Agavoideae is a subfamily of

monocot Monocotyledons (), commonly referred to as monocots, (Lilianae ''sensu'' Chase & Reveal) are flowering plants whose seeds contain only one Embryo#Plant embryos, embryonic leaf, or cotyledon. A monocot taxon has been in use for several decades, but ...

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Ancient Greek, Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed with ...

s in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Asparagaceae 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 ...

, order

Asparagales Asparagales (asparagoid lilies) are a diverse order of flowering plants in the monocots. Under the APG IV system of flowering plant classification, Asparagales are the largest order of monocots with 14 families, 1,122 genera, and about 36,00 ...

. It has previously been treated as a separate family, Agavaceae. The group includes many well-known

desert A desert is a landscape where little precipitation occurs and, consequently, living conditions create unique biomes and ecosystems. The lack of vegetation exposes the unprotected surface of the ground to denudation. About one-third of the la ...

and dry-zone types, such as the

agave ''Agave'' (; ; ) is a genus of monocots native to the arid regions of the Americas. The genus is primarily known for its succulent and xerophytic species that typically form large Rosette (botany), rosettes of strong, fleshy leaves. Many plan ...

s and yuccas (including the Joshua tree). About 640

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

are placed in around 23

genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...

; they are widespread in the tropical, subtropical, and warm temperate regions of the world.

Description and uses

Species may be

succulent In botany, succulent plants, also known as succulents, are plants with parts that are thickened, fleshy, and engorged, usually to retain water in arid climates or soil conditions. The word ''succulent'' comes from the Latin word ''sucus'', meani ...

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 Tequila (; ) is a liquor, distilled beverage made from the blue agave plant, primarily in the area surrounding the city of Tequila, Jalisco, Tequila northwest of Guadalajara, Jalisco, Guadalajara, and in the Jaliscan Highlands (''Los Altos (Jal ...

, pulque,'' and '' mezcal'', while others are valued for their fibers. They are quite popular for

xeriscaping Xeriscaping is the process of Garden design, landscaping, or gardening, that reduces or eliminates the need for irrigation. It is promoted in regions that do not have accessible, plentiful, or reliable supplies of fresh water and has gained acce ...

, as many have showy flowers.

Systematics

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, and Hesperocallidaceae, based on data from molecular systematics. Stevens comments that "The broad concept of Agavoideae ..may not seem very satisfactory" but that none of the alternatives is better. 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 ''Agave'' (; ; ) is a genus of monocots native to the arid regions of the Americas. The genus is primarily known for its succulent and xerophytic species that typically form large Rosette (botany), rosettes of strong, fleshy leaves. Many plan ...

'', is currently placed in the subfamily Nolinoideae.

Genera

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.

References

Sources

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External links