Cistus
Encyclopedia
Cistus is a genus of flowering plant
s in the rockrose family
Cistaceae
, containing about 20 species (Ellul et al. 2002). They are perennial
shrub
s found on dry or rocky soils throughout the Mediterranean region, from Morocco
and Portugal
through to the Middle East
, and also on the Canary Islands
. The leaves
are evergreen
, opposite, simple, usually slightly rough-surfaced, 2–8 cm long; in a few species (notably C. ladanifer), the leaves are coated with a highly aromatic resin
called labdanum
. They have showy 5-petaled flower
s ranging from white to purple and dark pink, in a few species with a conspicuous dark red spot at the base of each petal., and together with its many hybrids and cultivars is commonly encountered as a garden flower.
The common name rockrose is applied to the species, a name also shared by the related genera Halimium
, Helianthemum
and Tuberaria
, all in the family Cistaceae.
l associations with truffles (Tuber) and are thus able to thrive on poor sandy soils or rocks. Cistus ladanifer has been found to have mycorrhizal associations with Boletus edulis
, Boletus rhodoxanthus
, and Laccaria laccata
.
Cistus are the only host of Cytinus hypocistis
, a small parasitic plant that lives on the roots and is noticeable only for a short period of time when in flower. The presence of the parasite does not seem to hurt the host population.
Cistus species are used as food plants by the larva
e of some Lepidoptera
species including Coleophora confluella
and Coleophora helianthemella
, the latter recorded on Cistus monspeliensis.
form a cohesive and the most derived clade within Cistaceae
. Phylogenetic analyses delineated two major lineages within Cistus, a purple-flowered clade and a white-flowered clade, excepting Cistus parviflorus. Further analysis of morphological characters show that C. parviflorus has the purple flowers of the purple-flowered clade, but the sessile stigmas
of the white-flowered clade, indicating a potential instance of speciation
via hybridization.
The white-flowered Cistus lineage was further found to consist of two groups with asymmetric characteristics, which together with ecological evidence, supports the theory of adaptive radiation
within this lineage.
. The hardiest of the species is C. laurifolius, which survived the hard frost at Royal Botanical Gardens at Kew in 1895 that eliminated all the cistuses save this and two white-flowered natural hybrids, C. × corbariensis, already grown by John Tradescant the Elder
, and C. × loretii, a 19th-century introduction.
Cultivars include:
viruses (influenza
) significantly inhibits in vitro without resistance. Possibly, this research to a new treatment for the flu virus, including bird flu.
The effectiveness in humans, however, with scientific studies have not yet been established.
Flowering plant
The flowering plants , also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants. Angiosperms are seed-producing plants like the gymnosperms and can be distinguished from the gymnosperms by a series of synapomorphies...
s in the rockrose family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Cistaceae
Cistaceae
The Cistaceae is a small family of plants known for its beautiful shrubs, which are profusely covered by flowers at the time of blossom...
, containing about 20 species (Ellul et al. 2002). They are perennial
Perennial plant
A perennial plant or simply perennial is a plant that lives for more than two years. The term is often used to differentiate a plant from shorter lived annuals and biennials. The term is sometimes misused by commercial gardeners or horticulturalists to describe only herbaceous perennials...
shrub
Shrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...
s found on dry or rocky soils throughout the Mediterranean region, from Morocco
Morocco
Morocco , officially the Kingdom of Morocco , is a country located in North Africa. It has a population of more than 32 million and an area of 710,850 km², and also primarily administers the disputed region of the Western Sahara...
and Portugal
Portugal
Portugal , officially the Portuguese Republic is a country situated in southwestern Europe on the Iberian Peninsula. Portugal is the westernmost country of Europe, and is bordered by the Atlantic Ocean to the West and South and by Spain to the North and East. The Atlantic archipelagos of the...
through to the Middle East
Middle East
The Middle East is a region that encompasses Western Asia and Northern Africa. It is often used as a synonym for Near East, in opposition to Far East...
, and also on the Canary Islands
Canary Islands
The Canary Islands , also known as the Canaries , is a Spanish archipelago located just off the northwest coast of mainland Africa, 100 km west of the border between Morocco and the Western Sahara. The Canaries are a Spanish autonomous community and an outermost region of the European Union...
. The leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
are evergreen
Evergreen
In botany, an evergreen plant is a plant that has leaves in all seasons. This contrasts with deciduous plants, which completely lose their foliage during the winter or dry season.There are many different kinds of evergreen plants, both trees and shrubs...
