''Rheum'' is a
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
of about 60
herbaceous
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 of t ...
perennial plants
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 widel ...
in the family
Polygonaceae
The Polygonaceae are a family of flowering plants known informally as the knotweed family or smartweed—buckwheat family in the United States. The name is based on the genus ''Polygonum'', and was first used by Antoine Laurent de Jussieu in 1789 ...
. Species are native to eastern Europe, southern and eastern temperate Asia, with a few reaching into northern tropical Asia. ''Rheum'' is cultivated in Europe and North America.
[ The genus includes the vegetable ]rhubarb
Rhubarb is the fleshy, edible stalks ( petioles) of species and hybrids (culinary rhubarb) of ''Rheum'' in the family Polygonaceae, which are cooked and used for food. The whole plant – a herbaceous perennial growing from short, thick rhizo ...
. The species have large somewhat triangular shaped leaves with long, fleshy petioles. The flowers are small, greenish-white to rose-red, and grouped in large compound leafy inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...
s. A number of cultivar
A cultivar is a type of cultivated plant that people have selected for desired traits and when propagated retain those traits. Methods used to propagate cultivars include: division, root and stem cuttings, offsets, grafting, tissue culture, ...
s of rhubarb have been domesticated both as medicinal plants and for human consumption. While the leaves are slightly toxic, the stalks are used in pies and other foods for their tart flavor.
Description
''Rheum'' species are herbaceous perennials growing from fleshy roots. They have upright growing stems and mostly basal, deciduous leaves growing from short, thick rhizome
In botany and dendrology, a rhizome (; , ) is a modified subterranean plant stem that sends out roots and shoots from its nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow hori ...
s. They have persistent or deciduous ocrea. The inflorescences are terminal and panicle-like with pedicels
In botany, a pedicel is a stem that attaches a single flower to the inflorescence. Such inflorescences are described as ''pedicellate''.
Description
Pedicel refers to a structure connecting a single flower to its inflorescence. In the absenc ...
. The hermaphrodite
In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes.
Many Taxonomy (biology), taxonomic groups of animals (mostly invertebrate ...
flowers consist of a whitish green to pinkish green, hairless and campanulate
This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary o ...
(bell-shaped) perianth
The perianth (perigonium, perigon or perigone in monocots) is the non-reproductive part of the flower, and structure that forms an envelope surrounding the sexual organs, consisting of the calyx (sepals) and the corolla (petals) or tepals when ...
, composed of six tepals
A tepal is one of the outer parts of a flower (collectively the perianth). The term is used when these parts cannot easily be classified as either sepals or petals. This may be because the parts of the perianth are undifferentiated (i.e. of very ...
. The outer three tepals are narrower than the inner three and all are sepal-like in appearance. The flowers have nine (sometimes six) stamina inserted on the torus
In geometry, a torus (plural tori, colloquially donut or doughnut) is a surface of revolution generated by revolving a circle in three-dimensional space about an axis that is coplanar with the circle.
If the axis of revolution does not tou ...
at the base of the peranthium, they are free or subconnate at their base. The anthers are yellow or pinkish green, elliptic in shape. The ovary
The ovary is an organ in the female reproductive system that produces an ovum. When released, this travels down the fallopian tube into the uterus, where it may become fertilized by a sperm. There is an ovary () found on each side of the body. ...
is simple and triangular shaped with three erect or deflexed styles. The stigmas are head-like. The fruits are a three-sided achene
An achene (; ), also sometimes called akene and occasionally achenium or achenocarp, is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate (formed from one carpel) and indehiscent (they do not ope ...
with winged sides, and the seeds are albuminous with a straight or curved embryo
An embryo is an initial stage of development of a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male spe ...
.
Taxonomy
The genus ''Rheum'' was erected in 1753 by Carl Linnaeus
Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the ...
