• Van Reenens Crest
• Aloe pumila, Haworthia pumila; what or who is confused?
• Haworthia limifolia – a conundrum or a lesson?
• Haworthia marxii and H. truteriorum in relation to rational classification.
• Very brief note re Haworthia nortieri flowers.
• The reality of Drosanthemum micans L.
• New finds in Haworthia.
• What do collectors need?
• Righting some misconceptions.
• Comments on H. marxii
• Haworthia maculata ↔ Haworthia pubescens, MBB8002 Cilmor.
• Addendum Haworthia pubescens MBB8011, SW Sandberg
• Genetic history – the place in Haworthia classification.
• Haworthia mutica (groenewaldii) and its twisted leaves.
• Comprehension and significance
• Habitats
• MBB6694 Kanetvlei, Hex River Valley as a variant of Haworthia nortieri.
• Haworthia minima and pumila flowers
• MBB7989 Haworthia pumila, Lemoenpoort
• Leaf arrangement in Aloe striatula
• Just what do we do with names for Haworthia?
• The absurdity of taxonomy and nomenclature?
• Variable chloracantha
• Leaf sequence in Haworthia emelyae ‘comptoniana’ over a long period
• What do you think this is?
• Kaboega
• Habitat Views
• Haworthia Species Mystery Supplement
• Dunning-Kruger Effect
• Flowering Time

Explanatory note: In a rationalized list of names I wrote and had published in Haworthia Update Vol 7. I made two decisions. On of these was in respect of H. marxii and the other in respect of H. truteriorum. In the case of H. marxi I included it under H. emelyae. In the case of H. truteriorum, I placed this under H. bayeri. In neither case did I have good evidence for doing so, much other than my conviction that a classification is intended to reflect origins and relationships. In formalizing names one perforce is pressured into making decisions that you are not informed enough to make. My main defense is that the authors of the two species were not adequately informed either. I think their account of H. mutica (their H. groenewaldii) at Buffeljags demonstrates this. H. marxii presents particular problems that I simply do not have any substantial data that I can process.  In the case of H. truteriorum I did have some to which I can now add. This suggests as Breuer and Marx indirectly indicate, that H. truteriorum relates to my concept of H. mirabilis.   I concede that I may be quite wrong in attributing it to H. bayeri. I find it very difficult to see the decision to describe it as a distinct species as a logical scientific action. This article does not extol any imagined virtues or skills of mine. It is only intended to further project my opinion that we urgently need to work towards a classification that does satisfy scientific principle and not novelty or commercial ends. It is also a counter to some very negative opinion aimed in my direction.

At a level above classification lies respect for people and their feelings.  Therefore this writing should not be seen as anything but a commentary on the classification process and not how this can also denigrate people as much as honor them. H. marxii is described by Sean Geldenhuys in ALOE 44.1:5, 2007 from apparently 2 populations in a confined area in the north and east of the Little Karoo. Placing it with H. emelyae simply reflects doubts that need to be expressed about how this oddity has come about, and respect lost for reasons not necessary to explain. H. truteriorum is described by Ingo Breuer and Gerhard Marx in ALOE 48.3:54, 2012 and refers to a single population of plants southeast of Oudtshoorn. That this latter population is singular and extremely interesting goes without question except for how it is explained. Despite much correspondence with both authors and after reading their published works, I am not aware that either has a concept of what a species is any different than what may have been held by either K. Von Poellnitz or G.G. Smith. Ingo Breuer particularly has published what he refers to as a species concept of Haworthia. This is nothing more than a long list of Latin binomials and we have to assume that this is then also a list of real species whatever they might be.  Gerhard Marx maintains that my attempt at a species definition is so broad as to be meaningless.  He has not supplied an alternative definition and I am left with the impression that he makes the same assumptions that “character” differences equate species as does the ordinary uninformed mortal.

H. truteriorum is described in a popular journal (Aloe) that has been approached by at least one botanist not to publish new species as there is no official review process. However, the response was that the journal does have its own in-house authorities that cover the possibilities of scientific lapse.  I note that the article is specifically foot-noted to indicate an editorial review and I perforce do not see this as a check on the scientific content.  There are some lapses that I will deal with but recognizing that these might not be the same ones that a properly qualified botanist (a minimum of a recognized 4-year degree course), nor those that an experienced and knowledgeable botanical taxonomist may have corrected.  More important though is the population itself and where it fits into the overall Haworthia picture.

