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30-481: 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. The overall morphology of these plants is highly reduced compared to other members of the Ericaceae, which are practically all subshrubs , shrubs , or trees . By contrast,

60-1832: A molecular phylogeny of plants placed the flowering plants in their evolutionary context: Bryophytes [REDACTED] Lycophytes [REDACTED] Ferns [REDACTED] [REDACTED] [REDACTED] The main groups of living angiosperms are: Amborellales [REDACTED] 1 sp. New Caledonia shrub Nymphaeales [REDACTED] c. 80 spp. water lilies & allies Austrobaileyales [REDACTED] c. 100 spp. woody plants Magnoliids [REDACTED] c. 10,000 spp. 3-part flowers, 1-pore pollen, usu. branch-veined leaves Chloranthales [REDACTED] 77 spp. Woody, apetalous Monocots [REDACTED] c. 70,000 spp. 3-part flowers, 1 cotyledon , 1-pore pollen, usu. parallel-veined leaves   Ceratophyllales [REDACTED] c. 6 spp. aquatic plants Eudicots [REDACTED] c. 175,000 spp. 4- or 5-part flowers, 3-pore pollen, usu. branch-veined leaves Amborellales Melikyan, Bobrov & Zaytzeva 1999 Nymphaeales Salisbury ex von Berchtold & Presl 1820 Austrobaileyales Takhtajan ex Reveal 1992 Chloranthales Mart. 1835 Canellales Cronquist 1957 Piperales von Berchtold & Presl 1820 Magnoliales de Jussieu ex von Berchtold & Presl 1820 Laurales de Jussieu ex von Berchtold & Presl 1820 Acorales Link 1835 Alismatales Brown ex von Berchtold & Presl 1820 Petrosaviales Takhtajan 1997 Dioscoreales Brown 1835 Pandanales Brown ex von Berchtold & Presl 1820 Liliales Perleb 1826 Asparagales Link 1829 Arecales Bromhead 1840 Poales Small 1903 Zingiberales Grisebach 1854 Commelinales de Mirbel ex von Berchtold & Presl 1820 Dahlgren system Dahlgren ranked

90-619: A spike , and in Monotropa , the inflorescence can take the form of a solitary flower . Notably, the shoots are achlorophyllous , in keeping with the mycoheterotrophic and non- photosynthetic nature of the plant, and the plants have a striking and distinctive appearance, with coloration ranging from pure white to pastel tones to very bright yellow or red. (If the Pyroleae are included, many of these species are partially photosythentic, and have green vegetative tissue, though leaves are usually reduced to

120-442: A woody stem ), grasses and grass-like plants, a vast majority of broad-leaved trees , shrubs and vines , and most aquatic plants . Angiosperms are distinguished from the other major seed plant clade, the gymnosperms , by having flowers , xylem consisting of vessel elements instead of tracheids , endosperm within their seeds, and fruits that completely envelop the seeds. The ancestors of flowering plants diverged from

150-477: A basal rosette .) The emerging shoots may be erect or nodding, with erect or pendulous flowers, which may become more erect as the plant matures. The flowers themselves, in common with other members of the Ericaceae, have corollas that are generally bell- or cup-shaped, though the petals themselves may or may not be fused. However, the Monotropoideae lack the poricidal anthers that are characteristic of

180-466: A continuum, and that plant-fungus symbioses with a clearly mycorrhizal root anatomy can include exploitative relationships.) The Monotropoideae are adapted for pollination by bumble bees ( Bombus ), including specialized buzz pollination in a few genera. In some genera (such as Monotropa ), some degree of self-pollination has been observed in addition to bumble bee pollination. Hummingbirds have also been observed visiting Sarcodes , though it

210-462: A distinct plant family by Thomas Nuttall in 1818, when he united the Linnean genus Monotropa with his newly authored genus and species Pterospora andromedea as the family Monotropeae (changed by later authors to Monotropaceae when modern rules of naming plant taxa were developed). David Don was the first to recognize this group as a tribe within the Ericaceae, later raised to subfamily status as

240-610: A total of 64 angiosperm orders and 416 families. The diversity of flowering plants is not evenly distributed. Nearly all species belong to the eudicot (75%), monocot (23%), and magnoliid (2%) clades. The remaining five clades contain a little over 250 species in total; i.e. less than 0.1% of flowering plant diversity, divided among nine families. The 25 most species-rich of 443 families, containing over 166,000 species between them in their APG circumscriptions, are: The botanical term "angiosperm", from Greek words angeíon ( ἀγγεῖον 'bottle, vessel') and spérma ( σπέρμα 'seed'),

