Milligania | |
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Milligania densiflora | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Monocots |
Order: | Asparagales |
Family: | Asteliaceae |
Genus: | Milligania Hook. f. |
Species | |
See text. |
Milligania is a genus of native perennial plants containing five species which are all found in Tasmania: [1] [2] [3] [4] [5]
Formerly belonging to the Liliaceae family, Milligania is now a part of the Asteliaceae family. [4] Three of these species are alpine and subalpine, with the remaining two rare species growing along rivers in the south-west of the state. [4] All five species are restricted to very wet habitats and are typically found growing on waterlogged peat. [4] They are known to form extensive rough mats. [4]
Plants within this genus are perennial, rhizomatous, tufted herbs with short stems, often forming small clumps. [6] [7] [8] [9]
The broad, leathery leaves exhibit a triangular shape with pleats resembling those found in the Astelia genus. [4] [6] Leaves are alternately arranged [8] and sizes vary from quite small, measuring less than 5 cm in length, to large specimens reaching up to 1.25 m in length. [4] These leaves are sheathing in structure, with some silky hairs. [7]
The star-like flowers boast six tepals and are prominently displayed in inflorescences above the leaves. [4] [6] The flowers are pedicellate with basally fused tepals [9] which are primarily white, occasionally tinged with red at the tube mouth, with dense silky hairs that are rare in Aparagales. [7] [8] These inflorescences can reach heights of up to 50 cm, with flowers densely arranged in a panicle formation. [7] Each flower, measuring up to 1.5 cm wide, is abundant and spreading during the summer season. [7] Milligania species are all hermaphroditic and produce bisexual flowers. [11]
Milligania has a dry capsule fruit containing several seeds [9] which contrasts to the fleshy fruit commonly found in the genera Astelia and Neoastelia in the Asteliaceae family. [4] [5] [8] Milligania, and some Astelia species possess trilocular ovaries. [8] Skottsberg proposed that features such as the capsular fruit, bisexual flowers and simple hairs observed in Milligania are primitive traits, or plesiomorphic. [11] Milligania was considered to be divergent from other genera within the Asteliaceae family due to its semi-inferior ovary and dry fruit. [12]
While Asteliaceae taxa are distributed across Austral and Pacific regions, the primary centre of generic diversity is situated in Australia. [8] All five Milligania species are endemic to Tasmania. [8] According to a distribution map provided by the Atlas of Living Australia, Milligania is mainly distributed on the western side of the state, west of the geographical feature known as Tyler's Corridor. [14] This divide delineates significant differences in Tasmania's geology, climate, and vegetation. [14] Geological composition influences soil types, contributing to dramatic variations in vegetation across the state. [15] The western region typically experiences higher mean rainfall with acidic soils, leading to the prevalence of rainforest, moorland, and wet sclerophyll vegetation. [15] [16] Conversely, the eastern part of the state receives lower mean rainfall and has slightly more fertile soils, resulting in predominantly dry sclerophyll vegetation. [15] [16]
Plants within the Asteliaceae family exhibit a wide range of habitat preferences but generally thrive in environments with consistent moisture levels. [17] They are commonly found in tall, densely clustered habitats. [18] The five Milligania species occupy habitats ranging from lowland riparian valleys to alpine fellfields. [8]
The genus name 'Milligania' was initially documented in Hooker's J. Bot. Kew Gard. Misc. 5: 296 (1853). [19] However, its placement within the Asteliaceae family has faced challenges due to insufficient support in a cladistic analysis involving both morphological and molecular data. [12] It has been regarded as an outlier within the family, diverging from the typical characteristics observed in other genera. [20] A cladistic study conducted by Maciunas et al. in 2011 revealed a potential sister relationship between the Neoastelia/Milligania and Collospermum/Astelia clades, based on analysis of morphological data. [21]
Asparagales |
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Within the Asteliaceae family, studies conducted in 2012 and 2013 grouped Milligania with Astelia. [8] [22] A 2021 study placed Neoastelia and Milligania as sisters: [23]
Asteliaceae |
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Milligania johnstonii and Milligania longifolia are listed as rare under the Threatened Species Act 1995. [24] [25] Milligania densiflora is not considered to be at risk in the wild. [26] There is no known status for Milligania lindoniana or Milligania stylosa.
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 Dioscoreales are an order of monocotyledonous flowering plants, organized under modern classification systems, such as the Angiosperm Phylogeny Group or the Angiosperm Phylogeny Web. Among monocot plants, Dioscoreales are grouped with the lilioid monocots, wherein they are a sister group to the Pandanales. In total, the order Dioscoreales comprises three families, 22 genera and about 850 species.
Monocotyledons, commonly referred to as monocots, are grass and grass-like flowering plants (angiosperms), the seeds of which typically contain only one embryonic leaf, or cotyledon. They constitute one of the major groups into which the flowering plants have traditionally been divided; the rest of the flowering plants have two cotyledons and are classified as dicotyledons, or dicots.
Iridaceae is a family of plants in order Asparagales, taking its name from the irises. It has a nearly global distribution, with 69 accepted genera with a total of c. 2500 species. It includes a number of economically important cultivated plants, such as species of Freesia, Gladiolus, and Crocus, as well as the crop saffron.
Asphodelaceae is a family of flowering plants in the order Asparagales. Such a family has been recognized by most taxonomists, but the circumscription has varied widely. In its current circumscription in the APG IV system, it includes about 40 genera and 900 known species. The type genus is Asphodelus.