, opposite, simple, usually slightly rough-surfaced, 2–8 cm long; in a few species (notably C. ladanifer), the leaves are coated with a highly aromatic resin
Resin
Resin in the most specific use of the term is a hydrocarbon secretion of many plants, particularly coniferous trees. Resins are valued for their chemical properties and associated uses, such as the production of varnishes, adhesives, and food glazing agents; as an important source of raw materials...
called labdanum
Labdanum
Labdanum is a sticky brown resin obtained from the shrubs Cistus ladanifer and Cistus creticus , species of rockrose. It has a long history of use in herbal medicine and as a perfume ingredient.-History:...
. They have showy 5-petaled flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s ranging from white to purple and dark pink, in a few species with a conspicuous dark red spot at the base of each petal., and together with its many hybrids and cultivars is commonly encountered as a garden flower.
The common name rockrose is applied to the species, a name also shared by the related genera Halimium
Halimium
Halimium is a genus of 12 species of evergreen or semi-evergreen subshrubs in the family Cistaceae, closely related to Helianthemum...
, Helianthemum
Helianthemum
Helianthemum , known as rock rose, sunroses, or rushrose, is a genus of about 110 species of evergreen or semi-evergreen subshrubs in the family Cistaceae...
and Tuberaria
Tuberaria
Tuberaria is a genus of about 112 species of annual or perennial plants in the rockrose family Cistaceae, native to western and southern Europe. They occur on dry, stony sites, often close to the sea....
, all in the family Cistaceae.
Species
There are about 20 species in the genus:
|
Cistus monspeliensis Cistus monspeliensis is a species of rockrose known by the common name Montpelier cistus. It is native to southern Europe and northern Africa, in the Mediterranean forests, woodlands, and scrub ecosystems of matorral—maquis shrublands.-Description:... – Montpelier Cistus Cistus salviifolius Cistus salviifolius, common name Sage-leaved Rock Rose or Salvia Cistus, is a perennial ligneous plant of Cistaceae family.-Etymology:... – Salvia Cistus |
Ecology
They are thermophilous plants, which require open, sunny places. This plant genus is peculiar in that it has developed a range of specific adaptations to resist summer drought and frequent disturbance events, such as fire and grazing. In addition, it can form both ectomycorrhizas and arbuscular mycorrhizas. More than 200 ectomycorrhiza-forming fungal species belonging to 40 genera have been reported so far to be associated with Cistus. As with many other Cistaceae, the species of Cistus have the ability to form mycorrhizaMycorrhiza
A mycorrhiza is a symbiotic association between a fungus and the roots of a vascular plant....
l associations with truffles (Tuber) and are thus able to thrive on poor sandy soils or rocks. Cistus ladanifer has been found to have mycorrhizal associations with Boletus edulis
Boletus edulis
Boletus edulis, commonly known as penny bun, porcino or cep, is a basidiomycete fungus, and the type species of the genus Boletus. Widely distributed in the Northern Hemisphere across Europe, Asia, and North America, it does not occur naturally in the Southern Hemisphere, although it has been...
, Boletus rhodoxanthus
Boletus rhodoxanthus
Boletus rhodoxanthus is a fungus of the genus Boletus. It is a rare, inedible bolete found in warm deciduous forests of southern Europe mainly under oak and beech, on chalky soil.-Description:...
, and Laccaria laccata
Laccaria laccata
Laccaria laccata, commonly known as the deceiver, or waxy laccaria, is a white-spored species of small edible mushroom found throughout North America and Europe. It is a highly variable mushroom , and can look quite washed out, colorless and drab, but when younger it often assumes red, pinkish...
.
Cistus are the only host of Cytinus hypocistis
Cytinus
Cytinus is a genus of parasitic flowering plants. Species in this genus do not produce chlorophyll, but rely fully on its host plant. Cytinus only parasitizes Cistus and Halimium, two genera of plants in the Cistaceae family....
, a small parasitic plant that lives on the roots and is noticeable only for a short period of time when in flower. The presence of the parasite does not seem to hurt the host population.
Cistus species are used as food plants by the larva
Larva
A larva 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...
e of some Lepidoptera
Lepidoptera
Lepidoptera is a large order of insects that includes moths and butterflies . It is one of the most widespread and widely recognizable insect orders in the world, encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies...
species including Coleophora confluella
Coleophora
Coleophora is a very large genus of moths of the family Coleophoridae. It contains some 1,350 described species. The genus is represented on all continents, but the majority are found in the Nearctic and Palaearctic regions...
and Coleophora helianthemella
Coleophora
Coleophora is a very large genus of moths of the family Coleophoridae. It contains some 1,350 described species. The genus is represented on all continents, but the majority are found in the Nearctic and Palaearctic regions...