270-858: Is starting to impact plants and is likely to cause many species to become extinct by 2100. Angiosperms are terrestrial vascular plants; like the gymnosperms, they have roots , stems , leaves , and seeds . They differ from other seed plants in several ways. The largest angiosperms are Eucalyptus gum trees of Australia, and Shorea faguetiana , dipterocarp rainforest trees of Southeast Asia, both of which can reach almost 100 metres (330 ft) in height. The smallest are Wolffia duckweeds which float on freshwater, each plant less than 2 millimetres (0.08 in) across. Considering their method of obtaining energy, some 99% of flowering plants are photosynthetic autotrophs , deriving their energy from sunlight and using it to create molecules such as sugars . The remainder are parasitic , whether on fungi like

300-480: Is acidic to varying degrees. Distribution is through much of the temperate Northern Hemisphere , though ranging into the subarctic and montane tropical regions as well. Distribution is limited by available moisture (Monotropoideae species have limited ability to survive long enough to set seed during seasonal dry periods), and by the distribution of conifer genera that are hosts of the specific host fungi these plants parasitize. The distribution of Monotropa

330-478: Is also primarily bumble bee-pollinated. Several floral scent compounds of Monotropastrum humile , linalool , α-terpineol , and geraniol , have been demonstrated to be bumble bee attractants. Monotropoids occur in coniferous or mixed coniferous forests , often in areas with a heavy, closed overstory with low light availability . They occur in boggy areas, in deep humusy soils, and even relatively dry slopes. The soil pH in locations in which they occur

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360-409: Is generally very specific in terms of its fungal hosts, ranging from single families of fungi, to a few closely related species. The morphology of the root and the root-level fungal symbiont is distinctive and referred to as monotropoid mycorrhiza . (Although mycorrhizas are generally considered to be mutualistic relationships, it is generally recognized that mutualism and parasitism exist on

390-723: Is responsible for the majority of the range of this subfamily, with other genera not having the same global distribution. The center of biodiversity for this subfamily is found in temperate western North America , along the northern and central California and Pacific Northwest coast and montane areas as far east as the Sierra Nevada-Cascade cordillera . Seven of the 10 genera usually recognized as members of this subfamily (excluding Pyroleae) occur there, with 6 of these occurring only in that region. Flowering plant Basal angiosperms Core angiosperms Flowering plants are plants that bear flowers and fruits , and form

420-485: The Alismatales grow in marine environments, spreading with rhizomes that grow through the mud in sheltered coastal waters. Some specialised angiosperms are able to flourish in extremely acid or alkaline habitats. The sundews , many of which live in nutrient-poor acid bogs , are carnivorous plants , able to derive nutrients such as nitrate from the bodies of trapped insects. Other flowers such as Gentiana verna ,

450-580: The clade Angiospermae ( / ˌ æ n dʒ i ə ˈ s p ər m iː / ). The term 'angiosperm' is derived from the Greek words ἀγγεῖον / angeion ('container, vessel') and σπέρμα / sperma ('seed'), meaning that the seeds are enclosed within a fruit. The group was formerly called Magnoliophyta . Angiosperms are by far the most diverse group of land plants with 64 orders , 416 families , approximately 13,000 known genera and 300,000 known species . They include all forbs (flowering plants without

480-453: The dicotyledons and monocotyledons as subclasses of the class of flowering plants ( angiosperms ) and further divided them into superorders . Originally (1975) he used the suffix -anae , as did Cronquist , to designate these, but in 1980 changed this to -florae in accordance with Thorne . In the 1989 revision, published by his wife, the alternate names Magnoliidae and Liliidae were dropped in favour of Dicotyledon and Monocotyledon, and

510-460: The orchids for part or all of their life-cycle, or on other plants , either wholly like the broomrapes, Orobanche , or partially like the witchweeds, Striga . In terms of their environment, flowering plants are cosmopolitan, occupying a wide range of habitats on land, in fresh water and in the sea. On land, they are the dominant plant group in every habitat except for frigid moss-lichen tundra and coniferous forest . The seagrasses in

540-883: The "Big Five" extinction events in Earth's history, only the Cretaceous–Paleogene extinction event had occurred while angiosperms dominated plant life on the planet. Today, the Holocene extinction affects all kingdoms of complex life on Earth, and conservation measures are necessary to protect plants in their habitats in the wild ( in situ ), or failing that, ex situ in seed banks or artificial habitats like botanic gardens . Otherwise, around 40% of plant species may become extinct due to human actions such as habitat destruction , introduction of invasive species , unsustainable logging , land clearing and overharvesting of medicinal or ornamental plants . Further, climate change

