Table of Contents

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Kaboega

Kaboega is located in the Zuurberg Mountains north of Port Elizabeth in the Eastern Cape province of South Africa. Read more about this in Haworthia Update Volume 1, Chapter 5:- The Haworthias of Kaboega. There are a mind-boggling array of Haworthia populations here in an area considered to be the meeting point of several vegetation biomes. There is much exposed rock, and the soil is very skeletal, composed of three major groups: sandstone, mudstone, and glacial deposits. These pictures are of a Haworthia cooperi variant that occurs high up on sandstone. I went to this spot because researchers had sent me a picture of a cycad festooned with Haworthia. I did not get to the exact spot but have seen the way it forms hanging bundles in other situations.

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Haworthia glauca!! can also be found here. On Kaboega these plants often have a very close resemblance to H. coarctata and it is no co-incidence that the distributions of these two species complement each other. An essential element of species recognition is their juxtaposition and if they occur in very close association or not. Darwin said as much.

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I visited four populations of this greenish cooperi. One can find plants like this from east of Grahamstown right through to the Little Karoo. Here they are on Dwyka (glacial) skeletal soil.

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These next are in the shales low down in the valley on Kaboega – I name it H. aristata. It is very common in the area but complements H. cooperi while there are populations that are neither. Populations cannot be treated in isolation and there is a distinct possibility/probability that I have been too generous with species. The attempts to find answers via DNA sequencing should make the vendors of that technology thoroughly ashamed.

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More of these green things. I would guess that these would class as the simple progenitors of cymbiformis and cooperi. Perhaps even of mucronata?

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This is Haworthiopsis sordida that does not occur, as far as I know, north of this. H. nigra also occurs here at it’s most southern at this longitude. Altogether it is quite a complex network of distribution patterns that relate to greater plant geography.

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From another population as variants on a theme. have seen about 30 such just on this small mountain area and it just suggests what is still unseen on the length and breadth.

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Not a great diagram but a way to appreciate the drammatic choreography of plant distribution and how it impacts on classification. Without it Haworthia names make no sense other than as imagined and fantasized. Cooperi and cymbiformis occur as intertwined species to the east and south. In the south they extend westwards to get lost in H. mucronata. Cymbiformis as an independent species does not enter Kaboega except as an observable variant of H. cooperi. The cooperi gets lost westwards as variants of H. decipiens. Perhaps close northwards as H. aristata. H. glauca does cross the Zuurberg but is here confused with H. coarctata that may occur in recognosable form on the eastern tip. Angustifolia is on the eastern end too but does not enter Kaboega. Neither do H. monticola or H. zantneriana from the west. This is also closely tied to the intrigue of winter vs summer rainfall and still further to the massive geological changes of the very recent..

k map

Zuurberg

What do you think this is?

what A3 what A1 what A2

Incidentally both the soft shale bands within the Sandstone strata as well as the Bokkeveld Shale above, decompose to kaolinic clay.

what C10 what B1 what B2 what B3 what B4 what B5 what B6 what C1 what C2 what C3 what C4 what C5 what C6 what C7 what C8 what C9

I took so many pictures that I will just post because I was so fascinated myself. The population is in an area quite new to me and wholly empty as far as haworthia records go – but perfectly predictable if you throw out the chaff. In the meantime, keep thinking.

The plants were all in much the same situations among sparse restioids and grass and very few other succulents. Next I will post better pictures of a few plants and explain a bit more.

what D13 what D1 what D2 what D3 what D4 what D5 what D6 what D7 what D8 what D9 what D10 what D11 what D12

What do we have so far? Mirabilis, ‘magnifica’, atrofusca, pygmaea, comptoniana, esterhuizenii, Quite good actually – but some serious omissions. Any more offers – these are all excellent.

Just to make sure the name “magnifica” makes sense, here are a few pictures taken at the type locality.

magnifica 1 magnifica 2 magnifica 3 magnifica 4 magnifica 5

While looking at those magnifica pictures I was struck by these two to show how a retusa influence is present.

R1 R2

A closer look at the new find.

what E6 what E1 what E2 what E3 what E4 what E5

The scenery

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Those flat top hills are the remnants of an ancient african plateaus prominent from near Barrydale to beyond Uniondale – north of the Langeberg. – silcrete upper layer like the concreted layers also present topping the inselbergs south of the Langeberg.

