| Dioscorea chouardii | |
|---|---|
 | |
Scientific classification  | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Monocots |
| Order: | Dioscoreales |
| Family: | Dioscoreaceae |
| Genus: | Dioscorea |
| Species: | D. chouardii |
| Binomial name | |
| Dioscorea chouardii Gaussen | |
| Synonyms | |
Borderea chouardii(Gaussen) Gaussen & Heslot | |
Dioscorea chouardii (synonym: Borderea chouardii) is a herbaceous plant in the family Dioscoreaceae. [1] It is endemic to a single cliff located in the Pyrenees of Aragon, Spain. [2]
A previously unknown species, Dioscorea chouardii was discovered in the 1950s growing in cracks in a limestone cliff in the Pyrenees Mountains in northeastern Spain. The fissures in which it lives are so inaccessible that it proved difficult to estimate the number of plants. At first it was thought that there were some 300 to 500 plants scattered across the rock face, but later, with the erection of some scaffolding and the help of binoculars and telescopes, individual plants could be monitored, and a total figure of around 9,000 plants was reached. [2]
Dioscorea chouardii was originally separated from Dioscorea , along with its close relative D. pyrenaica, in the genus Borderea on the basis of the seeds lacking the wings of most Dioscorea, although it was pointed out by 2001 that other alpine species recognised as Dioscorea in Africa and South America also had wingless seeds. [3]
Dioscorea chouardii is related to the yam and grows from a tuber hidden in the rock fissure. From this it sends out a shoot each year which withers away in the autumn. The shoot leaves a scar on the tuber, which makes it possible to estimate the age of the plant from the number of scars; the oldest plants are calculated to have lived for three hundred years, and may be contenders for being the "slowest growing plants in the world". The plant reproduces by seed, pollination having been performed by ants. When fertilised, the flower-stem bends over to bury the resulting seedhead in the crack, the seeds being released when it dries. This would limit dispersal possibilities for the plant were it not for the fact that the seeds are transported by ants, which distribute them more widely. [2]
Because most Dioscorea are strictly tropical species, this plant is considered to be what is known as a "relict species"; a remnant from the warmer temperatures of the Eocene. Dioscorea chouardii is morphologically very similar to another relict species, D. pyrenaica, which has a rather wider distribution in the Pyrenees. The former grows in vertical cracks on shaded, north-facing limestone cliffs at between 730 and 850 m (2,400 and 2,800 ft) while the latter grows on limestone screes at over 1,800 m (5,900 ft). RAPD testing strongly suggests that D chouardii is not an ecotype of D. pyrenaica and that the two taxa should be considered separate species. [3]
In 1992, under the synonym Borderea chouardii, it was designated as a 'priority species' under Annex II of the Habitats Directive in the European Community, which means areas in which it occurs could be declared Special Areas of Conservation, if these areas belong to one of the number of habitats listed in Annex I of the directive. [4] Pursuantly in the European Union, it is now protected by having seven Natura 2000 sites designated for its protection. The EU has since also officially classified this plant as 'critically endangered'. [5] Although its range is extremely small, the population of this plant seems stable, however, and there is no particular reason why climate change should affect it adversely. [2]
Dioscorea is a genus of over 600 species of flowering plants in the family Dioscoreaceae, native throughout the tropical and warm temperate regions of the world. The vast majority of the species are tropical, with only a few species extending into temperate climates. It was named by the monk Charles Plumier after the ancient Greek physician and botanist Dioscorides.
Killarney National Park, near the town of Killarney, County Kerry, was the first national park in Ireland, created when the Muckross Estate was donated to the Irish Free State in 1932. The park has since been substantially expanded and encompasses over 102.89 km2 of diverse ecology, including the Lakes of Killarney, oak and yew woodlands of international importance, and mountain peaks. It has the only red deer herd on mainland Ireland and the most extensive covering of native forest remaining in Ireland. The park is of high ecological value because of the quality, diversity, and extensiveness of many of its habitats and the wide variety of species that they accommodate, some of which are rare. The park was designated a UNESCO Biosphere Reserve in 1981. The park forms part of a Special Area of Conservation and a Special Protection Area.
Pachypodiumhabitats consist of isolated, specialized, micro–environmental niches, generally xeric, rocky, frost-free areas within parts of western Madagascar and southern Africa. Pachypodium species are often indifferent to the regional ecological, biotic zone of vegetation, a fact which explains some of Pachypodium morphology and architecture. The large scale vegetation zones are in some cases irrelevant to the micro-environments of Pachypodium, in the sense that the xeric niches may be embedded in larger mesic biomes.