Asteliaceae is a family of flowering plants, placed in the order Asparagales of the monocots.
Boryaceae is a family of highly drought-tolerant flowering plants native to Australia, placed in the order Asparagales of the monocots. The family includes two genera, with twelve species in total in Australia.
Astelia is a genus of flowering plants in the recently named family Asteliaceae. They are rhizomatous tufted perennials native to various islands in the Pacific, Indian, and South Atlantic Oceans, as well as to Australia and to the southernmost tip of South America. A significant number of the known species are endemic to New Zealand. The species generally grow in forests, swamps and amongst low alpine vegetation; occasionally they are epiphytic.
Lilioid monocots is an informal name used for a grade of five monocot orders in which the majority of species have flowers with relatively large, coloured tepals. This characteristic is similar to that found in lilies ("lily-like"). Petaloid monocots refers to the flowers having tepals which all resemble petals (petaloid). The taxonomic terms Lilianae or Liliiflorae have also been applied to this assemblage at various times. From the early nineteenth century many of the species in this group of plants were put into a very broadly defined family, Liliaceae sensu lato or s.l.. These classification systems are still found in many books and other sources. Within the monocots the Liliaceae s.l. were distinguished from the Glumaceae.
Alan W. Meerow is an American botanist, born in New York City in 1952. He specializes in the taxonomy of the family Amaryllidaceae and the horticulture of palms and tropical ornamental plants. He also works on the population genetics and molecular systematics of cycads and palms.
Amaryllidoideae is a subfamily of monocot flowering plants in the family Amaryllidaceae, order Asparagales. The most recent APG classification, APG III, takes a broad view of the Amaryllidaceae, which then has three subfamilies, one of which is Amaryllidoideae, and the others are Allioideae and Agapanthoideae. The subfamily consists of about seventy genera, with over eight hundred species, and a worldwide distribution.
The taxonomy of the plant family Liliaceae has had a complex history since its first description in the mid-eighteenth century. Originally, the Liliaceae were defined as having a "calix" (perianth) of six equal-coloured parts, six stamens, a single style, and a superior, three-chambered (trilocular) ovary turning into a capsule fruit at maturity. The taxonomic circumscription of the family Liliaceae progressively expanded until it became the largest plant family and also extremely diverse, being somewhat arbitrarily defined as all species of plants with six tepals and a superior ovary. It eventually came to encompass about 300 genera and 4,500 species, and was thus a "catch-all" and hence paraphyletic. Only since the more modern taxonomic systems developed by the Angiosperm Phylogeny Group (APG) and based on phylogenetic principles, has it been possible to identify the many separate taxonomic groupings within the original family and redistribute them, leaving a relatively small core as the modern family Liliaceae, with fifteen genera and 600 species.
Cyanastrum is a genus of plants in the family Tecophilaeaceae, native to tropical Africa. It contains three currently recognized species.
Eustephieae is a flowering plant tribe in the family Amaryllidaceae, subfamily Amaryllidoideae. It forms part of the Andean clade, one of two clades in The Americas.
Stenomesseae was a tribe, where it forms part of the Andean clade, one of two American clades. The tribe was originally described by Traub in his monograph on the Amaryllidaceae in 1963, as Stenomessae based on the type genus Stenomesson. In 1995 it was recognised that Eustephieae was a distinct group separate from the other Stenomesseae. Subsequently, the Müller-Doblies' (1996) divided tribe Eustephieae into two subtribes, Stenomessinae and Eustephiinae.
Eucharideae is a tribe of plants within the family Amaryllidaceae. It was augmented in 2000 by Meerow et al. following a molecular phylogenetic study that revealed that many elements of the tribe Stenomesseae segregated with it, rather than separately, and were subsequently submerged in it. Further revisions were made in 2020, when three genera were merged. It forms one of the tribes of the Andean subclade of the American clade of the subfamily.
Clinantheae is a tribe, where it forms part of the Andean clade, one of two American clades. The tribe was described in 2000 by Alan Meerow et al. as a result of a molecular phylogenetic study of the American Amaryllidoideae. This demonstrated that the tribe Stenomesseae, including the type genus Stenomesson was polyphyletic. Part of the tribe segregated with the Eucharideae and were submerged into it, while the other part formed a unique subclade. Since the type species of Stenomesson was not part of the second subclade, it was necessary to form a new name for the remaining species together with the other genera that remained. This was Clinanthus, the oldest name for these species, and consequently the tribe Clinantheae.
Hymenocallideae is a tribe, where it forms part of the Andean clade, one of two American clades. The tribe was originally recognised by both Meerow (1995) and the Muller-Doblies' (1996). Its phylogenetic position within the Amaryllidoideae was established by Meerow et al. in 2000, while in-depth infratribal relationships were established in 2002.
Astelia alpina called pineapple grass, silver astelia, or perching lily is a commonly found species in alpine and subalpine areas of Tasmania and the Australian Alps. It is a perennial herb that typically dominates its environment by growing in dense clusters, called mats, in alpine bogs. There are two subspecies: Astelia alpina var. novae hollandiae from New South Wales and Victoria and Astelia alpina var. alpina endemic to Tasmania. Both subspecies appear very similar to each other. The species was originally described by Robert Brown.
Diplaspis cordifolia is an endemic Tasmanian herb, known commonly as western mountain-pennywort. It is found in alpine vegetation communities across Tasmania, most commonly in the West and South-western areas.