So what is it? If H. magnifica makes sense to anyone as a species, that person is lost to me. This new population is in the sequence from Muiskraal eastwards and it is H. emelyae (‘breueri’, ‘wimii’). The identifications put forward are nearly all in the context of H. mirabilis which includes ‘magnifica’. This naturally supports my perceptions that H. emelyae is in fact the karoo extension of H. mirabilis. More widely that H. mirabilis, pygmaea, retusa and emelyae form a single system. If one reads in the Updates the reports of Towerlands/Aaasvoelkrans one will appreciate the connection better. The “magnifica’ as a species myth is simply and easily dispelled by studying the floral data presented in updates. There is no reason why there should be any doubt and confusion that the cabal so enjoys and wallows in. Aloe barbara jeppeae indeed.

The truth of the matter is that there is no taxonomic solution other than recognising this and stop prostituting science in the name of populism.  There are hundreds if not thousands of people interested in Haworthia, and millions affected by the formal names of plants. I see some responsibility in respecting this fact and even more so in trying to understand what all this marvelous stuff really means. It comes down to what a species truly is and how it is defined. If I could bring just one person to that realization I might feel comfortable – with no one caring a damn, I am not. :) I have not far or long to go now and I will be posting more on this topic before I am finished.

M.B. Bayer
June 2016

Leaf sequence in Haworthia emelyae ‘comptoniana’ over a long period

Leaf sequence in Haworthia emelyae ‘comptoniana’ over a long period

1 December 2011 16 July 2012 15 September 2012
13 December 2012 13 April 2013 August 2013

Here is an interesting series of pictures showing Haworthia leaf replacement over only 16 months.  The plant is in an outdoor rockery.   Leaves are numbered from oldest to youngest.  Leaf loss has not been quite sequential as the 7th leaf outlived the 5th.  In the growth condition of September 2012 the leaves show three tiers viz. 1,4,7,10,13 / 2,5,8,11 / 3,6,9,12.  The figure for Dec 12 illustrates the “5-tiered” artifact of the spiral sequence with leaves 15/10, 14/9, 13/8, 12/7 and 16/11/6 in each tier.

These pictures demonstrate that the plants grow quite fast.  They may not be very long-lived in nature.  I estimate a life span of 15-20 years?

The first picture of this plant was taken in Dec 2011 when the leaves were numbered 1 to 10. Here in March 2014 leaves 1 through 12 have died away and there are 10 new leaves. At the same time the stem will be stretching as roots are replaced in a similar sequence. The life of the plant is going to be determined by the way in which the old stem and roots decay and how that decay will affect the ultimate health of the whole plant.

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In the field it seems as though the decay of the old leaves and stem is well regulated as a sort of dry composting. In cultivation this can vary from this state to when all the roots and even the base of the stem can rot unhealthily. In the field one does finds moribund old plants that are at the end of their life and with large aged stems. Just how long the plant can maintain good health in either the field or in cultivation is an unknown. A grower just has to depend on experience and feel for his/her plants and this is why some time back I guessed at the normal life of one of these ‘retuse’ haworthia at about 10-15 years. Some things like T. pumila and H. coarctata are quite different as the stems can elongate and re-root along the ground. Plant of H. coarctata more than 3meters in diameter must be very old. Even H. reticulata or H. herbacea do this – look at H. cymbifomis ‘ramosa’. What you can consider is that new leaves and flowers follow a regular process and it is useful to remember that the plants go through a non-growing stage in the year. I tend to think most haworthia grow in the spring and autumn disliking the heat of summer and the cold of winter. But this is just a generalization that points to things that need to be considered. All species are not the same. Good root health is also associated with drainage and adequate air space in the growing medium.

In species like coarctata and reinwardtii – and I doubt that these are two different species – the plants easily lose obvious connection to the mother clone and a single clone can come to occupy a very large area. H. cymbiformis and H. angiustifolia can also spread widely by pieces breaking off to establish somewhere else. H. limifolia does it by stoloniferous expansion as can H. marumiana and H. zantnertiana. But coming back to the solitary non-pupping growth forms it would be interesting to know just where the essential life of the plant resides. Sometimes the stem just seems to get too thick and cutting it back too far also cuts away the support and source of the very young and new centre leaves.

 

Variable chloracantha

Variability – sounds so hackneyed now but still it does not seem as if anybody “gets it”. These are plants from two populations of chloracantha east of Herbertsdale. Two very different soils. One is shale and I show only a single plant from there – the left one of the three unearthed plants. There the plants were “ordinary” chloracantha. But the other locality was exposed “pressure burst” kaolinite such as you get around Riversdale and westwards. Some of the plants reminded me of floribunda and even parksiana. I know of only 6 populations around Herbertsdale and there the plants are different too.

