Hypericaceae is a plant family in the order

Malpighiales The Malpighiales comprise one of the largest orders of flowering plants, containing about 36 families and more than species, about 7.8% of the eudicots. The order is very diverse, containing plants as different as the willow, violet, poinsett ...

, comprising six to nine genera and up to 700 species, and commonly known as the St. John's wort family. Members are found throughout the world apart from extremely cold or dry

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

s. ''

Hypericum ''Hypericum'' is a genus of flowering plants in the family Hypericaceae (formerly considered a subfamily of Clusiaceae). The genus has a nearly worldwide distribution, missing only from tropical lowlands, deserts and polar regions. Many ''Hy ...

'' and '' Triadenum'' occur in temperate regions but other genera are mostly tropical.

Characteristics

Members of this family are

annual Annual may refer to: *Annual publication, periodical publications appearing regularly once per year ** Yearbook ** Literary annual *Annual plant *Annual report *Annual giving *Annual, Morocco, a settlement in northeastern Morocco *Annuals (band), ...

perennial A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also wid ...

herbs, subshrubs or shrubs. The leaves are simple and entire, in opposite pairs; they are sometimes dotted with black or translucent glandular spots. The

inflorescence An inflorescence is a group or cluster of flowers arranged on a Plant stem, stem that is composed of a main branch or a complicated arrangement of branches. Morphology (biology), Morphologically, it is the modified part of the shoot of sperma ...

consists of a branched, flat-topped cluster, each flower being radially symmetrical, with a superior ovary. Flowers have the following components:

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 The term ''sepalum'' was coine ...

s, four or five, which tend to persist; petals four or five, usually yellow, sometimes dotted with black specks; stamens many, on long filaments; styles, three to five, often fused at the base. The fruit has a dehiscent capsule which splits open when ripe to release the fine black seed.

Taxonomy

At one time, this family was accepted as a subfamily of the family

Clusiaceae The Clusiaceae or Guttiferae Juss. (1789) (''nom. alt. et cons.'' = alternative and valid name) are a family (biology), family of plants including 13 genera and ca 750 species. Several former members of Clusiacae are now placed in Calophyllaceae ...

. Now it has been elevated to full family status. In '' Phytotaxa'', six genera and around 590

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

are listed, whereas '' The Plant List'' recognises nine genera and around 700 species. Members of the family are found worldwide except in excessively cold or dry areas. Most of the genera are mainly tropical, but ''

'' and '' Triadenum'' are found in temperate regions. Molecular data supports the

monophyly In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

of Hypericaceae. When accepted as a complete family, the cladogram of Hypericaceae would appear as such:

Pharmacology

Many members of this family contain the

naphthodianthrone ''For the parent molecule 9,10-anthraquinone, see anthraquinone'' Anthraquinones (also known as anthraquinonoids) are a class of naturally occurring phenolic compounds based on the 9,10-anthraquinone skeleton. They are widely used industrially an ...

derivatives

hypericin Hypericin is a naphthodianthrone, an anthraquinone derivative which, together with hyperforin, is one of the principal active constituents of '' Hypericum'' ( Saint John's wort). Hypericin is believed to act as an antibiotic, antiviral and non- ...

and pseudohypericin; these are contained in glandular tissues that appear as black, orange or translucent spots or lines on petals, leaves and other parts of the plant. These compounds are

photosensitive Photosensitivity is the amount to which an object reacts upon receiving photons, especially visible light. In medicine, the term is principally used for abnormal reactions of the skin, and two types are distinguished, photoallergy and phototoxicit ...

and can cause reactions in grazing animals, such as blistering of the muzzle, as well as in people who come into contact with the plants over prolonged periods. The highest concentration of these substances occurs in common St. John's wort (''Hypericum perforatum''), which is used in

herbalism Herbal medicine (also herbalism) is the study of pharmacognosy and the use of medicinal plants, which are a basis of traditional medicine. With worldwide research into pharmacology, some herbal medicines have been translated into modern reme ...

and as a

folk remedy Traditional medicine (also known as indigenous medicine or folk medicine) comprises medical aspects of traditional knowledge that developed over generations within the folk beliefs of various societies, including indigenous peoples, before the ...

References

External links

Hypericaceae of Mongolia in FloraGREIF
{{Authority control Hypericaceae