The most substantial gain that we can make is to arrive at a species definition.  It is evident to me that species are complex systems in which there are variations that have arisen from to earth differences and must continue to exist to facilitate response. If there is evolution and thus adaptation and selection, then there has to be something to work with.   The phylogenetic idiom was “specialization is precursor to extinction”.   Geological and habitat diversity result in plant diversity.  This diversity is necessary for survival as the habitat changes. Therefore a species will have a geographic distribution across which individuals and populations will vary and be different from one another. Geology and geomorphology will be strong factors influencing plants like Haworthia that are associated with skeletal soils and rocky habitats. This means that we have to look for associations in respect of distributions and the driving forces that affect even vegetation. Thus in the case of H. marxii (known from 2 populations in a small area south of Laingsburg) the vegetative appearance of the plants cannot be seen in any other species geographically closer than H. emelyae, which is quite a long distance away southwards. The presence of H. pumila in the same area as H. marxii suggests that the Haworthia presence there could extend from the Worcester/Robertson Karoo. Hence H. mirabilis, also present in the Montagu area, cannot be ruled out in seeking a relation to H. marxii. There is much more to this issue of H. mirabilis in respect of its variability and its distribution into the Little Karoo that impacts directly on this suggestion. It also impacts on the real identity of H. truteriorum.

Where I see a real problem with H. marxii is in floral morphology. I gather that the flower very much resembles that of H. marumiana dimorpha. In the same way that the flower of H. pulchella globifera is identical to that of H. cymbiformis incurvula at Plutos Vale, there is a massive problem in drawing conclusions from flowers as a character for the level at which all role players are trying to identify species. But so-much for H. marxii and I do not seriously question it.

The case of H. truteriorum is more manageable. I have been speculating for a long time that H. mirabilis and H. emelaye may in fact be the same species. This may be the proper level at which we should be recognizing species as systems. I extend the argument even to say that it is not inconceivable that H retusa and H. mirabilis are one species. This means that I have to bury my long-held objection to the view that “Haworthia is a genus in a state of active evolution”. My objection being that this is an obvious aspect and that in any case all species are faced with the inevitable need for change and adaptation. But this does not weaken my view that species are chaotic fractal systems that vary around a point of attraction according to the stability of their genetic bases and mutating rate. How strong I am on the technicalities of DNA and evolutionary theory may be problematic, but there is no evidence that other authors even contemplate the issues.

Gerhard Marx is a remarkable observer and I have huge respect for his many skills. Breuer is a really competent compiler too. I do not question what they say about the characters of the plants and their observations.  What I question is their knowledge and insight into broader botany and the distribution and variation in Haworthia however much more they know than the above average collector.

My prime objection is that the description involves a single localized population. This in itself creates huge doubts in my mind because on this basis, Breuer’s several hundred species is conservative. I will only dwell on three other points. The one is their very trite “Never before have retusoid type Haworthias been found growing in shale in the Little Karoo”. The second point is the habitat description in relation to geology. The third is the flower and flowering time. The fourth is about the illustrations and the art work.

Haworthia mirabilis was recorded in shale at Barrydale by Smith prior to 1947. It was recorded at two places in shale or shale derived soils prior to 1999 and I can add that I have seen it at two new locations in shale in the Montagu area since. The second point is the description where it is referred to H. bayeri and H. emelyae occurring in quartzite and quartzite conglomerates. As in the description of H. groenewaldii, this is simply a very crude and inaccurate account of a very important issue. I am no geologist but I do know what quartz is and that it occurs in both shale and sandstone formations. Furthermore, I do know that the Oudtshoorn area has an incredible geology with ancient and recent geological formations adjoining as a consequence of faulting and folding. Quartz is Silicon Oxide and is apparently soluble in water at high temperature and pressure formation so that it can accumulate in fissures and bands in parent rock. In both sandstone and shale the quartz varies in purity, and the crystals in size. South of the Langeberg the shales are covered in an extensive layer of tertiary gravels that are far less extensive north of the mountains. But the main point is that the vast quartz patches of the Little Karoo are actually associated with quartz existent in the Bokkeveld shale. The “species” need to be properly looked at in their relation to that complex geology that exists there.  Marx and Breuer mention the differences north and south of the Outeniqua Mountains. But the Outeniqua Mountains are just an eastern extension of the Langeberg from the Gouritz River gorge. The geology north of that area is quite different from that west of the Gouritz. This suggests an ignorance of geography added to that displayed for the geology.

Checking my own knowledge and experience of the habitats of the species involved (viz. bayeri and emelyae – with the name picta an anomalous insertion), it is very clear that the statement “quartzite and quartzite conglomerates” is erroneous. There are four geological formations involved and these are the Table Mountain Sandstones, Bokkeveld Shales, and then Enon and Tertiary deposits. In the Heimersriver where the H. bayeri,  H. emelyae and “H. truteriorum” are reported, lacks Enon presences. The report of the plants in unfragmented, unweathered upright shale (Bokkeveld) needs to note that the quartz patches in the area are the result of fragmented and weathered shale.

