Apodanthaceae | |
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Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Rosids |
Order: | Cucurbitales |
Family: | Apodanthaceae Tiegh. ex Takht. |
Genera | |
The family Apodanthaceae comprises about 10 species [1] of endoparasitic herbs. They live in the branches or stems of their hosts (as filaments similar to a fungal mycelium), emerging only to flower and fruit. The plants produce no green parts and do not carry out any photosynthesis (that is, they are holoparasitic). There are two genera: Pilostyles and Apodanthes . [2] A third genus, Berlinianche, was never validly published. [3]
The native range of Apodanthes is restricted to Central and tropical South America, [4] while Pilostyles has a much wider though disjointed native range, encompassing many countries in tropical and subtropical America, a section of Africa from Gabon to Tanzania and down to Zimbabwe, as well as Turkey, Iran, Iraq, and Western Australia. [5]
The relationship of the Apodanthaceae to other plant families remains unresolved, though recent research has given more clarity to the family's position and suggests inclusion in the order Malpighiales with a possible link to the family Rafflesiaceae. [6]
While the APG III system of classification (2009) listed the family's taxonomic position as uncertain [7] , the APG IV update in 2016 assigned it to the Cucurbitales [8] based on mitochondrial and nuclear DNA sequences. [9] However, two 2024 studies, both of which use large sets of nuclear DNA for analysis, indicate that it is a basal member of the Malpighiales. [10] [11]
The difficulty with using plastid DNA for phylogenetics of the Apodanthaceae was discussed in a 2021 study by Li et al. [12] This paper refers to the Apodanthaceae as one of five 'problematic' families (along with Balanophoraceae, Mitrastemonaceae, Rafflesiaceae, and Thismiaceae) and notes that plastome sequences in these families are highly reduced and they have unusually high substitution rates in the retained sequences, which can hamper proper phylogenetic alignment and cause long branch attraction artifacts.
The Cucurbitales are an order of flowering plants, included in the rosid group of dicotyledons. This order mostly belongs to tropical areas, with limited presence in subtropical and temperate regions. The order includes shrubs and trees, together with many herbs and climbers. One major characteristic of the Cucurbitales is the presence of unisexual flowers, mostly pentacyclic, with thick pointed petals. The pollination is usually performed by insects, but wind pollination is also present.
The Malpighiales comprise one of the largest orders of flowering plants. The order is very diverse, with well-known members including willows, violets, aspens and poplars, poinsettia, corpse flower, coca plant, cassava, flaxseed, castor bean, Saint John's wort, passionfruit, mangosteen, and manchineel tree.
Rosales are an order of flowering plants. Well-known members of Rosales include: roses, strawberries, blackberries and raspberries, apples and pears, plums, peaches and apricots, almonds, rowan and hawthorn, jujube, elms, banyans, figs, mulberries, breadfruit, nettles, hops, and cannabis.
Saxifragales is an order of angiosperms, or flowering plants, containing 15 botanical families and around 100 genera, with nearly 2,500 species. Of the 15 families, many are small, with eight of them being monotypic. The largest family is the Crassulaceae (stonecrops), a diverse group of mostly succulent plants, with about 35 genera. Saxifragales are found worldwide, primarily in temperate to subtropical zones, rarely being encountered growing wild in the tropics; however, many species are now cultivated throughout the world as knowledge of plant husbandry has improved. They can be found in a wide variety of environments, from deserts to fully aquatic habitats, with species adapted to alpine, forested or fully-aquatic habitats. Many are epiphytic or lithophytic, growing on exposed cliff faces, on trees or on rocks, and not requiring a highly organic or nutrient-dense substrate to thrive.
The Celastrales are an order of flowering plants found throughout the tropics and subtropics, with only a few species extending far into the temperate regions. The 1200 to 1350 species are in about 100 genera. All but seven of these genera are in the large family Celastraceae. Until recently, the composition of the order and its division into families varied greatly from one author to another.
Hamamelidaceae, commonly referred to as the witch-hazel family, is a family of flowering plants in the order Saxifragales. The clade consists of shrubs and small trees positioned within the woody clade of the core Saxifragales. An earlier system, the Cronquist system, recognized Hamamelidaceae in the Hamamelidales order.
