Plants of the Arum Family
If you have ever seen an Anthurium, or "little boy plant," then you have met a member of the Arum family.
This is a family of unique plants with mostly basal leaves and minute flowers crowded on a fleshy stalk that is often surrounded by a large, colored bract called a spathe. There are 4 to 6 small, scale-like tepals, a term used when the sepals and petals cannot be distinguished from one another. There are typically 6 (sometimes 1, 2, 4 or 8) stamens. The ovary is positioned superior and consists of 2 or 3 (sometimes 1 to 9) united carpels with the partition walls present, forming an equal number of chambers. It matures as a berry with 1 to numerous seeds.
Worldwide, there are 110 genera and 3,200 species, mostly tropical and subtropical. Note that sweet flag (Acorus) has been separated into its own family, Acoraceae. Native or common introduced genera are listed below. Several additional genera are cultivated in southern states, and some have established feral populations. Duckweeds were formerly a separate family, but genetic evidence places them within the Arum family.
Common houseplants of the Arum family include Philodendron, Dieffenbachia, and Alocasia. Many members of this family emit foul smells to attract carrion insects; the insects transport pollen from one plant to another. The foliage of a number of species contains needle-like calcium oxalate crystals. These crystals can mechanically injure the mouth and throat when eaten, or can precipitate out in the kidneys, plugging the tubules.
Key Words: Flowers and fruits on a fleshy stalk, often in a spathe.
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