Lobelia telekii
| Lobelia telekii | |
|---|---|
 | |
| Scientific classification | |
| Kingdom: | Plantae |
| (unranked): | Angiosperms |
| (unranked): | Eudicots |
| (unranked): | Asterids |
| Order: | Asterales |
| Family: | Campanulaceae |
| Subfamily: | Lobelioideae |
| Genus: | Lobelia |
| Species: | L. telekii Scwheinf |
| Binomial name | |
| Lobelia telekii | |
Lobelia telekii is a species of flowering plant in the bellflower family, Campanulaceae, that is found only in the alpine zones of Mount Kenya, Mount Elgon, and the Aberdare Mountains of East Africa. It lives at high altitudes on well-drained sloped hillsides. It is a semelparous species, putting all its reproductive effort into producing single large inflorescence up to 3 metres (10 ft), and then dying.[1]L. telekii also possesses a large pith-volume for internal water storage and marcescent foliage which could provide insulation and fire protection.[2] It secretes an ice-nucleating polysaccharide, which is useful for its survival in the cold climate. [3] The plant is named after the Austro-Hungarian explorer, Count Sámuel Teleki.
L. telekii plants usually consist of a single rosette, which grows for several decades, flowers once, and then dies. 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 lives 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. 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.
Taxonomy
Whereas L. telekii used to be classified under the Rhynchopetalum section within the Tupa subgenus [2] it has recently been reconfigured so that Tupa and Rhynchopetalum are their own separate sections, with L. telekii falling into the latter.[8] Now Tupa and Rhynchopetalum are clearly separated by their difference in chromosome count and geographic distribution, as well as a couple morphological variations.
References
- ↑ 1.0 1.1 Young, Truman P. (1990). "Evolution of semelparity in Mount Kenya lobelias". Evolutionary Ecology (Chapman and Hall Ltd) 4 (2): 157–171. doi:10.1007/BF02270913.
- ↑ 2.0 2.1 Knox, Eric B (1998). "Chloroplast DNA Evidence on the Origin and Radiation on the Giant Lobelias of Eastern Africa". Systematic Botany: 109–149.
- ↑ Krog, J.O. (1979). "Thermal buffering in afro-alpine plants due to nucleating agent-induced water freezing". Nature: 300–301.
- ↑ Young, Truman P. (1982). "Bird visitation, seed set, and germination rates in two species of Lobelia on Mount Kenya". Ecology 68: 1983–1986. doi:10.2307/1940139.
- ↑ 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.
- ↑ 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.
- ↑ 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.
- ↑ Lammers, Thomas (1998). "Revision of the Infrageneric Classification of Lobelia L. (Campanulaceae: Lobelioideae)". Annals of the Missouri Botanical Garden 4: 109–149.