Agavoideae | |
---|---|
Agave victoriae-reginae | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Monocots |
Order: | Asparagales |
Family: | Asparagaceae |
Subfamily: | Agavoideae Herb |
Type genus | |
Agave | |
Genera | |
See text |
Agavoideae is a subfamily of monocot flowering plants in the family Asparagaceae, order Asparagales. It has previously been treated as a separate family, Agavaceae. [1] The group includes many well-known desert and dry-zone types, such as the agaves and yuccas (including the Joshua tree). About 640 species are placed in around 23 genera; [2] they are widespread in the tropical, subtropical, and warm temperate regions of the world.
Species may be succulent or not. In general, Agavoideae leaves occur as rosettes at the end of a woody stem, which may range from extremely short to tree-like heights, as in the Joshua tree. The leaves are parallel-veined, and usually appear long and pointed, often with a hardened spine on the end, and sometimes with additional spines along the margins.
Agave species are used to make tequila, pulque, and mezcal , while others are valued for their fibers. They are quite popular for xeriscaping, as many have showy flowers.
The taxonomy of the group has varied widely. In the APG III system of 2009, adopted here, the Agavoideae are defined very broadly to include the former family Agavaceae along with other formerly separate families such as Anemarrhenaceae, Chlorogalaceae, Hostaceae, Yuccaceae, Anthericaceae, Hesperocallidaceae, and Chlorogalaceae, based on data from molecular systematics. [3] Stevens comments that "The broad concept of Agavoideae [...] may not seem very satisfactory" but that none of the alternatives is better. [2] Sources prior to 2009 will still have Agavaceae (in varying circumscriptions) as a separate family and may contain varying numbers of other families included in the Agavoideae in the APG III system.
Some genera formerly placed in this group (under whatever name) have been separated off; e.g. Dracaena , which superficially resembles some species of Agave , is currently placed in the subfamily Nolinoideae. [1]
A partial list of the genera included in the Agavoideae is given below. The reference is to the source that places the genus in this subfamily. As noted above, the genera currently included here have varied widely in their limits and assignment to families and subfamilies; some former family placements other than Agavaceae are found in the literature are given below. [2] [4]
Genus | Former family placement(s) outside Agavaceae/Agavoideae |
Agave L. [1] | |
Anemarrhena Bunge [1] | Anemarrhenaceae |
Anthericum L. [1] | Anthericaceae |
Behnia Didr. [1] | Behniaceae, Philesiaceae |
Beschorneria Kunth [1] | |
Camassia Lindl. [1] | Chlorogalaceae, Hyacinthaceae |
Chlorogalum (Lindl.) Kunth [1] | Chlorogalaceae, Hyacinthaceae |
Chlorophytum Ker Gawl. [1] | Anthericaceae |
Clara Kunth | Herreriaceae |
Diamena Ravenna [5] | |
Diora Ravenna [5] | Anthericaceae |
Diuranthera Hemsl. | |
Echeandia Ortega [1] | Anthericaceae |
Eremocrinum M.E.Jones [2] | |
Furcraea Vent. [2] | |
Hagenbachia Nees & Mart. [5] | |
Hastingsia S.Watson [1] | Chlorogalaceae, Hyacinthaceae |
Herreria Ruiz & Pav. [1] | Herreriaceae |
Herreriopsis H.Perrier [1] | Herreriaceae |
Hesperaloe Engelm. in S.Watson [5] | |
Hesperocallis A.Gray [1] | Hesperocallidaceae, Hyacinthaceae |
Hesperoyucca (Engelm.) Trel. [5] (included in Yucca by some sources) | Yuccaceae |
Hosta Tratt. [1] | Hostaceae |
Leucocrinum Nutt. ex A.Gray [1] | Anthericaceae |
Manfreda Salisb. [2] (included in Agave by some sources) | |
Paradisea Mazzuc. [1] | Asphodelaceae |
Polianthes L. [2] (included in Agave by some sources) | |
Prochnyanthes S.Watson [5] | |
Schoenolirion Durand [1] | Chlorogalaceae, Hyacinthaceae |
Trihesperus Herb. | |
Yucca L. [1] (including Samuela) | Yuccaceae |
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 Alismatales (alismatids) are an order of flowering plants including about 4,500 species. Plants assigned to this order are mostly tropical or aquatic. Some grow in fresh water, some in marine habitats. Perhaps the most important food crop in the order is the corm of the taro plant, Colocasia esculenta.