The Angiosperm Phylogeny Group (APG) is an informal international group of systematic botanists who collaborate to establish a consensus on the taxonomy of flowering plants (angiosperms) that reflects new knowledge about plant relationships discovered through phylogenetic studies.
Phyllanthaceae is a family of flowering plants in the eudicot order Malpighiales. It is most closely related to the family Picrodendraceae.
Achariaceae is a family of flowering plants consisting of 31 genera and about 155 species of tropical herbs, shrubs, and trees. The APG IV system has greatly expanded the scope of the family by including many genera previously classified in Flacourtiaceae. Molecular data strongly support the inclusion of this family in the order Malpighiales.
Peridiscaceae is a family of flowering plants in the order Saxifragales. Four genera comprise this family: Medusandra, Soyauxia, Peridiscus, and Whittonia., with a total of 12 known species. It has a disjunct distribution, with Peridiscus occurring in Venezuela and northern Brazil, Whittonia in Guyana, Medusandra in Cameroon, and Soyauxia in tropical West Africa. Whittonia is possibly extinct, being known from only one specimen collected below Kaieteur Falls in Guyana. In 2006, archeologists attempted to rediscover it, however, it proved unsuccessful.
Hydnoroideae is a subfamily of parasitic flowering plants in the order Piperales. Traditionally, and as recently as the APG III system it given family rank under the name Hydnoraceae. It is now submerged in the Aristolochiaceae. It contains two genera, Hydnora and Prosopanche:
Dasypogonaceae is a family of flowering plants based on the type genus Dasypogon, one that has traditionally not been commonly recognized by taxonomists; the plants it contains were usually included in the family Xanthorrhoeaceae. If valid, Dasypogonaceae includes four genera with 16 species. The family is endemic to Australia. The best known representative is Kingia australis.
The Rafflesiaceae are a family of rare parasitic plants comprising 36 species in 3 genera found in the tropical forests of east and southeast Asia, including Rafflesia arnoldii, which has the largest flowers of all plants. The plants are endoparasites of vines in the genus Tetrastigma (Vitaceae) and lack stems, leaves, roots, and any photosynthetic tissue. They rely entirely on their host plants for both water and nutrients, and only then emerge as flowers from the roots or lower stems of the host plants.
The basal angiosperms are the flowering plants which diverged from the lineage leading to most flowering plants. In particular, the most basal angiosperms were called the ANITA grade, which is made up of Amborella, Nymphaeales and Austrobaileyales.
Lepidobotryaceae is a family of plants in the order Celastrales. It contains only two species: Lepidobotrys staudtii and Ruptiliocarpon caracolito.
Mesangiospermae is a clade that contains the majority of flowering plants (angiosperms). Mesangiosperms are therefore known as the core angiosperms, in contrast to the three orders of earlier-diverging species known as the basal angiosperms: Nymphaeales, Austrobaileyales, and Amborellales. Mesangiospermae includes about 350,000 species, while there are about 175 extant species of basal angiosperms.
When the APG II system of plant classification was published in April 2003, fifteen genera and three families were placed incertae sedis in the angiosperms, and were listed in a section of the appendix entitled "Taxa of uncertain position".
Hydrostachys is a genus of about 22 species of flowering plants native to Madagascar and southern and central Africa. It is the only genus in the family Hydrostachyaceae. All species of Hydrostachys are aquatic, growing on rocks in fast-moving water. They have tuberous roots, usually pinnately compound leaves, and highly reduced flowers on dense spikes.
Pilostyles is a genus of flowering plants in the family Apodanthaceae. It includes about 11 species of very small, completely parasitic plants that live inside the stems of woody legumes. Plants of this genus are sometimes referred to as stemsuckers.
Apodanthes is a genus of flowering plants in the family Apodanthaceae. It has only one currently accepted species, Apodanthes caseariae, native to Central America and northern South America. It is a holoparasite that lives inside plants from the families Salicaceae and Fabaceae, and emerges only to flower.