Dioscorea communis or Tamus communis is a species of flowering plant in the yam family Dioscoreaceae and is commonly known as black bryony, lady's-seal or black bindweed.
Yam is the common name for some plant species in the genus Dioscorea that form edible tubers.
Dioscorea elephantipes, the elephant's foot or Hottentot bread, is a species of flowering plant in the genus Dioscorea of the family Dioscoreaceae, native to the dry interior of South Africa.
Dioscorea polystachya or Chinese yam, also called cinnamon-vine, is a species of flowering plant in the yam family. It is sometimes called Chinese potato or by its Korean name ma. It is also called huaishan in Mandarin and wàaih sāan in Cantonese.
The Habitats Directive is a directive adopted by the European Community in 1992 as a response to the Berne Convention. The European Community was reformed as the European Union the following year, but the directive is still recognised.
Dioscorea bulbifera is a species of true yam in the yam family, Dioscoreaceae. It is native to Africa, Asia and northern Australia. It is widely cultivated and has become naturalized in many regions.
Dioscorea mexicana, Mexican yam or cabeza de negro is a species of yam in the genus Dioscorea.
Dioscorea trifida is a species of flowering plant in the family Dioscoreaceae. It is a species of yam. It is native to the Caribbean and Central and South America. Its many common names include Indian yam, cush-cush, and yampee. It is called mapuey in Venezuela, inhame in Brazil, tabena and ñame in Colombia, sacha papa in Peru, and ñampi in Costa Rica.
Tacca leontopetaloides is a species of flowering plant in the yam family Dioscoreaceae. It is native to Island Southeast Asia but have been introduced as canoe plants throughout the Indo-Pacific tropics by Austronesian peoples during prehistoric times. They have become naturalized to tropical Africa, South Asia, northern Australia, and Oceania. Common names include Polynesian arrowroot, Fiji arrowroot, East Indies arrowroot, pia, and seashore bat lily.
Bupleurum kakiskalae is a species of flowering plant in the family Apiaceae. It is endemic to western Crete, an island which is part of Greece.
Antigonon leptopus is a species of perennial vine in the buckwheat family commonly known as coral vine or queen's wreath. This clambering vine is characterized by showy, usually pink flowers that can bloom throughout the year and large, heart-shaped leaves. A. leptopus is native to the Pacific and Atlantic coastal plains of Mexico, but also occurs as a roadside weed from Mexico south to Central America. It is widely introduced and invasive throughout tropical regions of the world, including in the south and eastern United States, the West Indies, South America, and the Old World tropics of Asia and Africa. This species is utilized for its edible tubers and seeds, but also for its horticultural properties as an ornamental vine in warmer parts of the world.
Dioscorea dumetorum, also known as the bitter yam, cluster yam, trifoliate yam, or three-leaved yam, is a species of flowering plant in the yam family, Dioscorea. It is native to sub-Saharan Africa and especially common in the tropical regions of West Africa, including Nigeria, Benin, and Ghana. D. dumetorum has both toxic and non-toxic varieties.
Dioscorea acuminata is a herbaceous vine in the family Dioscoreaceae, which is listed as an endangered species by the IUCN Red List. It is indigenous to the central plateau of Madagascar where it occurs on rocky substrate in a grassland-woodland mosaic habitat. There is confusion as to whether the tuber is harvested for consumption by humans as field researchers likely misidentified Dioscorea maciba as this species. However, the IUCN Red List also has an entry for D. maciba which does not cite that species as being consumed by humans.
Dioscorea alatipes is a herbaceous vine in the genus Dioscorea. It is indigenous to the Morondava Prefecture in Madagascar and is listed as an vulnerable on the IUCN Red List in 2017, having previously been listed as endangered in 2001. It has been confused with another Dioscorea species, D. bako which is a food source of the indigenous people of the region. D. alatipes is found growing in forested areas on sandy soils or on limestone substrate. This species is managed for human consumption as part of the SuLaMa Project. According to the IUCN, the species is threatened by overharvesting of the tubers as well as by the expansion of farmland in the area.
Petrocoptis pseudoviscosa, commonly known as falguera, is a species of plant in the family Caryophyllaceae. It is endemic to the Spanish province of Huesca, where it is only known from the Valle del Ésera in the Pyrenees. Its natural habitat is calcareous cliffs, crags and caves.
Dioscorea strydomiana is a critically endangered species of yam from South Africa with fewer than 250 mature individuals known to exist.