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.

The subfamily name is derived from the generic name of the type genus, Asphodelus. Members of this group can be found growing native in coastal Southern Africa, Central and Western Europe, the Mediterranean basin, Central Asia and Australia; one genus, Bulbinella, can additionally be found growing in New Zealand. The greatest diversity occurs in South Africa.

Several genera, notably Aloe, Asphodelus, Gasteria, Haworthia and Kniphofia are perhaps the best known of the family due to their use among plant collectors, botanists and horticulturists. Additional genera and hybrids are also known, including Aristaloe, Gasteraloe and Gonialoe (the latter formerly included the now-rehomed Aloe variegata, or partridge-breast aloe).

thumb|right|220px|Eremurus stenophyllus

Description

The Asphodeloideae are distinguished by a general presence of anthraquinones, simultaneous microsporogenesis, atypical ovules morphology, and the presence of an aril. Asphodeloideae also have a characteristic secondary growth by means of a secondary thickening meristem. The aloin cells are said to produce the characteristic thick exudate that is produced when the succulent leaf of aloe is severed. The monophyletic group can be treated as the tribe Aloeae within the subfamily Asphodeloideae by those adopting the broad APG IV system circumscription of the Asphodelaceae. (Alternatively, it may be treated as the subfamily Alooideae within a more narrowly circumscribed family Asphodelaceae.) The genera within Alooideae have several morphological characters that can be distinguished in the field, namely the arrangement and type of leaf and inflorescence.

Evidence for monophyly of Aloeae is based on distinctive karyotype and characteristic leaf morphology. The Bulbine group has characteristics of Aloeae, but is not included in the group due to a lack of tubular flowers. Kniphofia is considered an outgroup of Aloeae since it has tubular flowers and a fusion of perianth segments, but it lacks succulent leaves. Other treatments combine some of these genera into as few as seven.

  • Aloe <small>L.</small>
  • Aloiampelos <small>Klopper & Gideon F.Sm.</small>
  • Aloidendron <small>(A.Berger) Klopper & Gideon F.Sm.</small>
  • Aristaloe <small>Boatwr. & Manning</small>
  • Astroloba <small>Uitewaal</small>
  • Asphodeline <small>Rchb.</small>
  • Asphodelus <small>L.</small>
  • Bulbine <small>Wolf</small>
  • Bulbinella <small>Kunth</small>
  • Chortolirion <small>A.Berger</small>
  • Eremurus <small>M.Bieb.</small>
  • Gasteria <small>Duval</small>
  • Gonialoe <small>(Baker) Boatwr. & J.C.Manning</small>
  • Haworthia <small>Duval</small>
  • Haworthiopsis <small>G.D.Rowley</small>
  • Jodrellia <small>Baijnath</small>
  • Kniphofia <small>Moench</small>
  • Kumara <small>Medik</small>
  • Trachyandra <small>Kunth</small>
  • Tulista <small>Raf.</small>

For a phylogeny of the family, see the phylogenetic tree at Asphodelaceae.

References

Bibliography

  • Asphodeloideae At: Angiosperm Phylogeny Website At: Missouri Botanical Garden Website
  • Asphodelaceae in L. Watson and M.J. Dallwitz (1992 onwards). The families of flowering plants: descriptions, illustrations, identification, information retrieval. Version: 9 March 2006.
  • NCBI Taxonomy Browser
  • links at CSDL, Texas