, initially for three species: '' R. rhaponticum'', '' R. rhabarbarum'' and '' R. ribes''.[ Linnaeus did not explain the origin of the genus name. ''Rheum'' is usually derived from the Greek ''rheon'',][ mentioned by ]Dioscorides
Pedanius Dioscorides ( grc-gre, Πεδάνιος Διοσκουρίδης, ; 40–90 AD), “the father of pharmacognosy”, was a Greek physician, pharmacologist, botanist, and author of ''De materia medica'' (, On Medical Material) —a 5-vol ...
as an alternative name for medicinal rhubarb; the word ''rheon'' is itself thought to be derived from the (old) Persian ''rewend''. Dioscorides calls the plant ''rha'', but mentions the Romans call it ''rha ponticum'', and it was also called ''ria'' or ''rheon''. It is theorised the Ancient Greek
Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...
word ''rha'' was derived from an ancient Scythian
The Scythians or Scyths, and sometimes also referred to as the Classical Scythians and the Pontic Scythians, were an ancient Eastern
* : "In modern scholarship the name 'Sakas' is reserved for the ancient tribes of northern and eastern Centra ...
name for the Volga River
The Volga (; russian: Во́лга, a=Ru-Волга.ogg, p=ˈvoɫɡə) is the List of rivers of Europe#Rivers of Europe by length, longest river in Europe. Situated in Russia, it flows through Central Russia to Southern Russia and into the Cas ...
in Russia, ''Rā'', near from where the plant was supposedly brought. (See .)
In 1936 Agnia Losina-Losinskaja
Agnia Sergeyevna Losina-Losinskaja () (1903–1958) was a Soviet botanist. Her family name is also transcribed as Lozina-Lozinscaia, and Lozina-Lozinskaja.
She is the author or co-author of the botanical names of at least 216 taxa, including spe ...
in Vladimir Leontyevich Komarov
Vladimir Leontyevich Komarov (russian: Влади́мир Лео́нтьевич Комаро́в; – 5 December 1945) was a Russian and Soviet botanist.
Biography
Komarov was born in 1869. He was a graduate of St. Petersburg ...
's ''Flora SSSR'' recognised 22 native species for the USSR
The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen nationa ...
, and furthermore two introduced species, one variety, and one form. The 1989 ''Plants of Central Asia'', dealing with a larger geographical remit, has Alisa E. Grabovskaya-Borodina recognising only 12 species, synonymising a great number. The ''Vascular plants of Russia and adjacent states'' of 1995 accepted 17 species for the states of the former USSR, re-recognising many of the taxa as species. In the ''Flora of China
The flora of China consists of a diverse range of plant species including over 39,000 vascular plants, 27,000 species of fungi and 3000 species of bryophytes.Wu, Z. Y., P. H. Raven & D. Y. Hong, eds. 2006. Flora of China. Vol. 22 (Poaceae). Sc ...
'' in 2003 Borodina and Bao Bojian recognise 38 species (of which 19 are endemic) in China, including a number Borodina considered synonyms in 1989.
Intergeneric relationships
''Rheum'' is placed in the family Polygonaceae
The Polygonaceae are a family of flowering plants known informally as the knotweed family or smartweed—buckwheat family in the United States. The name is based on the genus ''Polygonum'', and was first used by Antoine Laurent de Jussieu in 1789 ...
, subfamily Polygonoideae
Polygonoideae is a subfamily of plants in the family Polygonaceae. It includes a number of plants that can be highly invasive, such as Japanese knotweed, ''Reynoutria japonica'', and its hybrid with '' R. sachalinensis'', ''R.'' × ''bohemica'' ...
. Within the subfamily, it is in the tribe Rumiceae, along with the two genera ''Oxyria
Oxyria is a genus of plants in the family Polygonaceae with three accepted species . It has a circumboreal distribution.
Description
Species of ''Oxyria'' are perennial herbaceous plants or weakly shrubby. They may have rhizomes. Their stems are ...
'' and ''Rumex
The docks and sorrels, genus ''Rumex'', are a genus of about 200 species of annual, biennial, and perennial herbs in the buckwheat family, Polygonaceae.
Members of this genus are very common perennial herbs with a native almost worldwide distribu ...
''. It is most closely related to ''Rumex''.
Infrageneric classification
In the 1998 ''Flora Republicae popularis Sinicae'' A. R. Li proposed classifying the Chinese representatives of the genus into five sections
Section, Sectioning or Sectioned may refer to:
Arts, entertainment and media
* Section (music), a complete, but not independent, musical idea
* Section (typography), a subdivision, especially of a chapter, in books and documents
** Section sig ...
. These sections are distinct morphologically, but as of 2010 studies in karyotypy, pollen morphology or molecular data (chloroplast DNA) have failed to elucidate interspecific relationships.
