Crested coralroot | |
---|---|
Hexalectris spicata | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Monocots |
Order: | Asparagales |
Family: | Orchidaceae |
Subfamily: | Epidendroideae |
Tribe: | Epidendreae |
Subtribe: | Bletiinae |
Genus: | Hexalectris Raf. |
Type species | |
Hexalectris spicata (Walter) Barnhart |
Hexalectris (crested coralroot) [1] is a genus of the family Orchidaceae, comprising 10 known species of fully myco-heterotrophic orchids. [2] These species are found in North America, with the center of diversity in northern Mexico. [3] None of the species are particularly common. [4] Hexalectris spicata has a wide distribution and is likely the most abundant member of the genus, but is nevertheless infrequent throughout its range. [4] Other species are rare, and some, such as H. colemanii, are threatened or endangered. [5] All species that have been studied form associations with ectomycorrhizal fungi that are likely linked to surrounding trees. [6] Many Hexalectris species are found in association with oak trees (Quercus), which are ectomycorrhizal. [7]
Species accepted as of June 2014: [3]
Image | Scientific name | Distribution |
---|---|---|
Hexalectris arizonica (S.Watson) A.H.Kenn. & L.E.Watson (2010) | Arizona, New Mexico, Texas, Coahuila | |
Hexalectris brevicaulis L.O.Williams (1940) | central and southern Mexico | |
Hexalectris colemanii (Catling) A.H.Kenn. & L.E.Watson (2010) | southern Arizona | |
Hexalectris fallax M.I.Rodr. & R.González (2005) | Jalisco | |
Hexalectris grandiflora (A.Rich. & Galeotti) L.O.Williams (1944) | widespread from Texas and Chihuahua south to Oaxaca | |
Hexalectris nitida L.O.Williams (1944) | from Texas and New Mexico to southern Mexico | |
Hexalectris parviflora L.O.Williams (1940) | from Sonora to Guatemala | |
Hexalectris revoluta Correll (1941) | western Texas, southeastern New Mexico, northeastern Mexico | |
Hexalectris spicata (Walter) Barnhart (1904) | United States from Arizona east to Florida and Maryland | |
Hexalectris warnockii Ames & Correll (1943 | Arizona, New Mexico, Texas, northern Mexico | |
Orchids are plants that belong to the family Orchidaceae, a diverse and widespread group of flowering plants with blooms that are often colourful and fragrant. Orchids are cosmopolitan plants that are found in almost every habitat on Earth except glaciers. The world's richest diversity of orchid genera and species is found in the tropics.
The Russulaceae are a diverse family of fungi in the order Russulales, with roughly 1,900 known species and a worldwide distribution. They comprise the brittlegills and the milk-caps, well-known mushroom-forming fungi that include some edible species. These gilled mushrooms are characterised by the brittle flesh of their fruitbodies.
Epidendroideae is a subfamily of plants in the orchid family, Orchidaceae. Epidendroideae is larger than all the other orchid subfamilies together, comprising more than 15,000 species in 576 genera. Most epidendroid orchids are tropical epiphytes, typically with pseudobulbs. There are, however, some terrestrials such as Epipactis and even a few myco-heterotrophs, which are parasitic upon mycorrhizal fungi.
Pterospora, commonly known as pinedrops, woodland pinedrops, Albany beechdrops, or giant bird's nest is a North American genus in the subfamily Monotropoideae of the heath family, and includes only the species Pterospora andromedea. It grows as a mycoheterotroph in coniferous or mixed forests. It is widespread across much of Canada as well as the western and northeastern United States to northern Mexico. Along with Monotropa it is one of the more frequently encountered genera of the Monotropoideae.
Galeola is a genus of orchids belonging to the subfamily Vanilloideae.
Corallorhiza, the coralroot, is a genus of flowering plants in the orchid family. Except for the circumboreal C. trifida, the genus is restricted to North America.
Cypripedium acaule is a species of flowering plant in the orchid family Orchidaceae native to eastern North America. It is the provincial flower of Prince Edward Island, Canada, and the state wildflower of New Hampshire, United States.
Corallorhiza trifida, commonly known as early coralroot, northern coralroot, or yellow coralroot, is a coralroot orchid native to North America and Eurasia, with a circumboreal distribution. The species has been reported from the United States, Canada, Russia, China, Japan, Korea, India, Nepal, Kashmir, Pakistan, and almost every country in Europe.
