''Paris quadrifolia'', the herb Paris or true lover's knot, is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Ancient Greek, Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed with ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Melanthiaceae Melanthiaceae, also called the bunchflower family, is a family (biology), family of flowering plant, flowering herbaceous perennial plants native to the Northern Hemisphere. Along with many other lilioid monocots, early authors considered member ...

. It occurs in temperate and cool areas throughout

Eurasia Eurasia ( , ) is a continental area on Earth, comprising all of Europe and Asia. According to some geographers, Physical geography, physiographically, Eurasia is a single supercontinent. The concept of Europe and Asia as distinct continents d ...

, from

Spain Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with territories in North Africa. Featuring the Punta de Tarifa, southernmost point of continental Europe, it is the largest country in Southern Eur ...

Yakutia Sakha, officially the Republic of Sakha (Yakutia), is a republics of Russia, republic of Russia, and the largest federal subject of Russia by area. It is located in the Russian Far East, along the Arctic Ocean, with a population of one million ...

, and from

Iceland Iceland is a Nordic countries, Nordic island country between the Atlantic Ocean, North Atlantic and Arctic Oceans, on the Mid-Atlantic Ridge between North America and Europe. It is culturally and politically linked with Europe and is the regi ...

Mongolia Mongolia is a landlocked country in East Asia, bordered by Russia to the north and China to the south and southeast. It covers an area of , with a population of 3.5 million, making it the world's List of countries and dependencies by po ...

. It prefers

calcareous Calcareous () is an adjective meaning "mostly or partly composed of calcium carbonate", in other words, containing lime (mineral), lime or being chalky. The term is used in a wide variety of Science, scientific disciplines. In zoology ''Calcare ...

soils and lives in damp and shady places, especially old established woods and stream banks. ''P. quadrifolia'' is in decline in

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

due to

loss of habitat Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...

. In Iceland, for example, it is on the red list.

Description

''P. quadrifolia'' is a

perennial In horticulture, the term perennial ('' per-'' + '' -ennial'', "through the year") is used to differentiate a plant from shorter-lived annuals and biennials. It has thus been defined as a plant that lives more than 2 years. The term is also ...

herbaceous plant Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials. Definitions of "herb" and "herbaceous" The fourth edition o ...

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 A whorl ( or ) is an individual circle, oval, volution or equivalent in a whorled pattern, which consists of a spiral or multiple concentric objects (including circles, ovals and arcs). In nature File:Photograph and axial plane floral diagra ...

of four leaves. Each plant produces at most one blueberry-like

berry A berry is a small, pulpy, and often edible fruit. Typically, berries are juicy, rounded, brightly colored, sweet, sour or tart, and do not have a stone or pit although many pips or seeds may be present. Common examples of berries in the cul ...

, , 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 Vehicle weight is a measurement of wheeled motor vehicles; either an actual measured weight of the vehicle under defined conditions or a gross weight rating for its weight carrying capacity. Curb or kerb weight Curb weight (American English) or k ...

includes 14.5%

carbohydrate A carbohydrate () is a biomolecule composed of carbon (C), hydrogen (H), and oxygen (O) atoms. The typical hydrogen-to-oxygen atomic ratio is 2:1, analogous to that of water, and is represented by the empirical formula (where ''m'' and ''n'' ...

s and 2.6%

lipid Lipids are a broad group of organic compounds which include fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides, diglycerides, phospholipids, and others. The functions of lipids include storing ...

s.. The berry is poisonous, because it contains

solanine Solanine is a glycoalkaloid poison found in species of the Solanaceae, nightshade family within the genus ''Solanum'', such as the potato (''Solanum tuberosum''). It can occur naturally in any part of the plant, including the Leaf, leaves, frui ...

, 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 Bilberries () are Eurasian low-growing shrubs in the genus ''Vaccinium'' in the flowering plant family Ericaceae that bear edible, dark blue berries. They resemble but are distinct from North American blueberries. The species most often referre ...

Raphide Raphides ( ; singular ''raphide'' or ''raphis'') are needle-shaped crystals of calcium oxalate monohydrate ( prismatic monoclinic crystals) or calcium carbonate as aragonite ( dipyramidal orthorhombic crystals), found in more than 200 familie ...

s occur in at least the

perianth The perianth (perigonium, perigon or perigone in monocots) is the non-reproductive part of the flower. It is a structure that forms an envelope surrounding the sexual organs, consisting of the calyx (sepals) and the corolla (petals) or tepal ...

, 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 Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming o ...

in 1753.Linné, Carl von, & Salvius, Lars. (1753). Caroli Linnaei ... Species plantarum :exhibentes plantas rite cognitas, ad genera relatas, cum differentiis specificis, nominibus trivialibus, synonymis selectis, locis natalibus, secundum systema sexuale digestas... (Vol. 1, p. 367). Impensis Laurentii Salvii. https://www.biodiversitylibrary.org/page/358386

Ecology

In some patches studied by Ehrlén and Eriksson 1993, '' Clethrionomys glareolus'' and ''

Apodemus ''Apodemus'' is a genus of Muridae, murid (true mice and rats) containing the field mice as well as other well-known species like the wood mouse and the yellow-necked mouse. The name is unrelated to that of the ''Mus (genus), Mus'' genus, instead ...

'' sp. removed up to 80% of the fruits. They are graniviorous, consuming most of the seeds but only a small proportion of the fruit's pulp. As some seeds inevitably escape predation, they also act as seed dispersers.

Etymology

The specific epithet ''quadrifolia'' means four-leaved.Spektrum der Wissenschaft. (2013, September 16). ''Paris quadrifolia''. Lexikon Der Arzneipflanzen Und Drogen. Retrieved May 19, 2025, from https://www.spektrum.de/lexikon/arzneipflanzen-drogen/paris-quadrifolia/10783

Conservation

It is categorised as a species of Least Concern (LC) according to the

IUCN The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status ...

red list.

Gallery

File:20170922-paris quadrifolia-einbeere.jpg, File:Paris quadrifolia in Little Sorn burnside.jpg, File:Paris quadrifolia fruit - Keila.jpg, File:Paris quadrifolia.JPG, File:Little Sorn and Cessnock Water.JPG,

References

Bibliography

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External links

HoloGuides - photos
Melanthiaceae Flora of Europe Flora of Asia Plants described in 1753 Taxa named by Carl Linnaeus {{liliales-stub