Lobelia deckenii

Lobelia deckenii
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Asterids
Order: Asterales
Family: Campanulaceae
Subfamily: Lobelioideae
Genus: Lobelia
Species: L. deckenii
Hemsl., 1877 [1]
Binomial name
Lobelia deckenii

Lobelia deckenii (syn. Lobelia keniensis) is a species of giant lobelia of the mountains of East Africa. It grows in moist areas, such as valley bottoms and moorland, in contrast to Lobelia telekii which grows in a similar, but drier habitat. These two species produce occasional hybrids. Lobelia deckenii plants often produce multiple rosettes, and plants with more rosettes flower more frequently. It is iteroparous.[2]

Lobelia deckenii plants usually consist of between one and eighteen rosettes, connected underground. Individual rosettes grow slowly in the alpine environment.[2] Individual rosettes may take decades to reach reproductive size, then die after flowering, but the connected rosettes live on.[2]

Lobelia deckenii is the only alpine species of lobelia that lives on Kilimanjaro[3].

Lobelia deckenii ssp. keniensis is the variety of Lobelia deckenii that lives on Mount Kenya, between 3,300m and 4,600m (10,800 - 15,100ft). It less eaten by rock hyrax than Lobelia telekii, which occurs more often in hyrax habitat. Lobelia species on Mount Kenya are all pollinated by birds[4][5], especially the Red-tufted Sunbird (also known as the Scarlet-tufted Malachite Sunbird) and the Alpine Chat.[6]

This species of giant lobelia is known for the reservoirs of water held in its rosettes, which freeze at night and protects the apical meristem held in a dense central leaf bud. When this reservoir is drained, the temperature of inner meristem drops below freezing, which does not occur when the fluid is left intact.[7] The crescent-shaped ice cubes formed in these rosettes give rise to the nickname, "Gin-and-tonic Lobelia".

References

  1. ^ International Plant Names Index
  2. ^ a b c Young, Truman P. (1984). "The comparative demography of semelparous Lobelia telekii and iteroparous Lobelia keniensis on Mount Kenya". Journal of Ecology 72 (2): 637–650. doi:10.2307/2260073. JSTOR 2260073. 
  3. ^ Guide to Mount Kenya and Kilimanjaro, Iain Allan (1991) Mountain Club of Kenya ISBN 978-9966985606
  4. ^ Young, Truman P. (1982). "Bird visitation, seed set, and germination rates in two species of Lobelia on Mount Kenya". Ecology 68: 1983–1986. 
  5. ^ Burd, Martin (1995). "Pollinator behavioural responses to reward size in Lobelia deckenii: no escape from pollen limitation of seed set". Journal of Ecology 83: 865–872. 
  6. ^ Smith, Alan P.; Truman P. Young (1987). "Tropical Alpine Plant Ecology". Annual Review of Ecology and Systematics 18: 137–158. doi:10.1146/annurev.es.18.110187.001033. 
  7. ^ Young, Truman P.; Susan Van Orden Robe (1986). "Micro-environmental role of a secreted aqueous solution in afro-alpine Lobelia keniensis". Biotropica 18 (3): 267–269. doi:10.2307/2388496. JSTOR 2388496.