Helichrysum

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Strawflower

Red Everlasting (Helichrysum sanguineum)
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Asterids
Order: Asterales
Family: Asteraceae
Subfamily: Asteroideae
Tribe: Gnaphalieae
Genus: Helichrysum
Mill., 1754
Species

Helichrysum arenarium - Dwarf Everlasting
Helichrysum foetidum - Stinking Strawflower
Helichrysum italicum - Curry Plant Helichrysum petiolare - Licorice Plant
Helichrysum sanguineum - Red Everlasting

The genus Helichrysum (pronounced hel-i-CRY-sum, or hee-li-CRY-sum) consists of an estimated 600 species, in the sunflower family (Asteraceae). The type species is Helichrysum orientale.

The name is derived from the Greek words helisso (to turn around) and chrysos (gold). Common names include strawflower and everlasting.

It occurs in Africa (with 244 species in South Africa), Madagascar, Australasia and Eurasia. The plants may be annuals, herbaceous perennials or shrubs, growing to a height of 60-90 cm.

Their leaves are oblong to lanceolate. They are flat and pubescent on both sides. The bristles of the pappus are scabrous, barbellate, or plumose.

The receptacle (base of the flower head) is often smooth, with a fringed margin, or honey-combed, and resemble daisies. They may be in almost all colors, except blue. There are many capitula and generally flat-topped corymbs or panicles. The corolla lobes show glandular hairs at the abaxial surface.

Several species are grown as ornamental plants, and for dried flowers. When cut young and dried, the open flowers and stalks preserve their colour and shape for long periods.

Helichrysum species are used as food plants by the larvae of some Lepidoptera species including the bucculaticid leaf-miners Bucculatrix gnaphaliella (which feeds exclusively on Helichrysum arenarium) and Bucculatrix helichrysella (feeds exclusively on H. italicum) and the Coleophora case-bearers C. caelebipennella, C. gnaphalii (feeds exclusively on H arenarium) and C. helichrysiella (feeds exclusively on H. italicum).

Helichrysum augustifolium is steam distilled to produce a yellow-reddish essential oil popular in fragrance for its unique scent, best described as a mixture of burnt sugar and ham.

[edit] Species

Hilllard (1983) divided this large and heterogeneous genus in 30 morphological groups. But this genus is controversial and is considered by many as an artificial genus. The taxonomy of the large polymorphic and probably polyphyletic Helichrysum genus is complex and not yet satisfactorily resolved. Several Australian species, such as H. acuminatum and H. bracteatum, have been reclassified in the genus Xerochrysum in 1991, resp. as X. subundulatum and X. bracteatum. In 1989, misaligned species of Helichrysum were reclassified in Syncarpha. Species included in Pseudognaphalium are probably congeneric with Helichrysum. In 2004, A. Miller identified five potentially new species that have not yet been published but were included in the IUCN Red List data, given their restricted range in Yemen. They are as follows:

  • Helichrysum sp. nov. A - Its natural habitat is rocky areas. It was given a status of "Vulnerable" by the IUCN.[1]
  • Helichrysum sp. nov. B - Its natural habitats are subtropical or tropical dry shrubland and rocky areas. It was given a status of "Vulnerable".[2]
  • Helichrysum sp. nov. C - Its natural habitat is rocky areas. It is threatened by habitat loss. It was given a status of "Endangered".[3]
  • Helichrysum sp. nov. D - Its natural habitat is rocky areas. It was given a status of "Endangered".[4]
  • Helichrysum sp. nov. E - Its natural habitat is rocky areas. It was given a status of "Data deficient".[5]

Established species include:

Helichrysum roseo-niveum in Namibia
Licorice Plant (Helichrysum petiolare)
Bracted Strawflower (Helichrysum bracteatum)
Helichrysum bracteatum with Flower-fly
Helichrysum moeserianum in Habitat, De Hoop N.R., South Africa
Helichrysum setosum (?)
Helichrysum umbraculigerum

[edit] References

  1. ^ Miller, A. 2004. Helichrysum sp. nov. A. 2006 IUCN Red List of Threatened Species. Downloaded on 20 July 2007.
  2. ^ Miller, A. 2004. Helichrysum sp. nov. B. 2006 IUCN Red List of Threatened Species. Downloaded on 20 July 2007.
  3. ^ Miller, A. 2004. Helichrysum sp. nov. C. 2006 IUCN Red List of Threatened Species. Downloaded on 20 July 2007.
  4. ^ Miller, A. 2004. Helichrysum sp. nov. D. 2006 IUCN Red List of Threatened Species. Downloaded on 20 July 2007.
  5. ^ Miller, A. 2004. Helichrysum sp. nov. E. 2006 IUCN Red List of Threatened Species. Downloaded on 20 July 2007.
  • HILLIARD, O. 1983. Flora of Southern Africa, Part 7 Inuleae, Fascicle 2 Gnaphaliinae. Government Printer, Pretoria, South Africa.
  • WILSON, P.G. 1992c. The classification of some Australian species currently included in elipterum and Helichrysum (Asteraceae: Gnaphalieae): part 3 Anemocarpa and Argentipallium, two new genera from Australia. Nuytsia 8: 447–460.
  • Mesfin Tadesse & Reilly, T. 1995. 17. A contribution to studies on Helichrysum (Compositae - Gnaphalieae) - a revision of the species of north-east tropical Africa. In: Advances in Compositae Systematics (eds. D.J.H. Hind, C. Jeffrey & G.V. Pope). Royal Botanic Gardens, Kew, pp. 379-450.

[edit] External links

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