|Myrtus communis foliage and flowers|
|Family:|| Myrtaceae |
About 130; see list
Myrtaceae or the myrtle family is a family of dicotyledonous plants placed within the order Myrtales. Myrtle, pohutukawa, bay rum tree, clove, guava, acca (feijoa), allspice, and eucalyptus are some notable members of this group. All species are woody, contain essential oils, and have flower parts in multiples of four or five. The leaves are evergreen, alternate to mostly opposite, simple, and usually entire (i.e., without a toothed margin). The flowers have a base number of five petals, though in several genera the petals are minute or absent. The stamens are usually very conspicuous, brightly coloured and numerous.
Scientists hypothesize that the family Myrtaceae arose between sixty and fifty-six million years ago during the Paleocene era. Pollen fossils have been sourced to the ancient supercontinent Gondwana.The breakup of Gondwana during the Cretaceous period (145 to 66 Mya) geographically isolated disjunct taxa and allowed for rapid speciation: in particular, genera once considered members of the now-defunct Leptospermoideae alliance are now isolated within Oceania. Generally, experts agree that vicariance is responsible for the differentiation of Myrtaceae taxa, except in the cases of Leptospermum species now located on New Zealand and New Caledonia, islands which may have been submerged at the time of late Eocene differentiation.
Recent estimates suggest the Myrtaceae include approximately 5,950 species in about 132 genera.The family has a wide distribution in tropical and warm-temperate regions of the world, and is common in many of the world's biodiversity hotspots. Genera with capsular fruits such as Eucalyptus , Corymbia , Angophora , Leptospermum , and Melaleuca are absent from the Americas, apart from Metrosideros in Chile and Argentina. Genera with fleshy fruits have their greatest concentrations in eastern Australia and Malesia (the Australasian realm) and the Neotropics. Eucalyptus is a dominant, nearly ubiquitous genus in the more mesic parts of Australia and extends north sporadically to the Philippines. Eucalyptus regnans is the tallest flowering plant in the world. Other important Australian genera are Callistemon (bottlebrushes), Syzygium , and Melaleuca (paperbarks). Species of the genus Osbornia , native to Australasia, are mangroves. Eugenia , Myrcia , and Calyptranthes are among the larger genera in the neotropics.
Historically, the Myrtaceae were divided into two subfamilies. Subfamily Myrtoideae (about 75 genera) was recognized as having fleshy fruits and opposite, entire leaves. Most genera in this subfamily have one of three easily recognized types of embryos. The genera of Myrtoideae can be very difficult to distinguish in the absence of mature fruits. Myrtoideae are found worldwide in subtropical and tropical regions, with centers of diversity in the Neotropics, northeastern Australia, and Malesia. In contrast, subfamily Leptospermoideae (about 80 genera) was recognized as having dry, dehiscent fruits (capsules) and leaves arranged spirally or alternate. The Leptospermoideae are found mostly in Australasia, with a centre of diversity in Australia. Many genera in Western Australia have greatly reduced leaves and flowers typical of more xeric habitats.
The division of Myrtaceae into Leptospermoideae and Myrtoideae was challenged by a number of authors, including Johnson and Briggs (1984), who identified 14 tribes or clades within Myrtaceae, and found Myrtoideae to be polyphyletic.Molecular studies by several groups of authors, as of 2008, have confirmed the baccate (fleshy) fruits evolved twice from capsular fruits and, as such, the two-subfamily classification does not accurately portray the phylogenetic history of the family. Thus, many workers are now using a recent analysis by Wilson et al. (2001) as a starting point for further analyses of the family. This study pronounced both Leptospermoideae and Myrtoideae invalid, but retained several smaller suballiances shown to be monophyletic through matK analysis.
The genera Heteropyxis and Psiloxylon have been separated as separate families by many authors in the past as Heteropyxidaceae and Psiloxylaceae.However, Wilson et al. included them in Myrtaceae. These two genera are presently believed to be the earliest arising and surviving lineages of Myrtaceae.
The most recent classification recognizes 17 tribes and two subfamilies, Myrtoideae and Psiloxyloideae, based on a phylogenetic analysis of plastid DNA.
Many new species are being described annually from throughout the range of Myrtaceae. Likewise, new genera are being described nearly yearly.
Following Wilson (2011)
Myrtaceae is foraged by many stingless bees, especially by the species Melipona bicolor which gather pollen from this plant family.
Asparagales is an order of plants in modern classification systems such as the Angiosperm Phylogeny Group (APG) and the Angiosperm Phylogeny Web. The order takes its name from the type family Asparagaceae and is placed in the monocots amongst the lilioid monocots. The order has only recently been recognized in classification systems. It was first put forward by Huber in 1977 and later taken up in the Dahlgren system of 1985 and then the APG in 1998, 2003 and 2009. Before this, many of its families were assigned to the old order Liliales, a very large order containing almost all monocots with colorful tepals and lacking starch in their endosperm. DNA sequence analysis indicated that many of the taxa previously included in Liliales should actually be redistributed over three orders, Liliales, Asparagales, and Dioscoreales. The boundaries of the Asparagales and of its families have undergone a series of changes in recent years; future research may lead to further changes and ultimately greater stability. In the APG circumscription, Asparagales is the largest order of monocots with 14 families, 1,122 genera, and about 36,000 species.