Marx and Breuer perhaps should also take account of H. outeniquensis not a great deal further south in an area that I believe is still unexplored. There is also the mystery of a plant found by Avril Schein in that close area that remains unexplained.

We know from the H. retusa /H. mirabilis interaction that flowering time is no barrier to hybridization and that flowering time may not be indicative of a completed speciation process.  Ignoring the fact that we can only guess, on the basis of the scientific paradigm, that we are interpreting and trying to understand an evolutionary process. Breuer has attempted to jump this issue by the recognition of “aggregates” and the two authors use the fob of “the mirabilis/maraisii/magnifica complex. This complex I presume is explained as a list of names only. This I do think emanates from a mis- understanding of a real knowledge of field botany generally and of Haworthia in particular. I say this with great emphasis and conviction because it is something I am still working towards. I have just completed a very thorough look at a the flowers of a very small fragment of populations driven by the expressed opinions of both these authors in diverse places, that flowers are significant with the import that I have ignored them. The fact is that if the flowers are considered then we have a bigger problem than before – not a solution. The flowering time of H. truteriorum that Breuer and Marx cite is very possibly an indicator of behavior rather than a species differentiator. Why they emphasize it is most probably, as J Manning pointed out, most observers (taxonomists) have a subconscious belief that species are things that do not interbreed and so flowering time is seen as such a great barrier to interbreeding that it MUST be a major species indicator. My observation is that this is not true and that species are inherently highly variable systems with great capacity to respond to environmental drama that may threaten their continued existence. The nature of the problem is very well illustrated in the case of H. retusa and H.mirabilis where I contend that a fully developed view of the genus may require that they be seen as one species. Thus the importance of flower and flowering time is part of the myth of a non-existent species definition and is confounded by the concept Breuer and Marx have of the nature of Haworthia species.

There is a very good description of the flower and its character, but the illustration and the art work is weak. The photograph of the flower is of a single dissected flower to show an internal structure that could be of any species in the subgenus and is hardly helpful. That flower does not look to me like the perhaps longer narrower flower of H. mirabilis (real) which is largely recognizable on the arrangement of the petal tips in the bud-stage.  This ‘mirabilis’ character should be apparent in the way the petal tips display and we have only a painting to judge this by. Despite Marx’s craftsmanship I am not sure if his flower picture is a true image. I do have an observation on with his outstanding art. Many years ago, photography was a bit of a handicap when it came to illustration of floral and other plant detail. Historically artists were used to capture detail that could not be described or otherwise illustrated. In the present age this is a bit of a myth and it lives on simply because of the skill that is involved in the production of a good piece of botanical art. Marx’s art is up there with the very best.  But good art does not equate to good science? Or does it?  Botanical art is perhaps not the same as pure art and the intent of either may be quite different.  With pure art one could surely be trying to achieve the same goal as science and there must be some trick to understanding the similarity.

My conclusion is to plead for more rational classification and better attention to those things that matter. The fragmentation of a genus by Latin binomials just because of collector and novelty interests, aggravated by commercial implications however slight, is a disservice to all of us.

Previously published in Alsterworthia International Volume 12, Issue 2. July 2012.

I ask this question because too often the views of the collector are espoused as an excuse or defense for some or other argument about classification.  It has often been said to me that collectors are not interested in taxonomy and they are at the most, happy just to have a name.  This argument does not impress me because as a society we have a trust and a belief in science and whatever is written, outside of fiction, should seriously address the truth.  It should not matter what the reader may want to make of the product other than that the reader may just by chance really want to know and understand something.  On reflection, one writes for the reader who must surely be reading because they want to know something, and names are the key to the “something”?

This is why I have responded to reviews of my writing that have been published at various times.  I have written as a communication and am glad to know what the reception or rejection has been.  Recently Steven Hammer wrote what is listed under the title of “Book Review” comment on a recent book by Ingo Breuer and of Update Vol. 6 by me.  It is a wonderful piece of prose and worth every bit of reading and appreciation, but it does not pass as a Review.  Or does it?  I feel that it has a few mistakes as well as passing over the very real differences between the two publications.  So, I wrote a response in the way I treat any publication as an invitation to think and form an opinion; and express it.  Passing a draft of this response to a competent observer, I got this reply…” Fortunately, there is little expectation of a review. The point is: was the review positive or negative? Did the reader learn something and gain deeper appreciation, or not? Will they buy the book, or did the review satisfy their curiosity? For most readers, the details are unimportant, as much as you may hate this very concept.”