*Sect. ''Rheum'' - Generally mid-sized species with entire, un-lobed leaves and whitish flowers.
*Sect. ''Deserticola'' (Maxim.) Losinsk. - Smallish species native to harsh desert environments.
*Sect. ''Nobilia'' A.R. Li - Large, monocarpic
Monocarpic plants are those that flower and set seeds only once, and then die.
The term is derived from Greek (''mono'', "single" + ''karpos'', "fruit" or "grain"), and was first used by Alphonse de Candolle. Other terms with the same meaning are ...
, high altitude species from the Himalayas
The Himalayas, or Himalaya (; ; ), is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the planet's highest peaks, including the very highest, Mount Everest. Over 100 ...
that create their own mini-greenhouse by having an inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...
tightly protected by transparent bract
In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves. They may be smaller, larger, or of ...
s.
*Sect. ''Palmata'' Losinsk. - The largest rhubarbs to 2m tall, with palmate
The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular o ...
, or otherwise lobed, leaves and reddish flowers.
*Sect. ''Spiciforma'' A.R. Li - Generally stemless, high altitude species with curiously hard, leathery leaves and an inflorescence with thin, spike-like panicle
A panicle is a much-branched inflorescence. (softcover ). Some authors distinguish it from a compound spike inflorescence, by requiring that the flowers (and fruit) be pedicellate (having a single stem per flower). The branches of a panicle are of ...
s. Including many dwarf species.
Losinskaja used a slightly different classification in the ''Flora SSSR'' in 1936:[
*Sect. ''Acaulia'' Losinsk.
*Sect. ''Deserticola'' (Maxim.) Losinsk.
*Sect. ''Glabrifolia'' Losinsk.
*Sect. ''Palmata'' Losinsk.
*Sect. ''Rhapontica'' Losinsk.
*Sect. ''Ribesiformia'' Losinsk.
*Sect. ''Spiciformia'' Losinsk.
]
Species
The genus is represented by about 50–60 extant species.[ The many cultivars of culinary rhubarb more usually grown for eating are recognised as ''Rheum'' × ''hybridum'' in the ]Royal Horticultural Society
The Royal Horticultural Society (RHS), founded in 1804 as the Horticultural Society of London, is the UK's leading gardening charity.
The RHS promotes horticulture through its five gardens at Wisley (Surrey), Hyde Hall (Essex), Harlow Carr (Nort ...
's list of recognised plant names. The drug rheum is prepared from the rhizomes and root
In vascular plants, the roots are the organs of a plant that are modified to provide anchorage for the plant and take in water and nutrients into the plant body, which allows plants to grow taller and faster. They are most often below the sur ...
s of another species, '' R. officinale'' or medicinal rhubarb. This species is also native to Asia, as is the turkey rhubarb, '' R. palmatum''. Another species, the Sikkim rhubarb, '' R. nobile'', is limited to the Himalayas
The Himalayas, or Himalaya (; ; ), is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the planet's highest peaks, including the very highest, Mount Everest. Over 100 ...
.
The centre of diversity
A center of origin is a geographical area where a group of organisms, either domesticated or wild, first developed its distinctive properties. They are also considered centers of diversity. Centers of origin were first identified in 1924 by N ...
for this genus is found in Central Asia
Central Asia, also known as Middle Asia, is a subregion, region of Asia that stretches from the Caspian Sea in the west to western China and Mongolia in the east, and from Afghanistan and Iran in the south to Russia in the north. It includes t ...
.
The following is a partial list of species names, some of which, according to some authorities, are considered synonyms or not fully resolved or accepted:
*'' Rheum acuminatum'' Hook.f. & Thomson
*'' Rheum alexandrae'' Batalin
*''Rheum australe
''Rheum australe'', synonym ''Rheum emodi'', is a flowering plant in the family Polygonaceae. It is commonly known as Himalayan rhubarb, Indian rhubarb and Red-veined pie plant. It is a medicinal herb used in the Indian Unani system of medici ...
