Lobelia telekii

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Lobelia telekii
Lobelia telekii2.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Asterids
Order: Asterales
Family: Campanulaceae
Genus: Lobelia
Species:
L. telekii
Binomial name
Lobelia telekii
Scwheinf.

Lobelia telekii is a species of flowering plant in the family Campanulaceae, that is found only in the alpine zones of Mount Kenya, Mount Elgon, and the Aberdare Mountains of East Africa. It occurs at higher altitudes on well-drained sloped hillsides. It is a semelparous species, growing vegetatively for about 40 years and putting putting all its reproductive effort into producing single large inflorescence up to 3 metres (10 ft) tall before dying. [1] Inflorescences of L. telekii also possesses a large pith-volume for internal water storage and marcescent foliage which could provide insulation. [2] It secretes a polysaccharide into this reservoir, which may be useful for its survival in the cold climate. [3] The plant is named after the Austro-Hungarian explorer, Count Sámuel Teleki.

Contents

The inflorescence of Lobelia telekii can grow up to 3 metres (10 ft) tall Lobelia telekii without mehmet.jpg
The inflorescence of Lobelia telekii can grow up to 3 metres (10 ft) tall

L. telekii plants usually consist of a single rosette, which grows for several decades, flowers once, and then dies (a strategy termed as semelparity). However, a very small number of plants have multiple rosettes connected by an underground stem. [1] Each flower is subtended by a long hairy bract, and the overall appearance has led to the nickname "Cousin Itt lobelia".

The bird-pollinated flowers [4] [5] of L. telekii are hidden among the large bracts within the inflorescence. The leaves and bracts are blue-green, and the flowers purple. [6] Each flower can produce up to several hundred small (<1mm diameter) dark seeds, which are passively dispersed.

On Mount Kenya, Lobelia telekii occurs at elevations of 3,500–5,000 metres (11,500–16,400 ft). It inhabits the drier hill slopes, while its close relative Lobelia keniensis prefers the moister valley bottoms. Partially fertile hybrids do occur. The hill slopes often have rocky moraines that are home to Mount Kenya rock hyrax, which sometimes eat lobelia leaves and inflorescences, [7] but herbivores are generally deterred by the lobelia's bitter toxic sap, which contains alkaloids, probably including lobeline.

Ecology

Lobelia telekii is pollinated mainly by birds, especially the scarlet-tufted malachite sunbird (Nectarinia johnstoni) which visits the inflorescence for nectar. It often visits the male flowers at the apex which are produced first (protandrous) and have more sugar than the female flowers that appear later at the base of the inflorescence. The birds defend their favourite stands of plants from other individuals of their species. [8] The plants are eaten by rock hyrax ( Procavia capensis johnstoni ) in the dry season. The plant is protected by a latex and few other animals eat the plant. [9] [10] The rosettes of leaves hold water in the centre into which polysaccharides are exuded by the plant which are thought to cause ice-nucleation, preventing the plant tissue itself from freezing. They also hold fluid inside the inflorescences. [11] This material has inspired the design of protection mechanisms for solar panels and other structures from ice. [12]

Taxonomy

Lobelia telekii was previously classified under the Rhynchopetalum section within the Tupa subgenus. [2] The genus has since been reconfigured so that Tupa and Rhynchopetalum are separate sections, with L. telekii falling into the latter. [13] Tupa and Rhynchopetalum are separated by their difference in chromosome count and geographic distribution, supported by morphological differences.

References

  1. 1 2 Young, Truman P. (1990). "Evolution of semelparity in Mount Kenya lobelias". Evolutionary Ecology. 4 (2). Chapman and Hall Ltd: 157–171. doi:10.1007/BF02270913. S2CID   25993809.
  2. 1 2 Knox, Eric B (1998). "Chloroplast DNA Evidence on the Origin and Radiation on the Giant Lobelias of Eastern Africa". Systematic Botany. 23 (2): 109–149. doi:10.2307/2419583. JSTOR   2419583.
  3. Krog, J.O. (1979). "Thermal buffering in afro-alpine plants due to nucleating agent-induced water freezing". Nature. 282 (5736): 300–301. Bibcode:1979Natur.282..300K. doi:10.1038/282300a0. S2CID   4368345.
  4. Young, Truman P. (1982). "Bird visitation, seed set, and germination rates in two species of Lobelia on Mount Kenya". Ecology. 68 (6): 1983–1986. doi:10.2307/1940139. JSTOR   1940139.
  5. Smith, Alan P.; Truman P. Young (1987). "Tropical Alpine Plant Ecology". Annual Review of Ecology and Systematics. 18 (1): 137–158. doi:10.1146/annurev.es.18.110187.001033.
  6. Mabberley, D. J. (1975). "The Giant Lobelias: Pachycauly, biogeography, ornithophily and continental drift". New Phytologist. 74 (2): 365–374. doi: 10.1111/j.1469-8137.1975.tb02623.x .
  7. 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.
  8. Evans, Matthew R. (1996). "Nectar and flower production of Lobelia telekii inflorescences, and their influence on territorial behaviour of the scarlet-tufted malachite sunbird (Nectarinia johnstoni)". Biological Journal of the Linnean Society. 57 (2): 89–105. doi:10.1111/j.1095-8312.1996.tb01831.x.
  9. Young, Truman P. (1984). "The Comparative Demography of Semelparous Lobelia Telekii and Iteroparous Lobelia Keniensis on Mount Kenya" (PDF). Journal of Ecology. 72 (2): 637–650.
  10. Young, Truman P. (1985). "Lobelia telekii Herbivory, Mortality, and Size at Reproduction: Variation with Growth Rate" (PDF). Ecology. 66 (6): 1879–1883.
  11. Embuscado, Milda E.; BeMiller, James N.; Knox, Eric B. (1996). "A survey and partial characterization of iceucleating fluids secreted by giant-rosette (Lobelia and Dendrosenecio) plants of the mountains of eastern Africa". Carbohydrate Polymers. 31 (1–2): 1–9. doi:10.1016/S0144-8617(96)00120-8.
  12. Zhang, Yidan; Guo, Zhiguang (2025). "Lobelia-Inspired Photothermal Storage Flexible Film for Efficient Deicing". Small Methods. 9 (7): 2402006. doi:10.1002/smtd.202402006. ISSN   2366-9608.
  13. Lammers, Thomas (2011). "Revision of the Infrageneric Classification of Lobelia L. (Campanulaceae: Lobelioideae)". Annals of the Missouri Botanical Garden. 98: 37–62. doi:10.3417/2007150. S2CID   84676862.