Flowering plant. This species is cultivated as an ornamental. Staminate flower.
S. lancifolia (arrowhead, swamp potato). Excavated plant in hand. Flower.
S. latifolia. Inflorescences of this monoecious plant. Young infructescences.
S. sp. Excavated rhizome.

Alisma

A. plantago-aquatica (water plantain). Habit of plant. Inflorescence (tiny flowers!). Flower to fruit developmental series. Fruits.

SIUC / College of Science / Elements of Plant Systematics
URL: http://www.plantbiology.siu.edu/PLB304/Lecture24Liliales/Alismataceae.html
Last updated: 29-Mar-08 / dln