Helichrysum

The genus Helichrysum /hɛlɪˈkraɪsəm/ consists of an estimated 600 species of flowering plants in the sunflower family (Asteraceae). The type species is Helichrysum orientale. The name is derived from the Greek words ἑλίσσω (helisso, to turn around) and χρῡσός (chrysos, gold).

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

See text

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 (24–35 inches). The genus was a wastebasket taxon, and many of its members have been reclassified in smaller genera, most notably the Everlastings, now in the genus Xerochrysum.

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.

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).

Species

Hilliard (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 genus Helichrysum 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, Anaphalis, Achyrocline and Humeocline are probably congeneric with Helichrysum.[1]

Established species include

Helichrysum stoechas is similar to the Helichrysum arenarium, but the leaves are all linear, with rolled under edges. It is found in western France on dunes near the sea.

New species

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:

Uses
Helichrysum italicum essential oil in glass vial

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 italicum (synonym Helichrysum angustifolium) is steam distilled to produce a yellow-reddish essential oil popular in fragrance for its unique scent, best described as herbaceous, sweet, and honey-like. The epithet angustifolium means narrow leaved. It is commonly misspelled as augustifolium.[8]

Helichrysum candolleanum in Namibia

Notes
  1. Galbany-Casals, M. et al. 2014 Taxon, 63:608-624. Phylogenetic relationships in Helichrysum (Compositae: Gnaphalieae) and related genera: Incongruence between nuclear and plastid phylogenies, biogeographic and morphological patterns, and implications for generic delimitation
  2. Bussmann, R. W., et al. (2006). Plant use of the Maasai of Sekenani Valley, Maasai Mara, Kenya. J Ethnobiol Ethnomed 2 22.
  3. Miller, A. 2004. Helichrysum sp. nov. A. 2006 IUCN Red List of Threatened Species. Archived 2014-06-27 at the Wayback Machine Downloaded on 20 July 2007.
  4. Miller, A. 2004. Helichrysum sp. nov. B. 2006 IUCN Red List of Threatened Species. Archived 2014-06-27 at the Wayback Machine Downloaded on 20 July 2007.
  5. Miller, A. 2004. Helichrysum sp. nov. C. 2006 IUCN Red List of Threatened Species. Archived 2014-06-27 at the Wayback Machine Downloaded on 20 July 2007.
  6. Miller, A. 2004. Helichrysum sp. nov. D. 2006 IUCN Red List of Threatened Species. Archived 2014-06-27 at the Wayback Machine Downloaded on 20 July 2007.
  7. Miller, A. 2004. Helichrysum sp. nov. E. 2006 IUCN Red List of Threatened Species. Archived 2014-06-27 at the Wayback Machine Downloaded on 20 July 2007.
  8. http://www.floralimages.co.uk/info/botanicallatin.html for more details on botanical naming.

References
  • 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 Helipterum 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.
  • Xeranthemum annuum photo
  • Phylogenetic relationships within this genus
  • Helichrysum Essential Oil species
  • PHYLOGENY OF SOUTH AFRICAN GNAPHALIEAE (ASTERACEAE)
  • Details of botanical naming
  • Dressler, S.; Schmidt, M. & Zizka, G. (2014). "Helichrysum". African plants – a Photo Guide. Frankfurt/Main: Forschungsinstitut Senckenberg.
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