Why I should hate the concept of most readers regarding the questions of detail unimportant I do not know.  But I do think the accuracy, in respect of detail or general, is very important.  What my commentator was implying is that the review met the requirements that he was suggesting, and he added that my response was “nit-picking” and would only be seen as criticism of someone who is widely held in high esteem.  The fact is that Steven Hammer is also held in very high esteem by me and I am so glad to be able to say that he expressed to me personally that his “review’ was rather a literary fantasy.  What Steven does comment on is a view of the needs of collectors.  That they care little about schemes of classification and that labels are necessary irritants.  I do not question the truth of this view.  But would not accept that this is a justification for the imposition of just any kind of scheme because that is what a writer wishes to propound for reasons of his /her own.

These then are the points I made in my response that I think Steven should have addressed.  The ‘mistakes’ are … a). The Audensberg population was actually shown to me by Elsie Esterhuizen many years ago and it is not the place where any haworthiophile  would ordinarily look for plants. b). The reference to Drosanthemum bellum is odd because Steven describes this as a “niche-sensitive species”.  This “species” is at the heart of a very long and detailed story of Drosanthemum micans that I once wrote and lies unpublished.  I would surely have used this as an example of the way in which botanical science has also failed us.  D. bellum is a pink flowered variant in a much-localized population of D. micans that also has white, purple and red variants.  This tiny population sits among a larger widespread population of yellow flowered variants that go by the name of D. hallii.  This is turn has variants that include the typical bi-colored flower of the older D. micans that is common north of Worcester.  Further variants occur north-east of Montagu, to Oudtshoorn and then south to Mossel Bay (D. edwardsii) back west to Bredasdorp, (D. lavisii, D. aureopurpureum and D. croceum?).  The problem here is the failure to establish what is meant by “species”.  To refer to D. bellum as a species is a misconstrual of science, or an example of the liberties that are taken with Latin names – botanists and collectors alike. c). Chameleons.  Wonderful words of Steven’s, but not quite complete.  The story about chameleons’ parallels that of the very low non-tech problem of impossible identification even when there are heaps of “characters” to use.  It fortuitously exposes the probability that we are being led up a garden path by high-tech.  I have used chameleons in the same way that I studied Oxalis ultimately demonstrating that species are complex systems of variables! d).  Kaboega is not the only area I know exceptionally well and it also figures in practically all the other volumes of Updates of which there are five.  I doubt if these have ever had much coverage, but they are an account of my voyage of exploration and discovery that is the concern of mine in respect of omission.  In the Updates I discuss the populations and their variants as they occur at many different places and show this impact on the application and use of Latin binomials.  There is a prevailing misconception that this is only a problem within Haworthia.  I show that this is not so.  I also make several references to the fact that Haworthia is by no means an integral single genus and that the nature of genera in the Alooideae needs proper attention based on a lot more than the fact that the Haworthia subgenera have small flowers. e) “Shaggy dog” for H. mirabilis Ballyfar is not a name I coined but Steven himself.

I do think the omission is in the comparison of the books where there is in fact none.  My Update Volumes revolve around the way that science has let us down to the extent that any pretender can take up the mantle of taxonomic expert.  Botany provides no species definition and hence the Latin binomial is not required to carry any meaning other than a guise of authority.  Whatever collectors may require has no import whatsoever in a process of classifying plants as biological entities.  They are focal points for the collection and storage of knowledge indicated by Latin binomials and these are not simply and only intended as labels.  Even I recognized this as a child when I wanted to know what the plant actually was that my father called H. chalwinii, and where it came from.  Every collector who refers to names at all surely expects and believes that there is some mystic or real knowledge associated with the names he is given and uses.  It is an injustice to any collector to coin Latin names outside of the context of science where the collector is entitled to believe they belong.

  The only predicable thing about Breuer’s system, which is a watered down version of a much more focused and detailed one by Hayashii, is that there are going to be a lot more names.  This is not only when someone else climbs the Audensberg, or recollects the Sandhills population, or drifts across into the Heatley Peak area.  Throughout the Updates, I warn and demonstrate that character fixated taxonomy may be very misleading.  Vavilov was a Russian botanist who pointed out that variations in a genus may be expected in all the members of that genus.  Species are therefore to be seen as systems that are natural assemblages of plants that can be associated in respect of ALL the forces, factors and features that generate them – not propagules of single clones that fill availability lists and price catalogues.  Drosanthemum bellum is just such an example of how Latin binomial names are used to describe variation within species, rather than to properly organize the basic entities that make up the entire living system.