'' D.Don
*'' Rheum compactum'' L.
*''Rheum cordatum
Rheum (; from Greek: ῥεῦμα ''rheuma'' 'a flowing, rheum') is a thin mucus naturally discharged from the eyes, nose, or mouth, often during sleep (cf. mucopurulent discharge).Amodio, Aime"Where Do Eye Boogers Come From?" Families.com bl ...
'' Losinsk.
*'' Rheum coreanum'' Nakai
*'' Rheum darvasicum'' V.S.Titov ex Losinsk.
*''Rheum delavayi
Rheum (; from Greek: ῥεῦμα ''rheuma'' 'a flowing, rheum') is a thin mucus naturally discharged from the eyes, nose, or mouth, often during sleep (cf. mucopurulent discharge).Amodio, Aime"Where Do Eye Boogers Come From?" Families.com blo ...
'' Franch.
*''Rheum fedtschenkoi
Rheum (; from Greek: ῥεῦμα ''rheuma'' 'a flowing, rheum') is a thin mucus naturally discharged from the eyes, nose, or mouth, often during sleep (cf. mucopurulent discharge).Amodio, Aime"Where Do Eye Boogers Come From?" Families.com blo ...
'' Maxim. ex Regel
*'' Rheum forrestii'' Diels
*''Rheum globulosum
Rheum (; from Greek: ῥεῦμα ''rheuma'' 'a flowing, rheum') is a thin mucus naturally discharged from the eyes, nose, or mouth, often during sleep (cf. mucopurulent discharge).Amodio, Aime"Where Do Eye Boogers Come From?" Families.com blo ...
'' Gage
*''Rheum hissaricum
Rheum (; from Greek language, Greek: wikt:ῥεῦμα, ῥεῦμα ''rheuma'' 'a flowing, rheum') is a thin mucus naturally discharged from the Human eye, eyes, Human nose, nose, or mouth, often during sleep (Cf., cf. mucopurulent discharge).A ...
'' Losinsk.
*'' Rheum hotaoense'' C.Y.Cheng & T.C.Kao
* ''Rheum'' × ''hybridum'' Murray
*'' Rheum inopinatum'' Prain
*'' Rheum khorasanicum'' Baradaran & Jafari
*'' Rheum kialense'' Franch.
*'' Rheum laciniatum'' Prain
*'' Rheum lhasaense'' A.J.Li & P.K.Hsiao
*'' Rheum likiangense'' Sam.
*'' Rheum lucidum'' Losinsk.
*''Rheum macrocarpum
Rheum (; from Greek: ῥεῦμα ''rheuma'' 'a flowing, rheum') is a thin mucus naturally discharged from the eyes, nose, or mouth, often during sleep (cf. mucopurulent discharge).Amodio, Aime"Where Do Eye Boogers Come From?" Families.com blo ...
'' Losinsk.
*'' Rheum maculatum'' C.Y.Cheng & T.C.Kao
*''Rheum maximowiczii
''Rheum maximowiczii'' is a large herbaceous perennial plant species in the genus ''Rheum (plant), Rheum'' (rhubarbs) from the mountains of Central Asia where it grows in Kazakhstan, eastern Uzbekistan, Tajikistan, Kyrgyzstan and northeastern Afg ...
'' Losinsk.
*''Rheum moorcroftianum
Rheum (; from Greek: ῥεῦμα ''rheuma'' 'a flowing, rheum') is a thin mucus naturally discharged from the eyes, nose, or mouth, often during sleep (cf. mucopurulent discharge).Amodio, Aime"Where Do Eye Boogers Come From?" Families.com blo ...
'' Royle
Royle is a surname. The surname may derive from Ryal, Northumberland, Ryal in Northumberland, England.
People:
* Amanda Royle (born 1962), English actress, second daughter of Derek Royle
* Adrian Royle (born 1959), retired English long distance r ...
*'' Rheum nanum'' Siev. ex Pall.
*'' Rheum neyshabourense'' Baradaran & Jafari
*''Rheum nobile
''Rheum nobile'', the Sikkim rhubarb or noble rhubarb or पदमचाल, is a giant herbaceous plant native to the Himalaya, from northeastern Afghanistan, east through northern Pakistan and India, Nepal, Sikkim (in India), Bhutan, and Tib ...
