In Haworthia Update Vol. 9 dealing with H. maculata, I again draw attention to several populations that are problematic in an area very difficult to explore. The populations are MBB7865 at Keurkloof southeast of DeDoorns, EA1441 at the Hex River Pass, an unrecorded population south of Sandhills (about 3km east of Kanetvlei) reported by Ernst van Jaarsveld. In addition there are two populations apparently of H. arachnoidea at Tunnel Station east of Osplaas.
The illustrations that accompany this article are:
- MBB6694 Vreesniet, Kanetvlei.
- EA1441 Hex River Pass, east DeDoorns.
- MBB7865 ex E. Van Jaarsveld, Keurkloof, DeDoorns.
This population MBB6694 is at Kanetvlei southeast of Sandhills, and I originally ascribed it to H. arachnoidea but this is not correct. To this I can add unexamined populations reported by P.V. Bruyns deep in the Langeberg at Keerom Dam and another of Ted Oliver in the mountains north of Nuy. MBB6694 is only 200-300m north of MBB7994 also in sandstone. The sandstone strata are by no means all the same and one can even find shale bands in what is essentially a sandstone formation. H. maculata flowers late winter to early spring and these other populations in early summer.
I have not examined the flowers in any number and remain doubtful that this information will clarify any deductions that can be drawn from the vegetative characters or the geographic positions of the populations. It appears to me that consideration must be given to a relationship with H. nortieri that in my assessment occurs from the far northwest to as far east as Prince Albert, i.e. H. nortieri (devriesii). What I have seen of the flower, and shown now is that it definitely does not belong in the context of the Southern Cape species where the bud-tips tend to be “fish-tailed”. The inflorescence are slender and few flowered.
There is some criticism of my emphasis on geographical distribution as a key indicator of species. It was even said, as though I would have denied the fact, that I could not identify plants unless I knew where they came from. There is an incredible amount of both ignorance and the obtuse behind these statements. One critic feels that I have ignored detail and even ignored flower characters in the development of my opinions. This same critic claims a high degree of agreement with me (80%) based apparently on the view that so much of my classification is correct (meets with his approval), and presumably that the 20 percent that he contributes to the system makes it 100% correct. This is wholly wrong. This critic is simply unable to bridge the historical chasm between his introduction to, or knowledge of, Haworthia and mine. He simply does not recognise the shift in method and why I switched from a “character-based” approach to a phytogeographic one. It is really very simple in that the character based system as used from the very beginning of classification, has not produced a solution to the identification and classification of Haworthia. It all rests on a very weak and shaky definition of species determined by breeding barriers and consequently that morphological differences necessarily exist. My approach was to show that breeding barriers (at least in plants) could be integral to species and that morphological differences could equally be nothing but variation within species. Therefore I arrived at a definition of species from the view that they were phenomena spread in space and changing with time. This is just a fundamental of plant species as they constitute the vegetation and the floras of the world. Virtually the first question following “What is that?”, is “where does it come from?”.
Why 6694 is so interesting is precisely because it occurs in an area which is so poorly known and represented in our knowledge of Haworthia. The reality in the subgenus Haworthia is that there are several areas of great species richness and there is real pattern in the distribution of the various elements as they are listed in the 80% agreement area. The 20% disagreement zone concerns truly trivial opinion and unsubstantiated statements, and almost ignores the real reasons for disagreement at all. The real reasons are the realities that superficial morphological difference does not mean species and I have posted a vast amount of material that demonstrates that. I have shown repeatedly that differences in single characters in what can be rationally said to be the same species, can be greater than between different species.
In the case of 6694 I did not pick any particular character to identify the plants as H. arachnoidea from probably as far back as 1975 and I can find no earlier record of this location. I do recall a specimen in the Compton herbarium made by W.F.Barker that I mentally allied with H. arachnoidea but it is not cited as such in my revision. The identification was based on little else other than the spiny-ness of the plants and the fact that the nearest known locality for that species was a very new one of mine a few kilometres to the southwest. At the time, H. nortieri was barely known and this was from far to the northwest at Clanwilliam. Since then H. nortieri has become much better known although still some distance north of Ceres, and with its globose-flowered variants at Laingsburg and eastwards. H. arachnoidea remains remarkably unknown from the Cedarberg and Koue Bokkeveld mountains but does appear in the upper Hex River Valley. Here it is odd that the leaves tend to have the translucent dots that one would expect to characterise H. nortieri. But otherwise the leaf coloration is the much darker green that is associated with H. arachnoidea. A twist is that at Kunje, southeast of Citrusdal, H. nortieri does have very dark green leaves and there is no doubt that confusion with H. arachnoidea is inevitable. I have very little to offer in this regard because this degree and level of confusion or doubt is intrinsic to the genus anyway.
Why I now decide to relate this Kanetvlei population to H. nortieri is not to be construed as a decision now to call white what previously was clearly and definitely black. It is taking all my knowledge and experience to suggest simply that this is a better reflection of the situation where there is not enough hard data to determine identity at a higher level of certainty than about 50%. What I do suggest that there are many situations in Haworthia as the case with H. maculata and H. pubescens only recently exposed. In this case the two very different elements can be very confidently be said to be the same in respect of distribution and linking populations AND characters. Throughout, particularly the subgenus Haworthia, we have situations of continuity and spatial (geographic trend) and nearly all my many publications deal with exactly this reality. What it suggests is that my critic should come to consider if he has some other motive between punting points of difference that prevent him from finding points of agreement, besides those that rest coldly on logic.
1. MBB6694 Vreesniet, Kanetvlei.
Flower profiles.
Flower faces.
Flower buds.
2. EA1441 Hex River Pass, east DeDoorns.
3. MBB7865 ex E. Van Jaarsveld, Keurkloof, DeDoorns.
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