The Santalaceae, the sandalwood family, are a family of flowering plants (including trees, shrubs, and herbs) which, like other members of Santalales, are partially parasitic on other plants. Its flowers are often unisexual or bisexual. Modern treatments of the Santalaceae include the family Viscaceae (mistletoes), previously considered distinct. They are widely distributed worldwide, primarily across temperate and tropical regions. Many members of Santalaceae have a long history of human use. Due to overexploitation, several Santalaceae are of conservation concern.
Description
Santalaceae flowers are highly variable. They are generally small with a valvate perianth in a single whorl. The stamens are fused to the corolla, with a reduced calyx. Flowers may be unisexual by abortion ("flower drop"). The ovary varies from fully to partially inferior and occasionally superior, as in the tribe Anthoboleae.
Arceuthobium strictum displaying reduced leaves
The leaves are simple and can appear as well-developed and entire or reduced to scale-like structures, depending on genus. Leaves may be deciduous or persistent depending on the biome of origin.
All members of this family are holoparasitic or hemiparasistic, and have specialized organs known as haustoria that attach to the xylem and/or phloem of hosts for nutrient and water absorption. Aerial parasitism via stem haustoria has been observed in Amphorogyneae, Eremolepidaceae, and Viscaceae. Most (but not all) of Santalaceae are generalist parasites, and may parasitize multiple hosts at once.
The presence of acetylenic santalbic acid is a feature unique to the seed oils of multiple Santalales families, including Santalaceae (with the potential exception of Visaceae). Multiple types of rare fatty acids have also been observed across various other plant structures. These compounds are of interest for medical, phylogenetic, and chemical research.