'' Hook.f. & Thomson
*'' Rheum officinale'' Baill.
*''Rheum palaestinum
''Rheum palaestinum'', the desert rhubarb, is a plant indigenous to Israel and Jordan with a highly developed system for gathering rainwater.
The plant has broad, rigid leaves, with a waxy surface, and channels cut into them that funnel any wa ...
'' Feinbrun
*''Rheum palmatum
''Rheum palmatum'' is a species of flowering plant in the knotweed family Polygonaceae. It is commonly called Chinese rhubarb, ornamental rhubarb, Turkey rhubarb or East Indian rhubarb.
''Rheum palmatum'' is a herbaceous perennial related to th ...
'' L.
*''Rheum persicum
Rheum (; from Greek: ῥεῦμα ''rheuma'' 'a flowing, rheum') is a thin mucus naturally discharged from the eyes, nose, or mouth, often during sleep (cf. mucopurulent discharge).Amodio, Aime"Where Do Eye Boogers Come From?" Families.com blo ...
'' Losinsk.
*'' Rheum platylobum'' Rech.f.
*'' Rheum przewalskyi'' Losinsk.
*'' Rheum pumilum'' Maxim.
*'' Rheum racemiferum'' Maxim.
*'' Rheum reticulatum'' Losinsk.
*''Rheum rhabarbarum
''Rheum rhabarbarum'' is a species of flowering plant in the family Polygonaceae, native to a region stretching from southern Siberia to north and central China. It has been harvested from the wild for centuries for its root, which was harvested ...
'' L.
*''Rheum rhaponticum
''Rheum rhaponticum'', the false rhubarb, rhapontic rhubarb or rhapontic, is a plant species in the genus '' Rheum'' found in the wild. It is the only ''Rheum'' species found only in Europe, and is now restricted to the Rila mountain range in sou ...
'' L.
*'' Rheum rhizostachyum'' Schrenk
*'' Rheum rhomboideum'' Losinsk.
*''Rheum ribes
''Rheum ribes'', the Syrian rhubarb or currant-fruited rhubarb, or warty-leaved rhubarb, is an edible wild rhubarb species in the genus '' Rheum''. It grows between 1000 and 4000 m on dunite rocks, among stones and slopes, and is now distribute ...
'' L.
*'' Rheum spiciforme'' Royle
*'' Rheum subacaule'' Sam.
*''Rheum sublanceolatum
Rheum (; from Greek: ῥεῦμα ''rheuma'' 'a flowing, rheum') is a thin mucus naturally discharged from the eyes, nose, or mouth, often during sleep (cf. mucopurulent discharge).Amodio, Aime"Where Do Eye Boogers Come From?" Families.com blo ...
'' C.Y.Cheng & T.C.Kao
* ''Rheum'' × ''svetlanae'' Krassovsk.
*''Rheum tanguticum
Rheum (; from Greek: ῥεῦμα ''rheuma'' 'a flowing, rheum') is a thin mucus naturally discharged from the eyes, nose, or mouth, often during sleep (cf. mucopurulent discharge).Amodio, Aime"Where Do Eye Boogers Come From?" Families.com bl ...
'' (Maxim. ex Regel) Balf.
*'' Rheum tataricum'' L.f.
*'' Rheum tibeticum'' Maxim. ex Hook.f.
*'' Rheum turkestanicum'' Janisch.
*'' Rheum uninerve'' Maxim.
*''Rheum webbianum
''Rheum webbianum'' is a species of herbaceous perennial rhubarb-relative in the family Polygonaceae from the southwestern Himalayan region, known in (Indian) English as Indian rhubarb, Gilgiti rhubarb or small Himalayan rhubarb.
Taxonomy
The s ...
'' Royle
*''Rheum wittrockii
Rheum (; from Greek: ῥεῦμα ''rheuma'' 'a flowing, rheum') is a thin mucus naturally discharged from the eyes, nose, or mouth, often during sleep (cf. mucopurulent discharge).Amodio, Aime"Where Do Eye Boogers Come From?" Families.com blo ...
'' C.E.Lundstr.
