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Paris quadrifolia, the herb Paris or true lover's knot, is a species of flowering plant in the family Melanthiaceae. It occurs in temperate and cool areas throughout Eurasia, from Spain to Yakutia, and from Iceland to Mongolia. In Iceland, for example, it is on the red list.
Description
P. quadrifolia is a perennial herbaceous plant that is tall. It may have 3–8 leaves but typically there are four leaves arranged as opposing pairs. The flowers are wispy and inconspicuous.
The plant flowers during the months of June and July. It has a solitary flower with four narrow greenish filiform (threadlike) petals, four green petaloid sepals, eight golden yellow stamens, and a round purple to red ovary. The flower is borne above a single whorl of four leaves.
Each plant produces at most one blueberry-like berry, which persists for an average of 46.2 days, and bears an average of 33.6 seeds per fruit. Fruits average 89.6% water, and their dry weight includes 14.5% carbohydrates and 2.6% lipids. The berry is poisonous, because it contains solanine, as are other plant tissues. Poisonings are rare because the plant's solitary berry has a repulsive taste that makes it difficult to mistake for a bilberry.
Raphides occur in at least the perianth, the stem, the smaller cells of the rhizome, and in abundance in the root. Its raphis-cells are elongated, pointed at the ends, and much longer than the contained raphides.
Taxonomy
It was described by Carl Linnaeus in 1753.
Conservation
It is categorised as a species of Least Concern (LC) according to the IUCN red list.