570-731: The Ericaceae. Contemporary molecular phylogenetics has clearly established the Monotropoideae as a group within the larger Ericaceae, though many of the details of relationships between the Monotropoideae and the rest of the Ericaceae are still (as of 2015) a topic of active research, particularly the question of whether or not the Pyroleae and the rest of the Monotropeae form a single monophyletic group. The species in this subfamily are all mycoheterotrophic , relying on fungal hosts for their carbon nutrition. The fungi parasitized by these plants are ectomycorrhizal species of fungi, that are part of

600-401: The Monotropoideae are all herbaceous perennials , in which an annual shoot reemerges seasonally (in spring or early summer, depending on climate) from a perennial root . The shoot can be characterized as a single inflorescence or cluster of inflorescences, and is generally a raceme with one to many flowers per axis, though occasionally the raceme may be so reduced as to appear similar to

630-428: The Monotropoideae by Asa Gray in 1878. (However, George Arnott Walker-Arnott was the first to validly publish that name, as a subfamily of Monotropaceae, in 1832, hence, Arnott is cited as author of the name.) Other classifications have included Monotropoideae as a subfamily of Hypopityaceae, by August W. Eichler (1875), and as a subfamily of Pyrolaceae by Carl Georg Oscar Drude (1889); both classifications united

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660-484: The Russulaceae . Hence, these plants act as direct parasites of these fungi, and also indirectly, act as an epiparasite of conifers and the larger shared mycorrhizal network. Monotropoideae species can generally be described as full, obligate mycoheterotrophs, though if the Pyroleae are treated as part of the Monotropoideae, include partially mycoheterotrophic ( mixtotrophic ) members as well. The parasitism by these plants

690-547: The common ancestor of all living gymnosperms before the end of the Carboniferous , over 300 million years ago. In the Cretaceous , angiosperms diversified explosively , becoming the dominant group of plants across the planet. Agriculture is almost entirely dependent on angiosperms, and a small number of flowering plant families supply nearly all plant-based food and livestock feed. Rice , maize and wheat provide half of

720-635: The flowering plants as an unranked clade without a formal Latin name (angiosperms). A formal classification was published alongside the 2009 revision in which the flowering plants rank as the subclass Magnoliidae. From 1998, the Angiosperm Phylogeny Group (APG) has reclassified the angiosperms, with updates in the APG II system in 2003, the APG III system in 2009, and the APG IV system in 2016. In 2019,

750-521: The majority of the Ericaceae. (The Pyroleae do have poricidal anthers, however.) Pollen grains are released as a monad, in contrast to the majority of the Ericaceae, which release pollen grains in tetrad groups. (The Pyroleae variously release pollen as monads, tetrads, or polyads.) Fruits are dry loculicidal dehiscent (or sometimes indehiscent) capsule or a berry . Seeds are highly reduced dust seeds . The shoot may or may not be persistent after seed dispersal . The monotropes were first described as

780-518: The manner of vines or lianas . The number of species of flowering plants is estimated to be in the range of 250,000 to 400,000. This compares to around 12,000 species of moss and 11,000 species of pteridophytes . The APG system seeks to determine the number of families , mostly by molecular phylogenetics . In the 2009 APG III there were 415 families. The 2016 APG IV added five new orders (Boraginales, Dilleniales, Icacinales, Metteniusales and Vahliales), along with some new families, for

810-412: The monotropes with the pyrolids in a single group. Over the next century, authors have variously treated this group as a distinct family or as a subfamily of the Ericaceae, though the trend from Margaret W. Henderson (1919) onward was toward the latter subfamily classification, albeit, the influential Cronquist and Dahlgren systems continued to treat the group as the family Monotropaceae, separate from

840-568: The spring gentian, are adapted to the alkaline conditions found on calcium -rich chalk and limestone , which give rise to often dry topographies such as limestone pavement . As for their growth habit , the flowering plants range from small, soft herbaceous plants , often living as annuals or biennials that set seed and die after one growing season, to large perennial woody trees that may live for many centuries and grow to many metres in height. Some species grow tall without being self-supporting like trees by climbing on other plants in

870-554: The world's staple calorie intake, and all three plants are cereals from the Poaceae family (colloquially known as grasses). Other families provide important industrial plant products such as wood , paper and cotton , and supply numerous ingredients for beverages , sugar production , traditional medicine and modern pharmaceuticals . Flowering plants are also commonly grown for decorative purposes , with certain flowers playing significant cultural roles in many societies. Out of

900-483: Was coined in the form "Angiospermae" by Paul Hermann in 1690, including only flowering plants whose seeds were enclosed in capsules. The term angiosperm fundamentally changed in meaning in 1827 with Robert Brown , when angiosperm came to mean a seed plant with enclosed ovules. In 1851, with Wilhelm Hofmeister 's work on embryo-sacs, Angiosperm came to have its modern meaning of all the flowering plants including Dicotyledons and Monocotyledons. The APG system treats

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