The Ericaceae are a family of flowering plants, commonly known as the heath or heather family, found most commonly in acid and infertile growing conditions. The family is large, with c. 4250 known species spread across 124 genera, making it the 14th most species-rich family of flowering plants. The many well-known and economically important members of the Ericaceae include the cranberry, blueberry, huckleberry, rhododendron, and various common heaths and heathers.
The Myrtales are an order of flowering plants placed as a sister to the eurosids II clade as of the publishing of the Eucalyptus grandis genome in June 2014.
Rosaceae, the rose family, is a medium-sized family of flowering plants, including 4,828 known species in 91 genera.
The Rubiaceae are a family of flowering plants, commonly known as the coffee, madder, or bedstraw family. It consists of terrestrial trees, shrubs, lianas, or herbs that are recognizable by simple, opposite leaves with interpetiolar stipules. The family contains about 13,500 species in 611 genera, which makes it the fourth-largest angiosperm family. Rubiaceae has a cosmopolitan distribution; however, the largest species diversity is concentrated in the tropics and subtropics. Economically important species include Coffea, the source of coffee, Cinchona, the source of the antimalarial alkaloid quinine, some dye plants, and ornamental cultivars.
Eucalypt is a descriptive name for woody plants with capsule fruiting bodies belonging to seven closely related genera found across Australasia: Eucalyptus, Corymbia, Angophora, Stockwellia, Allosyncarpia, Eucalyptopsis and Arillastrum.
Taxaceae, commonly called the yew family, is a coniferous family which includes six extant and two extinct genera, and about 30 species of plants, or in older interpretations three genera and 7 to 12 species.
Malvaceae, or the mallows, is a family of flowering plants estimated to contain 244 genera with 4225 known species. Well-known members of economic importance include okra, cotton, cacao and durian. There are also some genera containing familiar ornamentals, such as Alcea (hollyhock), Malva (mallow) and Lavatera, as well as Tilia. The largest genera in terms of number of species include Hibiscus, Sterculia, Dombeya, Pavonia and Sida.
Ranunculaceae is a family of over 2,000 known species of flowering plants in 43 genera, distributed worldwide.
Lythraceae is a family of flowering plants, including 32 genera with about 620 species of herbs, shrubs and trees. The larger genera include Cuphea, Lagerstroemia (56), Nesaea (50), Rotala (45), and Lythrum (35). It also includes the pomegranate and the water caltrop. Lythraceae has a worldwide distribution, with most species in the tropics, but ranging into temperate climate regions as well.
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.
Marattiaceae is the only family of extant (living) ferns in the order Marattiales. In the Pteridophyte Phylogeny Group classification of 2016, Marattiales is the only order in the subclass Marattiidae. The family has six genera and about 110 species. Many are different in appearance from other ferns, having large fronds and fleshy rootstocks.
Brodiaeoideae are a monocot subfamily of flowering plants in the family Asparagaceae, order Asparagales. They have been treated as a separate family, Themidaceae. They are native to Central America and western North America, from British Columbia to Guatemala. The name of the subfamily is based on the type genus Brodiaea.
Scilloideae is a subfamily of bulbous plants within the family Asparagaceae. Scilloideae is sometimes treated as a separate family Hyacinthaceae, named after the genus Hyacinthus. Scilloideae or Hyacinthaceae include many familiar garden plants such as Hyacinthus (hyacinths), Hyacinthoides (bluebells), Muscari and Scilla and Puschkinia. Some are important as cut flowers.
Psiloxylon mauritianum is a species of flowering plant, the sole species of genus Psiloxylon. It is endemic to the Mascarene Islands in the Indian Ocean.
The Solanaceae, or nightshades, are a family of flowering plants that ranges from annual and perennial herbs to vines, lianas, epiphytes, shrubs, and trees, and includes a number of agricultural crops, medicinal plants, spices, weeds, and ornamentals. Many members of the family contain potent alkaloids, and some are highly toxic, but many—including tomatoes, potatoes, eggplant, bell and chili peppers—are used as food. The family belongs to the order Solanales, in the asterid group and class Magnoliopsida (dicotyledons). The Solanaceae consists of about 98 genera and some 2,700 species, with a great diversity of habitats, morphology and ecology.
Durioneae is a tribe within the subfamily Helicteroideae of the plant family Malvaceae s.l. The tribe contains at least five genera, including Durio, the genus of tree species that produce Durian fruits.
Eucalypteae is a large tribe of flowering plants in the family Myrtaceae; members of this tribe are known as eucalypts. In Australia the genera Angophora, Corymbia, and Eucalyptus are commonly known as gum trees, for the sticky substance that exudes from the trunk of some species. As of 2020, the tribe comprised around 860 species, all native to Southeast Asia and Oceania, with a main diversity center in Australia.
Polygonoideae is a subfamily of plants in the family Polygonaceae. It includes a number of plants that can be highly invasive, such as Japanese knotweed, Reynoutria japonica, and its hybrid with R. sachalinensis, R. × bohemica. Boundaries between the genera placed in the subfamily and their relationships have long been problematic, but a series of molecular phylogenetic studies have clarified some of them, resulting in the division of the subfamily into seven tribes.
Fergusonina, the sole genus in the family of Fergusoninidae, are gall-forming flies. There are about 40 species in the genus, all of them producing galls on Eucalyptus, Melaleuca, Corymbia, and Metrosideros species in Australia and New Zealand.
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