Saxifraga is the largest genus in the family Saxifragaceae, containing about 473 species of holarcticperennial plants, known as saxifrages[1][2] or rockfoils.[3] The Latin word saxifraga means literally "stone-breaker", from Latinsaxum ("rock" or "stone") + frangere ("to break"). It is usually thought to indicate a medicinal use for treatment of urinary calculi (known as kidney or bladder stones), rather than breaking rocks apart.[2][4]
The inflorescence or single flower clusters rise above the main plant body on naked stalks. The small actinomorphichermaphrodite flowers have five petals and sepals and are usually white, but red to yellow in some species. Stamens, usually 10, rarely 8, insert at the junction of the floral tube and ovary wall, with filaments subulate or clavate. As in other primitive eudicots, some of the 5 or 10 stamens may appear petal-like.[citation needed] and it lives in tundral ecosystems.[5][8][6]
Taxonomy
A genus of about 473 species.[1] The former monotypic genus Saxifragella has been submersed within Saxifraga, the largest genus in Saxifragaceae, as Saxifraga bicuspidata.[9][5] Also the genus Saxifragopsis (strawberry saxifrage) was previously included in Saxifraga.[10]
Subdivision
Based on morphological criteria, up to 15 sections were recognised.[11] Subsequent molecular phylogenetic studies reduced this to 13 sections with 9 subsections. The former sections Micranthes and Merkianae are more closely related to the Boykinia and Heucheraclades.[12] Modern floras separate these groups as the genus Micranthes.[13][6]
Pepper-saxifrage, Silaum silaus. The name "silaum" comes from the Latin word sil, which means yellow ochre. This refers to the sulphurous yellow colour of the flowers.[17]
Some plants refer to Saxifraga in their generic names or specific epithets, either because they are also "rock-breaking" or because they resemble members of the saxifrage genus:[citation needed]
Saxifrages are typical inhabitants of Arctic–alpineecosystems, and are hardly ever found outside the temperate parts of the Northern Hemisphere; most members of this genus are found in subarctic climates. A good number of species grow in glacial habitats, such as S. biflora which can be found some 4,000m (13,000ft) above sea level in the Alps, or the East Greenland saxifrage (S. nathorstii). The genus is also abundant in the Eastern and Western Himalayan alpine shrub and meadows. Though the archetypal saxifrage is a small plant huddling between rocks high up on a mountain, many species do not occur in such a habitat and are larger (though still rather delicate) plants found on wet meadows.
Charles Darwin – erroneously believing Saxifraga to be allied to the sundew family (Droseraceae) – suspected the sticky-leaved round-leaved saxifrage (S. rotundifolia), rue-leaved saxifrage (S. tridactylites) and Pyrenean saxifrage (S. umbrosa) to be protocarnivorous plants, and conducted some experiments whose results supported his observations,[19] but the matter has apparently not been studied since his time.
Numerous species and cultivars of saxifrage are cultivated as ornamental garden plants, valued particularly as groundcover or as cushion plants in rock gardens and alpine gardens. Many require alkaline or neutral soil to thrive.[7]
The leaves of some saxifrage species, such as creeping saxifrage (S. stolonifera) and S. pensylvanica,[51] are edible. The former is a food in Korea[52] and Japan.[citation needed] The flowers of purple saxifrage (S. oppositifolia) are eaten in Nunavut, Canada and the leaves and stems brewed as a tea.[53]
Species are also used in traditional medicine, such as creeping saxifrage in East Asia[54] and round-leaved saxifrage (S. rotundifolia) in Europe.[55]
Two species—purple saxifrage and creeping saxifrage—are popular floral emblems. They are official flowers for:
↑ Charles Darwin (1875). "Drosophyllum – Roridula – Byblis – glandular hairs of other plants – concluding remarks on the Droseraceae". Insectivorous Plants (1sted.). London: J. Murray. pp.332–367.
↑ Niering, William A.; Olmstead, Nancy C. (1985) [1979]. The Audubon Society Field Guide to North American Wildflowers, Eastern Region. Knopf. p.780. ISBN0-394-50432-1.
↑ Ji-xian Guo, Ki Sung Chung, Paul Pui-hay But, Takeatsu Kimura (1996). International Collation Of Traditional And Folk Medicine, Vol 2: Northeast Asia Part 2. World Scientific Publishing Company. p.65.{{cite book}}: CS1 maint: multiple names: authors list (link)
↑ Pieroni, Andrea; Quave, Cassandra L., eds. (2014). Ethnobotany and Biocultural Diversities in the Balkans. New York: Springer.
This page is based on this Wikipedia article Text is available under the CC BY-SA 4.0 license; additional terms may apply. Images, videos and audio are available under their respective licenses.
