Helianthemum
Encyclopedia
Helianthemum known as rock rose, sunroses, or rushrose, is a genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of about 110 species of 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...

 or semi-evergreen subshrub
Subshrub
A subshrub or dwarf shrub is a short woody plant. Prostrate shrub is a similar term.It is distinguished from a shrub by its ground-hugging stems and lower height, with overwintering perennial woody growth typically less than 10–20 cm tall, or by being only weakly woody and/or persisting...

s in the 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...

. They are widely distributed in the Americas
Americas
The Americas, or America , are lands in the Western hemisphere, also known as the New World. In English, the plural form the Americas is often used to refer to the landmasses of North America and South America with their associated islands and regions, while the singular form America is primarily...

, Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

, and from North Africa
North Africa
North Africa or Northern Africa is the northernmost region of the African continent, linked by the Sahara to Sub-Saharan Africa. Geopolitically, the United Nations definition of Northern Africa includes eight countries or territories; Algeria, Egypt, Libya, Morocco, South Sudan, Sudan, Tunisia, and...

 to Asia Minor
Asia Minor
Asia Minor is a geographical location at the westernmost protrusion of Asia, also called Anatolia, and corresponds to the western two thirds of the Asian part of Turkey...

 and Central Asia
Central Asia
Central Asia is a core region of the Asian continent from the Caspian Sea in the west, China in the east, Afghanistan in the south, and Russia in the north...

, with the center of diversity
Center of diversity
A center of diversity is an area that has a high degree of genetic variation for a particular species or genus of plants that can also be the center of origin for that species. The two areas often, but not always, coincide; the degree of coincidence remains the subject of debate...

 in the Mediterranean region.
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 opposite, simple oval, 1-4 cm long and 0.5-2 cm broad, varying from glossy green to tomentose grey-green. The 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 are 2-4 cm diameter, with five petals, white or yellow, occasionally tinged pink; in some species the flowers are bicoloured with a brighter yellow centre to act as a 'target' for pollinating insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...

s.
Helianthemum 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 Large Grizzled Skipper
Large Grizzled Skipper
The Large Grizzled Skipper is a species of skipper . It is distributed throughout most of continental Europe but is absent from Denmark and practically all European islands including Great Britain, Ireland, Azores, Balearic Islands, Channel Islands, Canary Islands, Crete, Cyprus, Iceland, etc.This...

 and the bucculatricid
Bucculatricidae
Bucculatricidae or is a family of moths. This small family has representatives in all parts of the world. Some authors place the group as a subfamily of the family Lyonetiidae....

 leaf-miners Bucculatrix helianthemi and Bucculatrix regaella (which both feed exclusively on Helianthemum sessiliflorum) and the Coleophora
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...

case-bearers C. bilineella, C. eupreta (feeds exclusively on H. sessiliflorum), C. ochrea (feeds exclusively on Helianthemum) and C. potentillae.
Selected species
  • Helianthemum aegyptiacum
  • Helianthemum almeriense
  • Helianthemum apenninum
    Helianthemum apenninum
    Helianthemum apenninum, the white rock-rose, is a white-flowering rock rose found in dry grassy and rocky places across large parts of Europe....

    - White Rockrose
  • Helianthemum asperum
  • Helianthemum bicknellii
  • Helianthemum canadense - Frostweed
  • Helianthemum canariense
  • Helianthemum canum
    Helianthemum canum
    Helianthemum canum, commonly called Hoary rockrose, is a low growing plant confined to rocky dry calcareous areas especially close to the sea.The plant typically has a central stock from which numerous branches radiate horizontally or ascending...

    - Hoary Rockrose
  • Helianthemum caput-felis
  • Helianthemum cinereum
  • Helianthemum corymbosum
  • Helianthemum croceum
  • Helianthemum greenei
    Helianthemum greenei
    Helianthemum greenei is a rare species of flowering plant in the rock-rose family known by the common name island rush-rose. It is endemic to the Channel Islands of California, where it grows in the chaparral of the rocky seaside slopes...

    - Island Rushrose
  • Helianthemum guerrae
    Helianthemum guerrae
    Helianthemum guerrae is a species of plant in the Cistaceae family. It is endemic to Spain. Its natural habitat is Mediterranean Matorral shrubland vegetation. It is threatened by habitat loss.-Source:...

  • Helianthemum hirsutissimum
  • Helianthemum hirtum
  • Helianthemum hymettium
  • Helianthemum jonium
  • Helianthemum kahiricum
  • Helianthemum lavandulifolium
  • Helianthemum ledifolium
  • Helianthemum leptophyllum
  • Helianthemum lipii
  • Helianthemum lunulatum
  • Helianthemum marifolium
    Helianthemum marifolium
    Helianthemum marifolium is an endangered ornamental plant in the Cistaceae family.-References:* - Javier Rodríguez-Pérez-External Links:*...

  • Helianthemum morisianum
  • Helianthemum nummularium
    Helianthemum nummularium
    Helianthemum nummularium is a species of rockrose , native to most of Europe.-Description:It is an evergreen trailing plant with loose terminal clusters of bright yellow, saucer-shaped flowers...

    - Common Rockrose
  • Helianthemum oelandicum
    Helianthemum oelandicum
    Helianthemum oelandicum is a flowering plant of the genus Helianthemum in the family Cistaceae.It is the province flower of Öland....

    - Alpine Rockrose (syn. Helianthemum montanum)
    • Helianthemum oelandicum subsp. oelandicum
    • Helianthemum oelandicum subsp. alpestre (syn. Helianthemum alpestre)
    • Helianthemum oelandicum subsp. italicum (syn. Helianthemum italicum)
    • Helianthemum oelandicum subsp. orientale (syn. Helianthemum orientale)
    • Helianthemum oelandicum subsp. rupifragum (syn. Helianthemum rupifragum)
  • Helianthemum origanifolium
  • Helianthemum pannosum
  • Helianthemum papillare
  • Helianthemum piliferum
  • Helianthemum pilosum
  • Helianthemum rossmaessler
  • Helianthemum salicifolium
  • Helianthemum sanguineum
  • Helianthemum scoparium
    Helianthemum scoparium
    Helianthemum scoparium is a species of rockrose which is endemic to California. Its common names include peak rockrose and peak rushrose, and one variety is known as Bisbee Peak rushrose. This is a small perennial shrub bearing long, smooth stems and small flowers each with five bright yellow petals...

    - Rushrose
  • Helianthemum sessiliflorum
  • Helianthemum songaricum
  • Helianthemum spartioides
  • Helianthemum squamatum
  • Helianthemum stipulatum
  • Helianthemum suffrutescens - Amador Rushrose
  • Helianthemum villosum
  • Helianthemum virgatum
  • Helianthemum viscarium
  • Helianthemum viscidulum

Cultivation and uses

Several Helianthemum species, and the numerous hybrids and cultivar
Cultivar
A cultivar'Cultivar has two meanings as explained under Formal definition. When used in reference to a taxon, the word does not apply to an individual plant but to all those plants sharing the unique characteristics that define the cultivar. is a plant or group of plants selected for desirable...

s derived from them, are widely grown as ornamental plant
Ornamental plant
Ornamental plants are plants that are grown for decorative purposes in gardens and landscape design projects, as house plants, for cut flowers and specimen display...

s, popular in rockeries. A broader range of colours is available among the cultivars, including bright salmon-pink to dark red.
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