Petrosaviaceae is a family of flowering plants belonging to a monotypic order, Petrosaviales. Petrosaviales are monocots, and are grouped within the lilioid monocots. Petrosaviales is a very small order – one family, two genera and four species were accepted in 2016 – ) of photosynthetic (Japonolirion) and rare, leafless, achlorophyllous, mycoheterotrophic plants (Petrosavia), found in low-light montane rainforests in Japan, China, Southeast Asia and Borneo. They are characterised by having bracteate racemes, pedicellate flowers, six persistent tepals, septal nectaries, three almost-distinct carpels, simultaneous microsporogenesis, monosulcate pollen, and follicular fruit.
Asphodeloideae is a subfamily of the monocot family Asphodelaceae in the order Asparagales. It has previously been treated as a separate family, Asphodelaceae sensu stricto. The family Asphodelaceae has now been proposed to be a nomen conservandum, and the proposal has been recommended for ratification in 2017. In that case, Asphodelaceae will have priority over Xanthorrhoeaceae. This is reflected in the APG IV family lists.
Hemerocallidoideae is the a subfamily of flowering plants, part of the family Asphodelaceae sensu lato in the monocot order Asparagales according to the APG system of 2016. Earlier classification systems treated the group as a separate family, the Hemerocallidaceae. The name is derived from the generic name of the type genus, Hemerocallis. The largest genera in the group are Dianella, Hemerocallis (15), and Caesia (11).
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.
Nolinoideae is a monocot subfamily of the family Asparagaceae in the APG III system of 2009. It used to be treated as a separate family, Ruscaceae s.l. The family name is derived from the generic name of the type genus, Nolina.
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.
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.
Asparagaceae, known as the asparagus family, is a family of flowering plants, placed in the order Asparagales of the monocots. The family name is based on the edible garden asparagus, Asparagus officinalis. This family includes both common garden plants as well as common houseplants. The garden plants include asparagus, yucca, bluebell, and hosta, and the houseplants include snake plant, corn cane, spider plant, and plumosus fern.
Lomandroideae is a subfamily of monocot flowering plants in the family Asparagaceae, order Asparagales, according to the APG III system of 2009. The subfamily name is derived from the generic name of the type genus, Lomandra. The group has previously been treated as a separate family Laxmanniaceae. In the Kubitzki system, it is treated as Lomandraceae Lotsy.
Hesperocallis is a genus of flowering plants that includes a single species, Hesperocallis undulata, known as the desert lily or ajo lily.
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.
Tecophilaeaceae is a family of flowering plants, placed in the order Asparagales of the monocots. It consists of nine genera with a total of 27 species.
Doryanthes is the sole genus in the flowering plant family Doryanthaceae. The genus consists of two species, D. excelsa and D. palmeri, both endemic natives of the coast of Eastern Australia. Doryanthaceae is part of the order Asparagales.
The Anarthriaceae are a family of three genera, Anarthria, Hopkinsia and Lyginia of flowering plants, now included in Restionaceae following APG IV (2016). The family is accepted in the Angiosperm Phylogeny Group's classification system, APG III system, but is not considered a separate family in many other taxonomic systems. The three genera are herbaceous but differ greatly in characteristics.
Centrolepidaceae are a family of flowering plants now included in Restionaceae following APG IV (2016). The botanical name has been recognized by most taxonomists.
Agave is a genus of monocots native to the hot and arid regions of the Americas and the Caribbean, although some Agave species are also native to tropical areas of North America, such as Mexico. The genus is primarily known for its succulent and xerophytic species that typically form large rosettes of strong, fleshy leaves. Agave now includes species formerly placed in a number of other genera, such as Manfreda, ×Mangave, Polianthes and Prochnyanthes.
Herreriopsis is a genus of one species of flowering plants, endemic to Madagascar. In the APG III classification system, the genus is placed in the family Asparagaceae, subfamily Agavoideae. The sole species is Herreriopsis elegans.
The Asparagales are an order of plants, and on this page the structure of the order is used according to the APG III system. The order takes its name from the family Asparagaceae and is placed in the monocots. The order is clearly circumscribed on the basis of DNA sequence analysis, but is difficult to define morphologically, since its members are structurally diverse. The APG III system is used in World Checklist of Selected Plant Families from the Royal Botanical Gardens at Kew. With this circumscription, the order consists of 14 families with approximately 1120 genera and 26000 species.