I have, even in the Updates, shown how the watchdogs of science let us down.  I have tried to communicate my experience and observations to a wider and expectedly interested audience.  This, in the hopes that it would lead to greater understanding and comprehension of the problems of finding names as the backbone of communication, appreciation and understanding.  It is a huge disappointment to me that I have achieved very little other than to grow wiser myself.  One of my many critics makes a show of taking up middle ground between me and other Haworthia taxonomists.  My response is that taking up middle ground between myself and the ignorant is not going to be very productive.  In the first place there is not much space there as I am quite aware of my intellectual limitations.  In the second place I have not actually been all that certain that my overview is entirely correct.  Despite being credited with a lot of field work (and no good sense to go with it) I am extraordinarily aware of how much I have not seen.  This adds to my discomfort as I see a proliferation of new names, gaily forgetting the multitude that I moved aside in my Revision.  These are often based on propagules from my own collections (concealed by the creation of new collecting numbers that are not mine).  I recognize that the only predictive element in this kind of science is that we can expect many more Latin binomials in a collector driven system rather than one of botanical science.  So indeed I see no change from the failed methodology of Von Poellnitz, Smith and Scott.

There is no comparison at all between the two books that a true review might have suggested.  One book (Breuer) is a collector’s guide to a limited range of variants (albeit 336?), while the other (Bayer) is an account of a very wide range of variants and a hypothesis (not a statement) of how they are related.  The latter also throws some light on the universal quandary knowledgeable observers soon come to experience viz. Elton Roberts in the same edition of the Journal where he questions the identity of Mammilaria lasiacantha.  The problem he has is a classification fixated on superficial small differences rather than one based on the realities of the variation that should be expected in any system arising from, and actively responding to, differences related to time and space.   The essence of science is that an experimental method is applied to a sample and repeated, the result will be the same.  If everyone is coming up with a different plant classification, it should occur to us that there is something wrong with the method and perhaps also the hypothesis that is being tested.

I am curious why my commentator dismissed all the above as “nit-picking” when myself I feel that they deal with the most significant elements of writing at all.  Especially, they touch on the very core of why we even classify and name plants in the first place.  My response should not be seen as a criticism of my commentator, or of Steven, a remarkable man who is also very dear to me.  I also respect him enormously for his empathy with plants because if there is anyone who projects my view that this is a conscious creation all the way down to its rocks, it is him.  There is surely purpose in creation if only that we should seek and find what that is.

The article by Gerhard Marx in Haworthiad 26.2:41 is really excellent. There is however some behind the scenes innuendo as well as repeated use of words like ”ignored” and “neglected” that need attention. There are furthermore comments on “substantially different and unique characters”, “forcing” elements into synonymy and use of words like “truthfully” and “knowledge of the genus” that distorts a reality that is historically under stress. This is totally unnecessary in an article that otherwise contributes so much in the real area of interest and information.

What we first could deal with is this vexing question of what science is and who is a scientist?  In the issue of Haworthiad the editor feels it necessary to state that he is not a scientists and both Al Laius and Stirling Baker imply that there are things that the uninformed dare not comment on.  Let me make it clear that most of the writing and classification of Haworthia has been done by authors with no formal training in biology whatsoever.  I could fill the whole of an issue with detail of how trained and experienced botanists (scientists) have made mistakes in their small contribution to our “knowledge of the genus”, or simply confounded it.

What the Gerhard Marx’s article actually does is ignore history and written knowledge of the genus.  He does profile himself on Facebook as a “succulent botanist” but I doubt if this meets the South African Association of Botanists requirements for membership.  Many taxonomists have not been scientists at all, and one cannot fault the enormous contribution that most ordinary people (education-wise) have made to botany. So who am I then?   With an MSc and a thesis on morphology and taxonomy, am I a scientist?   Does training and a formal qualification mean anything at all?  Am I really just another writer?  Perhaps not.  But…

My first bone of contention is the use of the word “ignored”.  This is because it is combined with the notion of unknown transitional elements.  This is plainly misleading and incorrect.  Von Poellnitz described H. mirabilis ‘beukmannii’ as a variety of H. emelyae probably as the first clue to some sort of transition between elements south and north of the Langeberg and Outeniquaberg.  Von Poellnitz cites several specimens from north of the Langeberg that he confused with H. pygmaea and what I later recognize as the totality of H. mirabilis.  As long ago as 1976 I published a map in Excelsa, replicated in my Updates, to speculate on the transition of the southern retusoids into the Little Karoo as far as Steytlerville.  In a recent treatise available to all I explained the remarkable similarity that I perceived in H. pygmaea  in the Herbertsdale area to H. emelyae a relatively short distance away north of the Gouritz Gorge.  Many years ago and lost in my writing is the extraordinary similarity of H. emelyae ‘major’ and H. mirabilis ‘paradoxa’.  While surely there must be a record there too of the extraordinary similarities that I observed of H. emelyae ‘multifolia’ to H. mirabilis ‘sublineata’ as well as to H. mirabilis ‘heidelbergensis’ and even to H. rossouwii.