Myco-heterotrophy is a symbiotic relationship between certain kinds of plants and fungi, in which the plant gets all or part of its food from parasitism upon fungi rather than from photosynthesis. A myco-heterotroph is the parasitic plant partner in this relationship. Myco-heterotrophy is considered a kind of cheating relationship and myco-heterotrophs are sometimes informally referred to as "mycorrhizal cheaters". This relationship is sometimes referred to as mycotrophy, though this term is also used for plants that engage in mutualistic mycorrhizal relationships.
Rhizopogon is a genus of ectomycorrhizal basidiomycetes in the family Rhizopogonaceae. Species form hypogeous sporocarps commonly referred to as "false truffles". The general morphological characters of Rhizopogon sporocarps are a simplex or duplex peridium surrounding a loculate gleba that lacks a columnella. Basidiospores are produced upon basidia that are borne within the fungal hymenium that coats the interior surface of gleba locules. The peridium is often adorned with thick mycelial cords, also known as rhizomorphs, that attach the sporocarp to the surrounding substrate. The scientific name Rhizopogon is Greek for 'root' (Rhiz-) 'beard' (-pogon) and this name was given in reference to the rhizomorphs found on sporocarps of many species.
Epipogium aphyllum, the ghost orchid is a hardy myco-heterotrophic orchid lacking chlorophyll.
Corallorhiza mertensiana, or Pacific coralroot, is a coralroot orchid native to the shady conifer forests of northwestern North America. It also goes by the common names Western coralroot and Mertens' coralroot. Corallorhiza mertensiana was previously considered a subspecies of Corallorhiza maculata but was given species rank in 1997 by Freudenstein.
Limodorum is a genus of myco-heterotrophic orchids. All species are temperate terrestrial plants and occur across much of Europe, North-West Africa, the Mediterranean Islands, and as far east as Iran. Plants have evolved away from photosynthesis and as a result their leaves are reduced to scales. There is still chlorophyll present but the plants are believed to be solely dependent on their fungal partner for nutrients. They spend most of their life underground as a short stem with fleshy roots, the unbranched inflorescence can appear in April to June if conditions are favourable.
Hexalectris arizonica, the spiked crested coralroot or Arizona crested coralroot, is a terrestrial, myco-heterotrophic orchid lacking chlorophyll and subsisting entirely on nutrients obtained from mycorrhizal fungi in the soil. It is native to Arizona, New Mexico, Texas and Coahuila. It is closely related to H. spicata and sometimes regarded as a variety of that species.
Hexalectris spicata, the spiked crested coralroot, is a terrestrial, myco-heterotrophic orchid lacking chlorophyll and subsisting entirely on nutrients obtained from mycorrhizal fungi in the soil. It is native to Arizona, New Mexico, Texas and Coahuila. It is closely related to H. arizonica and the two are sometimes considered varieties of the same species. Hexalectris spicata is endemic to the southern half of the United States from Arizona east to Florida and north to Maryland and the Ohio Valley.
Hexalectris grandiflora, the largeflower crested coralroot or giant coral-root, is a species of orchid native to Mexico from Chihuahua south to Oaxaca, as well as to western and north-central Texas. It is a myco-heterotrophic species, lacking chlorophyll and subsisting entirely on nutrients obtained by fungi in the soil.
Hexalectris revoluta, the Chisos Mountain crested coralroot, is a terrestrial, myco-heterotrophic orchid lacking chlorophyll and subsisting entirely on nutrients obtained from mycorrhizal fungi in the soil. It is closely related to H. colemanii; the two are regarded by some authors as varieties of the same species. Hexalectris revoluta is native to western Texas, southeastern New Mexico and Chihuahua.
Monotropoideae, sometimes referred to as monotropes, are a flowering plant subfamily in the family Ericaceae. Members of this subfamily are notable for their mycoheterotrophic and non-photosynthesizing or achlorophyllous characteristics.
Orchid mycorrhizae are endomycorrhizal fungi which develop symbiotic relationships with the roots and seeds of plants of the family Orchidaceae. Nearly all orchids are myco-heterotrophic at some point in their life cycle. Orchid mycorrhizae are critically important during orchid germination, as an orchid seed has virtually no energy reserve and obtains its carbon from the fungal symbiont.
Rhizopogon salebrosus is a mushroom species within the Rhizopogon sub-genus Amylopogon. R.salebrosus is a monotropoid mycorrhiza that is of vital importance to the ecology of conifer forests, especially in the Pacific Northwest region of North America. Although it is native to North America, R. salebrosus has been found in Europe and its range is generally limited to mountainous regions with sufficient precipitation. The mycoheterotrophic plant, Pterospora andromedea is often found in an obligate association with R. salebrosus in western parts of the U.S. Eastern populations of P. andromedea are typically symbiotic with another Rhizopogon sub species, R. kretzerae.