*''Rheum yunnanense
Rheum (; from Greek: ῥεῦμα ''rheuma'' 'a flowing, rheum') is a thin mucus naturally discharged from the eyes, nose, or mouth, often during sleep (cf. mucopurulent discharge).Amodio, Aime"Where Do Eye Boogers Come From?" Families.com blo ...
'' Sam.
Ecology
''Rheum'' species have been recorded as larva
A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle.
The ...
l food plants for some Lepidoptera
Lepidoptera ( ) is an order (biology), order of insects that includes butterfly, butterflies and moths (both are called lepidopterans). About 180,000 species of the Lepidoptera are described, in 126 Family (biology), families and 46 Taxonomic r ...
species such as the buff ermine, '' Spilarctia luteum'', as well as ''Arctia caja
The garden tiger moth or great tiger moth (''Arctia caja'') is a moth of the family Erebidae. ''Arctia caja'' is a northern species found in the US, Canada, and Europe. The moth prefers cold climates with temperate seasonality, as the larvae ove ...
'', '' Hydraecia micacea'' and ''Xestia baja
''Xestia baja'', the dotted clay, is a species of moth of the family Noctuidae. It is found in Europe, Turkey, northern Iran, Transcaucasia, the Caucasus, central Asia, Siberia, Mongolia, Tibet, China, Korea and Japan.
Technical description and ...
''.
''Rheum'' species are often the host plant
In biology and medicine, a host is a larger organism that harbours a smaller organism; whether a parasitic, a mutualistic, or a commensalist ''guest'' ( symbiont). The guest is typically provided with nourishment and shelter. Examples include ...
s for myrmecophilous
Myrmecophily ( , ) is the term applied to positive interspecies associations between ants and a variety of other organisms, such as plants, other arthropods, and fungi. Myrmecophily refers to mutualistic associations with ants, though in its ...
caterpillars of the butterfly genus ''Callophrys
The genus ''Callophrys'' consists of butterflies in the family Lycaenidae. It is apparently not monophyletic, but which of the taxa currently considered junior synonyms of ''Callophrys'' are valid genera remains to be determined.
The Asian and Eu ...
''; '' Callophrys titanus'' feeds on ''R. maximowiczii'' in southern Kazakhstan
Kazakhstan, officially the Republic of Kazakhstan, is a transcontinental country located mainly in Central Asia and partly in Eastern Europe. It borders Russia to the north and west, China to the east, Kyrgyzstan to the southeast, Uzbeki ...
, ''C. mystaphia'' on ''R. ribes'' in eastern Turkey
Turkey ( tr, Türkiye ), officially the Republic of Türkiye ( tr, Türkiye Cumhuriyeti, links=no ), is a list of transcontinental countries, transcontinental country located mainly on the Anatolia, Anatolian Peninsula in Western Asia, with ...
, and ''C. mystaphioides'' on ''R. persicum'' in southwest and central Iran
Iran, officially the Islamic Republic of Iran, and also called Persia, is a country located in Western Asia. It is bordered by Iraq and Turkey to the west, by Azerbaijan and Armenia to the northwest, by the Caspian Sea and Turkmeni ...
. The caterpillars of the related ''Lycaena violacea
'' Lycaena violacea '' is a small butterfly found in the Palearctic (Altai Mountains, Sayan Mountains, Transbaikalia, Mongolia, North China ) that belongs to the lycaenids or blues family.
Description
Upperside with deeper red ground colour ...
'' from southeastern Siberia
Siberia ( ; rus, Сибирь, r=Sibir', p=sʲɪˈbʲirʲ, a=Ru-Сибирь.ogg) is an extensive geographical region, constituting all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has been a part of ...
are only known to feed on ''R. rhabarbarum''.[
''R. ribes'' leaves are food for the moth '' Xylena exsoleta'' in eastern Turkey. Beetles which are specialised herbivores of this plant species in eastern Turkey are a '' Petrocladus'' sp. ]weevil
Weevils are beetles belonging to the Taxonomic rank, superfamily Curculionoidea, known for their elongated snouts. They are usually small, less than in length, and Herbivore, herbivorous. Approximately 97,000 species of weevils are known. They b ...