As an aside I must just draw attention to Al Laius’s comments on what he refers to as H. heidelbergensis and H. magnifica.  This is because Marx also uses names like átrofusca’, ‘magnifica’ and ‘mirabilis’ with no appreciation of the realities of these names.  This brings me to the second bone of contention – the one of “neglect”.  One can only do so much, and if Marx can concede that then he can approach this from a more objective angle.  I have been fairly limited by opportunity and finance apart from the enormity of the task, but I can and have pointed to a multitude of situations that are no different from the area in the Little Karoo that Marx has easy access to.  I have not felt it necessary to venture there where activities of collectors and others have made it too often to ask the indulgence of landowners.  Also, when there is just so much else to do.  But one of the situations I must refer to is that of the “species” H. groenewaldii, the description of which was also instigated by Marx.  The explanation of this taxonomic deviant occupies almost all of Haworthia Update 7 that is available in hardcopy and also on the internet.  This explains some of the aberrations that filter through to Marx’s article.

Does that bring us to the question of “substantially different and unique characters”.  My MSc thesis had as the subject the nature and significance of complex morphological structure – albeit in entomology.  So I actually do know a little bit about characters.  I also know a little bit about the use of DNA strings as character sources.  More practically is the work that I have done in respect of characters in Asclepiads, in Drosanthemum, especially in Oxalis and even in chameleons.  A scientist unfortunately cannot restrict him- or her-self to what they think are the realities in one small area.  There is far more to life than Haworthia and it does not have any special problems.  There are any number of substantially differences and unique characters even in individual plants.  Marx throws this all away with a rather mixed final sentence and reference at the end of it to a “very consistent set of measurements”.  Stephen Gould once said that the strongest statement that one could make in biology was “hardly ever”.  A consistent set of measurements in biology is spelled out in the science of statistics viz. biometry.  Perhaps that article by Loucka and myself dealing with the statistics of H. mirabilis ‘sublineata’  needs to be unearthed. Some variation in Haworthia mirabilis var. sublineata

So this takes me to the other bones of contention viz. “forcing” “truthfully” and “knowledge of the genus”.  I have written elsewhere that the taxonomic system is at fault, and I will not even try to defend that simple statement.  It is.  One of the difficulties is that things that are neither here nor there have to be unequivocally assigned to a taxon.  If this is coercion as Marx implies, then he is unaware of a very self-evident truth.  There is no place for the chemical equilibrium equation or the subtle variants that Marx even describes.  The sorry fact is that formal botany and the ICBN does not actually provide for “aggregates” and this is just a ploy to evade the issue of the definition of “species” and what it truly means.  Manning as a professional botanist needs more than ordinary opinion, in a very small field of interest, on which to base a formal list of names for a national catalogue of 23000 names.  To treat each genus in that list on the basis that Breuer and Hayashi have done would be unthinkable.

In closing we have this fudging statement…”Haworthia will remain a taxonomical argument problem for many years to come”.  It surely will when writers, editors and readers prefer the mileage they get from disagreement instead of properly informing themselves and working actively towards a common goal with “truth” as a commitment rather than as a word to discount what is already suggested.

In An honorary Ariocarpus in Africa – Notes and updated information regarding Haworthia marxii (Alsterworthia Intenational Volume 12, Issue 2) Gerhard Marx and S. D. Gildehuys respond to the inclusion of H. marxii under H. emelyae  by Manning and Bayer in the Rationalized List of Names.

The reason for my dumping H. marxi was purely political as I explained elsewhere. It is just my opinion that there were and are shortcomings in the author’s whole approach to names in Haworthia. So I expected some attempt at vindicating themselves like this. I have no problems with considering H. marxii as a species. I would simply prefer that it remains an element that desperately requires an explanation.

My problem is with statements like this …”Typical H. archeri can be found only … at Viskuil (JDV89/62)”. I described this species and from where it occurs at Ghaapkop and at Baviaans Station just east of there (and Viskuil is just a few miles further east). I later placed it with H. marumiana because of several other oddities widespread and also because of the very wide distribution and variability of H. marumiana. I have since found it also at Lospersberg. Marx has previously been on at me about the relation of H. archeri to H. marumiana. I did not realize that he was unaware of what actually constituted the knowledge of either species.

There is also mention of a collection of PVB1405 as from 20km SE of Rooiberg Pass. This is a bit of a mystery to me as I thought I had noted this collection of PVB from east of the Floriskraal Dam and was for a long time the only possessor of the single plant in cultivation. This collection is cited in my Revision as are the two “archeri” collections noted above. I am sure I noted this collection 40km ESE Laingsburg. It is a mystery because it is north of the Witteberg and Swartberg and is tied in with another population that Bruyns recorded at Baviaanskloof. Every indication is that it is connected to a population of mine at Scholtzkloof, Prince Albert; and so with things that I pondered may be a marumiana connection i.e. ‘var. viridis, or even connected to monticola or more probably, H. vlokii.