, the latter recorded on Cistus monspeliensis.
Systematics
Cistus and HalimiumHalimium
Halimium is a genus of 12 species of evergreen or semi-evergreen subshrubs in the family Cistaceae, closely related to Helianthemum...
form a cohesive and the most derived clade within Cistaceae
Cistaceae
The Cistaceae is a small family of plants known for its beautiful shrubs, which are profusely covered by flowers at the time of blossom...
. Phylogenetic analyses delineated two major lineages within Cistus, a purple-flowered clade and a white-flowered clade, excepting Cistus parviflorus. Further analysis of morphological characters show that C. parviflorus has the purple flowers of the purple-flowered clade, but the sessile stigmas
Gynoecium
Gynoecium is most commonly used as a collective term for all carpels in a flower. A carpel is the ovule and seed producing reproductive organ in flowering plants. Carpels are derived from ovule-bearing leaves which evolved to form a closed structure containing the ovules...
of the white-flowered clade, indicating a potential instance of speciation
Speciation
Speciation is the evolutionary process by which new biological species arise. The biologist Orator F. Cook seems to have been the first to coin the term 'speciation' for the splitting of lineages or 'cladogenesis,' as opposed to 'anagenesis' or 'phyletic evolution' occurring within lineages...
via hybridization.
The white-flowered Cistus lineage was further found to consist of two groups with asymmetric characteristics, which together with ecological evidence, supports the theory of adaptive radiation
Adaptive radiation
In evolutionary biology, adaptive radiation is the evolution of ecological and phenotypic diversity within a rapidly multiplying lineage. Starting with a recent single ancestor, this process results in the speciation and phenotypic adaptation of an array of species exhibiting different...
within this lineage.
Cultivation
Cistuses are among the defining plants of sunny gardens with a nearly frost-free Mediterranean climateMediterranean climate
A Mediterranean climate is the climate typical of most of the lands in the Mediterranean Basin, and is a particular variety of subtropical climate...
. The hardiest of the species is C. laurifolius, which survived the hard frost at Royal Botanical Gardens at Kew in 1895 that eliminated all the cistuses save this and two white-flowered natural hybrids, C. × corbariensis, already grown by John Tradescant the Elder
John Tradescant the elder
John Tradescant the elder , father of John Tradescant the younger, was an English naturalist, gardener, collector and traveller, probably born in Suffolk, England...
, and C. × loretii, a 19th-century introduction.
Cultivars include:
- Cistus × dansereaui - prostrate form of this hybrid is often cultivated
- Cistus × florentinus - white flowers
- Cistus × hybridus - pink buds, white flowers
- Cistus × purpureusCistus × purpureusCistus × purpureus, commonly known as Orchid Rockrose, is one of the most commonly cultivated varieties of rockrose. The pink flowers, which appear in summer, have petals with a dark blotch towards the centre....
- pink petals with dark blotches near centre - Cistus × skanbergii - small pink flowers
- Cistus 'Grayswood Pink' - a selected from of Cistus parviflorus
- Cistus 'Paladin' - large white flowers, dark green leaves
- Cistus 'Peggy Sammons' - pink flowers, grey-green leaves
Medical use
Several research groups have a special extract of the rockrose (C. incanus ssp. Tauricus) can show that the propagation of the virus fluInfluenza
Influenza, commonly referred to as the flu, is an infectious disease caused by RNA viruses of the family Orthomyxoviridae , that affects birds and mammals...
viruses (influenza
Influenza
Influenza, commonly referred to as the flu, is an infectious disease caused by RNA viruses of the family Orthomyxoviridae , that affects birds and mammals...
) significantly inhibits in vitro without resistance. Possibly, this research to a new treatment for the flu virus, including bird flu.
The effectiveness in humans, however, with scientific studies have not yet been established.
External links
- Ellul P., M. Boscaiu, O. Vicente, V. Moreno, J. A. Rossello (2002). Intra- and Interspecific Variation in DNA Content in Cistus (Cistaceae). Annals of Botany 90 (3): 345-351 (available online: full text (html) | full text (pdf)).
- Page, R. G. The Cistus & Halimium Website