Hypericoideae
   HOME

TheInfoList



OR:

Hypericaceae is a plant family in the order
Malpighiales The Malpighiales comprise one of the largest Order (biology), orders of flowering plants. The order is very diverse, with well-known members including willows, Viola (plant), violets, aspens and Populus, poplars, Euphorbia pulcherrima, 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, habitat refers to the array of resources, 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 manifestation of its ...
s. ''
Hypericum ''Hypericum'' is a genus of flowering plants in the family (biology), family Hypericaceae (formerly considered a subfamily of Clusiaceae). The genus has a nearly worldwide distribution, missing only from tropical lowlands, deserts and polar re ...
'' and ''
Triadenum ''Triadenum'', known as marsh St. John's worts, is a small genus of flowering plants in the family Hypericaceae. The genus is characterized by opposite, blunt-tipped leaves and pink flowers with 9 stamens. They are distributed in North America an ...
'' 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), a ...
or
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 ...
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 In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...
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 Etymology The term ''sepalum'' ...
s, four or five, which tend to persist;
petal Petals are modified leaves that form an inner whorl surrounding the reproductive parts of flowers. They are often brightly coloured or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''corol ...
s four or five, usually yellow, sometimes dotted with black specks;
stamen The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filament ...
s many, on long filaments; styles, three to five, often fused at the base. The fruit has a
dehiscent Dehiscence is the splitting of a mature plant structure along a built-in line of weakness to release its contents. This is common among fruits, anthers and sporangia. Sometimes this involves the complete detachment of a part. Structures that op ...
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 ''Phytotaxa'' is a peer-reviewed scientific journal for rapid publication on any aspect of systematic botany. It publishes on a wide range of subjects, but focuses on new species, monographs, floras, revisions, reviews, and typification issues. ...
'', six
genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...
and around 590
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), ...
are listed, whereas ''
The Plant List The Plant List was a list of botanical names of species of plants created by the Royal Botanic Gardens, Kew and the Missouri Botanical Garden and launched in 2010. It was intended to be a comprehensive record of all known names of plant specie ...
'' 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 ''
Hypericum ''Hypericum'' is a genus of flowering plants in the family (biology), family Hypericaceae (formerly considered a subfamily of Clusiaceae). The genus has a nearly worldwide distribution, missing only from tropical lowlands, deserts and polar re ...
'' and ''
Triadenum ''Triadenum'', known as marsh St. John's worts, is a small genus of flowering plants in the family Hypericaceae. The genus is characterized by opposite, blunt-tipped leaves and pink flowers with 9 stamens. They are distributed in North America an ...
'' are found in temperate regions. Molecular data supports the
monophyly In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent comm ...
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 a ...
derivatives
hypericin Hypericin is a carbopolycyclic compound derived from bisanthene with antidepressant properties, found in various ''Hypericum'' species, and is being studied for treating cutaneous T-cell lymphoma. Opinions differ on the extent to which hypericin ...
and
pseudohypericin Pseudohypericin is an aromatic polycyclic dione that is very closely related to hypericin. It is found most commonly in the St. John's wort family of plants, namely in ''Hypericum perforatum''. In preliminary studies in animal models, pseudohyper ...
; 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 phototoxicity. ...
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 called herbalism, phytomedicine or phytotherapy) is the study of pharmacognosy and the use of medicinal plants, which are a basis of traditional medicine. Scientific evidence for the effectiveness of many herbal treatments ...
and as a
folk remedy Traditional medicine (also known as indigenous medicine or folk medicine) refers to the knowledge, skills, and practices rooted in the cultural beliefs of various societies, especially Indigenous groups, used for maintaining health and treatin ...
.


References


External links


Hypericaceae of Mongolia in FloraGREIF
{{Authority control
Hypericaceae Hypericaceae is a plant family in the order Malpighiales, 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 habitats. ...