Encephalartos

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Encephalartos
Encephalartos lebomboensis - Lebombo cycad - desc-fruiting stalk.jpg
Encephalartos lebomboensis
Scientific classification
Kingdom: Plantae
Division: Cycadophyta
Class: Cycadopsida
Order: Cycadales
Family: Zamiaceae
Genus: Encephalartos
Lehm.
Encephalartos distribution.png
Geographical distribution of genus Encephalartos

Encephalartos is a genus of cycad native to Africa. Several species of Encephalartos are commonly referred to as bread palms, bread tree or Kaffir bread since a bread-like starchy food can be prepared from the centre of the stem. The genus name is derived from the Greek words en (within), kephali (head), and artos (bread), referring to the use of the pith to make food. They are, in evolutionary terms, some of the most primitive living gymnosperms.

All the species of Encephalartos are endangered. The whole genus is listed under CITES Appendix I / EU Annex A, and CITES prohibits international trade in specimens of these species except when the purpose of the import is not commercial, for instance for scientific research.

Description[edit]

Several of the species possess stout trunks. In E. cycadifolius, the main trunks are up to 10 feet (3.0 m) high, and several of them may be united at a base where a former main trunk once grew. The persistent, pinnate leaves are arranged in a terminal spreading crown, or ascending. The rigid leaflets are variously spiny or incised along their margins.

Cones[edit]

Male cones are elongated, and three or four may appear at a time. Female cones are borne singly, or up to three at a time, and may weigh up to 60 pounds (27 kg). In some species, male cones with ripe pollen emit a nauseating odour. When the pollen has been shed and the males cones decay, a strong odour of acetic acid has also been noted.[1]

Roots[edit]

Colonies of the cyanobacterium Nostoc punctiforme occur in apparent symbiosis inside the root tissue,[1] while the rootlets produce root tubercles at ground level which harbour a mycorrhizal fungus of uncertain function,[1] which is however suspected to facilitate the capturing of nitrogen from the air.[2]

Food value[edit]

In several species the pith of the trunk contains a copious amount of high quality starch below the crown. This was formerly cut out by native people as food. Thunberg recorded around 1772 that the Hottentots removed the stem's pith at the crown and buried it wrapped in animal skin[2] for about two months, after which they recovered it for kneading into bread,[1] whence the vernacular name "broodboom" (i.e. bread tree). The burial of the pith apparently facilitated its fermentation and softening,[1] and the dough was lightly roasted over a coal fire.[3] In 1779 Paterson likewise found that the pith of a "large palm" near King William's Town was utilised by the Africans and Hottentots as bread. The pith was removed and left till sourish, before it was kneaded into bread.[1][4]

Their large seeds consist of an often poisonous kernel covered by an edible fleshy layer.[2] Female cones are consequently destroyed by baboons, as they relish the pith around the seeds.[1] Monkeys, rodents and birds also feed on the seeds, but due to their unpredictable toxic qualities they are not recommended for human consumption.[2]

Conservation[edit]

In August 2014 thirteen Encephalartos latifrons cycads were stolen from Kirstenbosch Botanical Gardens in Cape Town, South Africa. The estimated value of all thirteen was at least R200,000 (US18,675). The plants were planted over 100 years ago as part of a research and reproduction program of this particular species of Encephalartos that no longer naturally reproduces in the wild. Encephalartos is highly valued as a garden or ornamental plant in many parts of the world and it is thought the plants were stolen to be sold on in the black market.[5]

Taxonomy[edit]

The genus was named by German botanist Johann Georg Christian Lehmann in 1834. All cycads except Cycas had been regarded as members of the genus Zamia until then, and some botanists continued to follow this line for many years after Lehmann had separated Encephalartos as a separate genus. His concept was originally much broader than the one accepted today, including also the Australian plants we now know as Macrozamia and Lepidozamia.[6]

Species[edit]

Reproductive cone of Encephalartos sclavoi.
  1. Encephalartos aemulans
  2. Encephalartos altensteinii
  3. Encephalartos aplanatus
  4. Encephalartos arenarius
  5. Encephalartos barteri
  6. Encephalartos brevifoliolatus
  7. Encephalartos bubalinus
  8. Encephalartos caffer
  9. Encephalartos calsloanii
  10. Encephalartos cerinus
  11. Encephalartos chimanimaniensis
  12. Encephalartos concinnus
  13. Encephalartos cupidus
  14. Encephalartos cycadifolius
  15. Encephalartos delucanus
  16. Encephalartos dolomiticus
  17. Encephalartos dyerianus
  18. Encephalartos equatorialis
  19. Encephalartos eugene-maraisii
  20. Encephalartos ferox
  21. Encephalartos friderici-guilielmi
  22. Encephalartos ghellinckii
  23. Encephalartos gratus
  24. Encephalartos heenanii
  25. Encephalartos hildebrandtii
  26. Encephalartos hirsutus
  27. Encephalartos horridus
  28. Encephalartos humilis
  29. Encephalartos inopinus
  30. Encephalartos ituriensis
  31. Encephalartos kisambo
  32. Encephalartos laevifolius
  33. Encephalartos lanatus
  34. Encephalartos latifrons
  35. Encephalartos laurentianus
  36. Encephalartos lebomboensis
  37. Encephalartos lehmannii
  38. Encephalartos longifolius
  39. Encephalartos mackenziei
  40. Encephalartos macrostrobilus
  41. Encephalartos manikensis
  42. Encephalartos marunguensis
  43. Encephalartos middelburgensis
  44. Encephalartos msinganus
  45. Encephalartos munchii
  46. Encephalartos natalensis
  47. Encephalartos ngoyanus
  48. Encephalartos nubimontanus
  49. Encephalartos paucidentatus
  50. Encephalartos poggei
  51. Encephalartos princeps
  52. Encephalartos pterogonus
  53. Encephalartos schaijesii
  54. Encephalartos schmitzii
  55. Encephalartos sclavoi
  56. Encephalartos senticosus
  57. Encephalartos septentrionalis
  58. Encephalartos tegulaneus
  59. Encephalartos transvenosus
  60. Encephalartos trispinosus
  61. Encephalartos turneri
  62. Encephalartos umbeluziensis
  63. Encephalartos villosus
  64. Encephalartos whitelockii
  65. Encephalartos woodii

See also[edit]

References[edit]

  1. ^ a b c d e f g Smith, Christo Albertyn (1966). Common Names of South African Plants. Botanical Survey Memoir 35. Pretoria: The Government Printer. pp. 179, 264. 
  2. ^ a b c d Palgrave, K.C. (1984). Trees of Southern Africa. Cape Town: Struik. p. 43. ISBN 0-86977-081-0. 
  3. ^ Van Bart, Martiens (16 May 1987). "Kirstenbosch kweek nou ook broodbome vir die publiek". Die Burger. Retrieved 21 January 2013. 
  4. ^ Paterson, William (1789), A Narrative of four Journeys into the Country of the Hottentots and Caffraria, in 1777-79 
  5. ^ Yeld, John (5 August 2014). "Endangered cycads stolen from Kirstenbosch". Cape Argus. Retrieved 21 August 2014. 
  6. ^ Alice Notten (May 2002). "Encephalartos woodii Sander". Kirstenbosch National Botanical Garden and South African National Biodiversity Institute. Retrieved 2006-11-16. 

External links[edit]