Kotie Retief
In a unique spot near Lobowakgomo in the Limpopo province of South Africa, something special is happening. This area is, of course one of the hot spots when it comes to the number of species growing here. No less than seven aloe species occur in close proximity to this area.
At the fairly small spot under discussion, just south of the Olifants River, something truly amazing is happening - the hybridizing of two Aloe species at a pace hardly seen anywhere else (maybe nowhere else in the aloe world).
At least four aloe species grow in this area, A. marlothii, A. globuligemma, A. wickensii and A. mutans. It is a semi-arid region with very few trees and bigger plants, an ideal habitat for aloes. Succulents sharing the habitat include plants like Euphorbia cooperi, Euphorbia shinzii, a Senecio species and many others.
Where more than one species co-occur one often find hybrids. Aloes are pollinated mainly by birds, and they do not tend to stick with one species. What is absolutely amazing at this spot (an area probably not more than 3 km by 3 km) is the number of different hybrids between A. marlothii and A. globuligemma in a fairly undisturbed habitat. The unanswered question is: why did it happen here? We do not know about any similar spot. The late plant enthusiast, Charles Craib, who pointed out this spot to us, speculated that this a special type of speciation.
It has been said in the nomenclature discussions that hybridization between species (and genera) has not been taken seriously enough. If, for instance, a new species develop in the process mentioned above, what will the DNA evidence be able to say some time in the future?
To experience the variety of hybrids here is really something special. The photographs accompanying this article are an attempt to share some of the experience with the reader. It seems that there is no immediate threat to the habitat, but one will have to keep a close eye on future developments. One hopes that someone will be able to report in a hundred years’ time how the process panned out.
A typical hybrid of A. marlothii and A. globuligemma
A bicoloured hybrid
This hybrid is one of those where the plant does not look well, but the inflorescense is special
A. globuligemma upgraded with the colours of A. marlothii
A. wickensii sharing this special habitat with the other species, Euphorbia cooperi in the background.
A almost yellow plant close to A. marlothii, but with some hybrid genes. Photo: Sean Gildenhuys
The inflorescenses here are typically A. globuligemma, but the colours are that of A. marlothii. A bicoloured hybrid are to be seen on the left, in the background are hundreds of pure A. globuligemma plants.
Who would not like to have this hybrid in her/his garden?
It seems as if some of the hybrids are less resistant to insects, but the flowers are special.
Leaning towards A. globuligemma, but with A. marlothii genes present
Another very attractive hybrid. A double inflorescence is very common in the case of hybrids.
A hybrid which is really somewhere in between the two species
Seedlings grown from seed from the hybrid colony after five or six years growing in Pretoria. Prof. Gideon Smith has named the hybrids as Aloe xretiefii.