The family Saururaceae is classified in the order Piperales, and belongs to an ancient group of flowering plants, the magnoliids, which are characterised by flower parts in multiples of 3 (like the monocots, but unlike most other dicots) and which also includes the nutmeg, laurel, custard apple, magnolia and black pepper families. The family is most closely related to the black pepper family (Piperaceae).
Despite its long history, it is a small family with four genera and only six species of moisture loving and aquatic plants from eastern Asia and North America, which share the following characters:
- Leaves are arranged alternately along the stem (though sometimes clustered at the base of the stem).
- Leaves often heart-shaped.
- Stems often jointed.
- Leaves, stems and roots aromatic.
- Flowers have both male (anthers) and female parts (stamens), but have no petals or sepals.
- Flowers are borne in dense spikes or racemes.
The jointed stems and heart-shaped leaves means that members of this family are sometimes mistaken for Japanese Knotweed (Fallopia japonica).
Some species you might find in UK gardens are described below.
Species belonging to this family can be separated into two groups: those with petal-like bracts at the base of the flower spikes, and those without.
1. Flowering heads with petal-like bracts at the base
Photo on left by Dalgial (Wikimedia, CC BY-SA 3.0). Photo on right by Shutterstock.Flowering heads with petal-like bracts at the base
2. Flowering heads without petal-like bracts at the base
Photo on left by fredlyfish4 (Wikimedia, CC BY-SA 4.0). Photo on right by Fritzflohrreynolds (Wikimedia, CC BY-SA 3.0).
Photos by Alpsdake (Wikimedia, CC BY-SA 4.0).