, the jewel beetle
Buprestidae is a family of beetles known as jewel beetles or metallic wood-boring beetles because of their glossy iridescent colors. Larvae of this family are known as flatheaded borers. The family is among the largest of the beetles, with some ...
'' Capnodis marquardti'', and the leaf beetle
The insects of the beetle family Chrysomelidae are commonly known as leaf beetles, and include over 37,000 (and probably at least 50,000) species in more than 2,500 genera, making up one of the largest and most commonly encountered of all beetle ...
''Labidostomis brevipennis
''Labidostomis'' is a genus of short-horned leaf beetles belonging to the family Chrysomelidae, subfamily Cryptocephalinae.
Species
Species within this genus include:
* ''Labidostomis amurensis'' Heyden, 1884
* ''Labidostomis asiatica'' Falderm ...
''.
In the Taldy-Bulak valley in the Talas Alatau
The Talas Ala-Too or Alataw range ( ky, Талас Ала-Тоосу, Talas Ala-Toosu; kk, Талас Алатауы, Talas Alatauy; zh, 塔拉斯阿拉套) is range of the Tian Shan mountains forming the southern and eastern border of Talas Reg ...
of Kyrgyzstan
Kyrgyzstan,, pronounced or the Kyrgyz Republic, is a landlocked country in Central Asia. Kyrgyzstan is bordered by Kazakhstan to the north, Uzbekistan to the west, Tajikistan to the south, and the People's Republic of China to the east. ...
, the emerging leaves of ''R. maximowiczii'' are an important food source for Himalayan brown bear (''Ursus arctos'' ssp. ''isabellinus'') awakening from hibernation in April.
Uses
Many ''Rheum'' species have food and medicinal uses. Some of these uses originated in Asia more than 2,000 years ago. All parts of the plant contain slightly poisonous
Poison is a chemical substance that has a detrimental effect to life. The term is used in a wide range of scientific fields and industries, where it is often specifically defined. It may also be applied colloquially or figuratively, with a broa ...
oxalic acid
Oxalic acid is an organic acid with the systematic name ethanedioic acid and formula . It is the simplest dicarboxylic acid. It is a white crystalline solid that forms a colorless solution in water. Its name comes from the fact that early inve ...
, but its concentration in the leaf stems or petioles used in food preparation is very low, and their tart flavor instead is caused by nontoxic malic acid
Malic acid is an organic compound with the molecular formula . It is a dicarboxylic acid that is made by all living organisms, contributes to the sour taste of fruits, and is used as a food additive. Malic acid has two stereoisomeric forms ...
. The plants also produce other compounds, including citric acid
Citric acid is an organic compound with the chemical formula HOC(CO2H)(CH2CO2H)2. It is a colorless weak organic acid. It occurs naturally in citrus fruits. In biochemistry, it is an intermediate in the citric acid cycle, which occurs in t ...
and anthraquinone
Anthraquinone, also called anthracenedione or dioxoanthracene, is an aromatic organic compound with formula . Isomers include various quinone derivatives. The term anthraquinone however refers to the isomer, 9,10-anthraquinone (IUPAC: 9,10-dioxo ...
glycoside
In chemistry, a glycoside is a molecule in which a sugar is bound to another functional group via a glycosidic bond. Glycosides play numerous important roles in living organisms. Many plants store chemicals in the form of inactive glycosides. ...
s, and the raw or cooked leaf blades are poisonous to humans and livestock if consumed in large enough amounts. Plants in cultivation are propagated by cutting up the crowns of larger plants and by seeds.
Some species are grown for their ornamental qualities, including ''R. acuminatum'', ''R. alexandrae'', ''R. australe'', ''R. kialense'', ''R. palmatum'', ''R. rhabarbarum'' and ''R. ribes''.
The roots of ''R. macrocarpum'' are exploited in the Tian-Shan
The Tian Shan,, , otk, 𐰴𐰣 𐱅𐰭𐰼𐰃, , tr, Tanrı Dağı, mn, Тэнгэр уул, , ug, تەڭرىتاغ, , , kk, Тәңіртауы / Алатау, , , ky, Теңир-Тоо / Ала-Тоо, , , uz, Tyan-Shan / Tangritog‘ ...
to make a dye.[
]
References
{{Taxonbar, from=Q7217716
Polygonaceae genera