Description: Herbs or small shrubs, aquatic or terrestrial.
Leaves alternate, opposite or whorled, simple, margins entire, toothed or deeply dissected; stipules absent.
Inflorescences of axillary dichasia or terminal thyrsoids, sometimes reduced and spike-like. Flowers actinomorphic, bisexual or sometimes unisexual and then plants dioecious or monoecious; usually 4-merous or sometimes 2- or 3-merous. Sepals free, persistent on fruit. Petals free, sometimes absent. Stamens equal to or twice as many as the sepals; filaments slender, free. Ovary inferior usually 4- or sometimes 2- or 3-locular; styles mostly equal in number to the sepals; stigmas ± capitate.
Fruit a 1–4-seeded nut, usually indehiscent but splitting into four 1-seeded mericarps in Myriophyllum.
Distribution and occurrence: World: 8 genera, c. 152 species, mainly Southern Hemisphere. Australia: 6 genera, 109 species, all States.
Angiosperm Phylogeny Website (Family: Haloragaceae, Order: Saxifragales)
Text by Peter G. Wilson
| ||Key to the genera|| |
|1||All flowers with petals; terrestrial plants||2|
|Female flowers lacking petals; aquatic herbs||Myriophyllum|
|2||Flowering shoot not ending with a flower; anthers not apiculate||3|
|Flowering shoot terminating in a flower; anthers shortly apiculate|
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|3||Fruits 2–4-locular, woody; flowers usually in axillary groups of 3–7||Haloragis|
|Fruits 1-locular, membranous; flowers usually solitary in axils|
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|4||Leaves opposite, regularly toothed; inflorescences narrow and spike-like||Haloragodendron|
|Leaves alternate, entire; inflorescences spreading and umbel-like|
Back to 2