Babiana ringens

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Rat's tail
Babiana ringens1.jpg
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Monocots
Order: Asparagales
Family: Iridaceae
Subfamily: Ixioideae
Tribe: Ixieae
Genus: Babiana
Species: B. ringens
Binomial name
Babiana ringens
(L.) Ker Gawl.

The rat's tail (Babiana ringens) is a flowering plant endemic to Cape Province of South Africa.[1] The foliage is long and erect with an inflorescence consisting of a sterile main stalk adapted for ornithophily, pollination by birds. The plant bears bright red, tubular flowers on side branches close to the ground. It is a perennial that grows in nutrient-poor sandy soil[2] and flowers during the winter rains.[3]

Close view of the anthers with the stalk beside it.

The main stalk acts as a perch for birds, enabling birds to land within reach of the plant's flowers. The adaptation of the stalk was first noticed by Rudolf Marloth The bird that is the main pollinator of the plant is the malachite sunbird (Nectarina famosa).[4] The male sunbird is twice as likely to perch on the stalk as the female and, on average, spends four times longer on a perch. The stalk does seem to play a role in pollination as plants without a stalk produced only half as many seeds and see less cross-pollination as plants with a stalk intact. Accessing the flower from the stalk results in pollen being dusted on the breast of the sunbirds, although the birds may also sit on the ground to access flowers that lack stalks.[5] It has been suggested that the evolution of the bare axis and the flowers being borne at the base may have been driven by selection through the action of grazing herbivores.[6]

Subspecies[edit]

Two subspecies are recorded. The nominate ringens is found north of the Fish Hoek gap while australis is found further south with the northern-most record from Scarborough.

  1. Babiana ringens subsp. australis Goldblatt & J.C.Manning
  2. Babiana ringens subsp. ringens

References[edit]

  1. ^ "World Checklist of Selected Plant Families". Kew Science. 
  2. ^ Goldblatt P, Manning JC (2007). A revision of the southern African genus Babiana, Iridaceae: Crocoideae. South African National Biodiversity Institute. Pretoria: National Botanical Institute. pp. 1–98. ISBN 978-1-919976-32-7. 
  3. ^ de Waal C, Anderson B, Barrett SC (February 2012). "The natural history of pollination and mating in bird-pollinated Babiana (Iridaceae)". Annals of Botany. 109 (3): 667–79. doi:10.1093/aob/mcr172. PMC 3278289Freely accessible. PMID 21831856. 
  4. ^ Geerts S, Pauw A (2009). "Hyper-specialization for long-billed bird pollination in a guild of South African plants: the Malachite Sunbird pollination syndrome". South African Journal of Botany. 75 (4): 699–706. doi:10.1016/j.sajb.2009.08.001. 
  5. ^ Anderson B, Cole WW, Barrett SC (May 2005). "Botany: specialized bird perch aids cross-pollination". Nature. 435 (7038): 41–2. doi:10.1038/435041a. PMID 15875009. 
  6. ^ de Waal, C.; Barrett, S. C. H.; Anderson, B. (2012-05-21). "The effect of mammalian herbivory on inflorescence architecture in ornithophilous Babiana (Iridaceae): Implications for the evolution of a bird perch". American Journal of Botany. 99 (6): 1096–1103. doi:10.3732/ajb.1100295. ISSN 0002-9122. 

External links[edit]