Another statement I must make is about the significance of flowering time, as the evidence is that it is not as meaningful as the authors imply. There are hybrids and population evidently arising from hybrids in these interactions – retusa/mirabilis, mutica/mirabilis, floribunda/pygmaea, floribunda/retusa,and herbacea/reticulata. The latter is not across a seasonal flowering difference but the others are.

The large gap between Montagu and Rooinek Pass is reduced somewhat by the old populations of H. mirabilis northeast of Montagu at Dobbelaarskloof and by the new population recorded near the Pienaarskloof Dam. Also relevant is the distribution of H. pumila. So maybe exploration has simply been inadequate. I was and am fully aware of the distance issue.

Regarding flower morphology. Similarities in the flowers of otherwise very different things, is just as significant as differences in the flowers of things that may in fact be very similar. So these small differences should not be punted without far more attention been given to what actually constitutes difference. The few pictures of the flowers that are provided are hopelessly inadequate to base any opinion on. The ultimate issue is that the authors are using idiom, method and logic that have been in service since before Von Poellnitz, Smith, Scott and the rest of us. It has not worked. It is not going to resolve the complications we can find in situations like between say H. mirabilis and H. retusa, or H. arachnoidea and H. mucronata, or H. cooperi and H. cymbiformis, or H. cooperi and H. bolusii var.blackbeardiana. To name some of the more obvious interacting species or elements if we do not know what species are.

Preamble: Maybe the difficulties and strife in Haworthia classification is that we do not know what it is that taxonomists do. Taxonomy is the academic discipline of defining groups of biological organisms on the basis of shared characteristics and giving names to those groups. The scientists that do taxonomy are called taxonomists. The names taxonomists give to species don’t just tell us what they are called, but also tell us about how they are related to one another. In the following article Bruce Bayer shares his views that Haworthia taxonomy should be about more than identification and descriptions, rather the interpretation of the characters that reveal genetic relationships and evolutionary pathways. ~ Lawrence Loucka, 7 September 2012

Genetic  history – the place in Haworthia classification.

By M. B. Bayer

This is a huge subject and I cannot by aptitude or knowledge attempt to cover it fully.  However, it is so basic to plant classification and Latin naming that we all need to have some background understanding.  The entire object of classification boils down to arranging living (and once living things) in a scheme that follows the theory of an evolution from simple life forms to the present array of creatures.  This is because it is thought to be the logical way in which knowledge of the said creatures should be organised i.e. according to the way in which they traveled the creative way.  All classification is simply a way of organising information so that one can generalise from the singular to the plural.

Whether one believes in such a progressive process or in a spontaneous divine creative event does not matter.  All the evidence points to change of some kind and if we call it evolution does not alter anything.  It is argued that there is in fact no direct proof that, say, man evolved from a primitive primate.  That may well be so, but there are many fossil primates that are speculated to fill that gap. The case is that evolution is a scientific hypothesis and science does not, or cannot claim, that this is proven.  A scientific hypothesis simple stands as a possibility or probability of something known.  Such a hypothesis can only be proven untrue, and then it is replaced with a new hypothesis that stands as the accepted truth.

Whatever, the ultimate truth of the matter, classification in science is directed at reflecting how the different life forms are related to each other in respect of change?  In the acceptance of evolution the process of change is the genetic history of the organisms and is referred to as the phylogeny.  It is often depicted as a branching tree with the branches originating low on the trunk as ancient origin, to terminal branching for recent.

My experience with classification comes with education and qualification in entomology (insects).  It so happens in insects (and higher animals) that there are many characters and structures that can be used to examine the process of change and modification that might go with evolution (change).   The word “homology” is used.  So, say, the wing of a bird is likened to the forelegs of a dog – they are said to be homologous structures.  The change in structure from that of a segmented worm (eg. Onycophora) to say, a wasp, can be tracked through a whole range of insects.  The head of a wasp is seen to be derived from 6 primitive body segments, the thorax from three, and the abdomen from several.  There are muscles and nerve endings and sub-segments that are all evidence of these connections.  In entomology, there was a stage when a qualification in insect classification required the student to also present a phylogenetic scheme to explain relationships relative to an origin. This all based on morphological characters, their homology and their interpretation as primitive or advanced.  What is really odd is that too often a classification comes to deny the variability that a concept of selection and adaptation that evolution rests on, is denied.

In plants there is no luxury of musculature, or nervature or even detailed bone or segmented structure on which to base good homology.  Botanists are therefore very hard-pressed to properly derive phylogenies or explain this genetic history.  Nevertheless a very serious and honest effort is done to do this.  The process of cladistics was derived from entomology (Hennig) and became the standard for the student in botanical classification.  Students were required to evaluate characters on a basis of primitive and advanced, and construct cladograms that illustrated a hypothesized process of evolution.  The advantages of the method over conventional decision making were that it is said to be an objective way of arriving at a conclusion rather than personal subjective decision making.  With the complaints against my use of words and language, it is worth noting the remarks of a leading botanist who said that the methodology of cladistics was just the use of a new language that did nothing more than strain good-will.  Agreed.

