Contemporary Circumscription Compared with A Utah Flora 4th ed.

Bio430

Alismataceae

No differences

Key Features

Aquatic herbs with milky juice growing from creeping rhizomes.  Leaves are estipulate, mostly basal (produced alternately with reduced internodes so the stem is very short), simple, petiolate, and either lacking a blade or with an oval to saggitate blade; the primary veins in the leaves converge at the apex.  Inflorescences are scapose with verticillate flower clusters associated with bracts at nodes.  Flowers have three sepals, three petals, 6-many stamens and 6-many free carpels that mature into achenes (or rarely follicles).  Like Ranunculaceae in the eudicots, Alismataceae in the monocots has the primitive features of many free reproductive structures.  Plants may be synoecious, but monecious or dioecious species are common.