With the arrival of DNA sequencing, a whole new ball-game was created with each amino-acid base pair representing a character.  So DNA sequencing has become the modern standard for the construction of phylogenies and genetic history – the phylograms.  So much so that the article in Taxon 56:645-648, 2007 by A.B. van Wyk argues that the phylogram represents the process of phylogeny as the genetic history as opposed to the cladogram that attempts to construct the genetic history.  I personally think that this is intellectual wizardry and the literature references in the Taxon article only expose the mystery that surrounds classification.  It takes classification wholly out of the reach of any but a polymath.  Basic to the whole issue is that scientists still have not reached any certainty about what a species is.  The theory of evolution is not disproved.  Van Wyk has said

Plant taxonomy, despite all its impressive achievements towards phylogenetic reconstruction, will then risk being denoted as yet another ivory tower science – a pursuit disconnected from the practical concerns and needs of everyday life, esoteric, over-specialized, its classifications of little practical use to the majority of end-users”. 

It sounds very impressive, but I weep for the fuel that it adds to the fire of ignorance.

What truly appears to be the case to me is this.  To construct a cladogram, the taxonomist needs to be very familiar with the plants and have a good understanding of the characters being used in the process; adjudging them according to some scale of advanced or primitive.  The DNA sequencing method requires no knowledge of the plants at all and a phyllogram simply follows a statistical analysis of equivalence of the base pairs.  What I see is DNA derived products that so far tell me no more than I already know about the genera, and nothing at all about the species other than some serious mismatches.

I argue for a species definition, not as some vague statement that species are things into which a genus can be divided, or simply a list of names under a Latin genus heading, or the zoological concept of closed breeding systems.  My definition drawn from a lifetime of interest, observation and experience in things material as well as esoteric, is that the creation is a conscious one.  This is not a new idea of mine.  The conflict between religion and science is that the one maintains that creationism followed some sort of seven day event as in the book of Genesis.  Whereas science (as we practice it today), has its origins in the quest for freedom from any such religious belief system.  Whether creation began as a big bang, and complete or incomplete does not matter to me.  We are faced with natural phenomena in the present that we can observe have changed and are changing.  I do not think either the cladogram or the phylogram is anywhere near good enough as an answer, because they are two-dimensional diagrams that do not adequately portray the realities of time and space.  Not only that, a three dimensional improved tree model will not show how fast things change within a time span.  My model of the species tree is a fractal model that suggests species in a process of “chaotic” order.  By the word fractal I mean the endless variation that seems to have no order.  While I insist that the concept of a species of Haworthia must mean the same as the concept of a species of insect or frog, or bird or mammal, I do not mean that each species of Haworthia has the same branch clarity on any tree depicting relationships.

What I do not know is how fast populations might change in the process of genetic drift i.e. move off in a direction determined just by the local genetic content.  Neither do I know how much nor how frequently interchanging of genetic material between populations occurs and how this is affected by distance between them.  In the field there is a very distinct flow of difference (or similarity) with geographic spread.   I have repeatedly found that with widely separated known populations, new populations between them are predictably intermediate.  It does not seem entirely rational that there are not more random isolated individuals.  My experience with hybrids is that they are very local to the mother plants while any populations tend to be very confined and local.  What is odd is that hybrids may be found despite great differences in flowering times of the parent species.

The reality in Haworthia, however we define species, is that there are populations that are neither one taxon nor another.  If the classification were to present a basic requirement that ALL populations known and unknown must fit the model, then definitely we have to consider that there are considerably less species than other writers are prepared to consider. One can continue building a classification from the top in which each new population is simply described as something new and given a Latin binomial. This process was suited to the origins of botanical exploration as well as nomenclature. It does make it a lot easier for collectors and the exciting process of always novelties for the collector.  Alternatively one can decide that classification is by this stage a fully predictive one and one that must primarily suit the requirements of botany. If only botanical classification was more professionally and rationally based.  Sampling is very extensive and a classification based on the known, is predictive.  Personally I am very comfortable that I have achieved this in large measure – not entirely, but close enough and a lot closer than some critics will concede.  With all that said and done, it is just a sad fact that formal classification is too often undertaken by people who have a need.  That need may satisfy them within the limits of their personal experience and knowledge, with an uncomfortable disregard for the depth of knowledge elsewhere.

Reference:  Readers can refer to the article in Haworthia Update Vol.2:149 (2006) “Nectar sugars in the Alooid minor genera and a need for another model”.  That article is also posted to the internet with much of my other writing in HaworthiaUpdates.org.