7866 H. chloracantha. E Herbertsdale 100_7472 7827 & 7866 H. ch;oracantha. Herbertsdale 100_7505 7866 H. chloracantha. E Herbertsdale 100_7458 7866 H. chloracantha. E herbertsdale 100_7459 7866 H. chloracantha. E Herbertsdale 100_7460 7866 H. chloracantha. E Herbertsdale 100_7461 7866 H. chloracantha. E Herbertsdale 100_7462 7866 H. chloracantha. E Herbertsdale 100_7463 7866 H. chloracantha. E Herbertsdale 100_7464 7866 H. chloracantha. E Herbertsdale 100_7465 7866 H. chloracantha. E Herbertsdale 100_7466 7866 H. chloracantha. E Herbertsdale 100_7467

The absurdity of taxonomy and nomenclature?

In Alsterworthia 13.1:6 (2013) there is yet another statement about the correct name for a species of Haworthia.  It reads …”The vexing matter of the correct name for Haworthia pumila has taxed some of the finest minds in botanical nomenclature”.  The article then goes on to replace that name with H. margaritifera with an explanation so simple that it casts considerable doubt onto the quality of those minds that have examined the problem.  There is of course also a difficulty in that the quoted sentence implies that H. pumila is the correct name, while the article goes on to dismiss it.

The fact is that Linnaeus listed four different things (varieties) under a single name Aloe pumila, and the only issue was about which of those four things ends up with that particular first name.  It so happened that Burman in 1701 made a choice, and was followed by Aiton in 1789 who chose something else.  So the name Aloe pumila stood but applied to two different things (species).  Duval was unaware of the earlier Burman choice and used Aiton’s choice when he created the genus Haworthia.  Dr L. A Codd, whom I would have accepted as a fine mind (and also as a very ethical man), advised C.L. Scott that Aiton’s choice was in fact illegitimate and hence also Duval’s usage in Haworthia.  The opinion was that Burman’s choice was the first and also thus the legitimate one; and it could not be denied by the illegitimacy of the Aiton usage as a later action.  So perhaps it was/is a question of rank or just an opinion that Aiton made up pumila as an entirely new name.

There is nothing complicated and mind boggling about this simple state of affairs.  Or is that so?   What on earth does the ICN as the product of presumably fine minds actually say about this?  Does it take 50 years of debate to establish such a simple fact?  The situation is further exacerbated in that the finest taxonomic minds are involved in an epic battle to either create a single alooid genus or many lesser genera.  It appears that the latter option is winning ground although the war against single-species genera has surely not been abandoned.  When the dust finally settles, it will be recognised that the taxon onto which this unfortunate species viz.  Haworthia pumila/margaritifera resolves, will be a separate genus, probably Tulista, and then the truly correct name will be Tulista pumila.  Or will it?

My personal opinion that however the case may truly be judged, the correct answer is the intent.  Scott and Codd came to a workable end point way back in history and it has been my misfortune now to have defended that.  I think there is a parallel in the case of Aloe bainesii.  Put into use by Reynolds far back in history, it is found that the name barberae had page priority and thus preference.  In what interest was the change made?  Why does the code have a conservation facility for names?  The fun seems to be in the argument rather than in usage.

The argument that I think L.A. Codd would have made is this.  There are four varieties covered by the Linnaean epithet pumila.  The first effective use of that epithet for one of the four was to the warty t10 of Commelin and that is how the name is formally typified.  To use of that same epithet at any other time for any other of those four Linnaean varieties would be illegitimate.  It is also not in the least certain that the name margaritifera is correctly typified by Wijnands on the same Commelin illustration t10.  I aided Wijnands to this conclusion before myself stumbling on the fact that its correct typification would be on a Bradley illustration.

There is a curious twist to the issue and it is somewhat of an oversight that the persons involved never read the introduction to Haworthia Revisited.   I explained the problem and also in respect to the correct application of the original name margaritifera to what we know as H. minima.  I also cited the name H. pumila with the authors as (L.) Bayer to make it clear that I was not accepting the name with the authors (L.)Duval as Scott cited it.  I thought at the time that it was a mistake on Scott’s part.  I had also written to Dr Codd specifically about the issue and this is when he explained to me (as a professional taxonomist and fine mind) that the illegitimate use of the name pumila in Haworthia did not prevent the correct usage.  It only strikes me now that he probably had advised Scott to the effect that the NAME as Duval had taken it through to Haworthia was correct, even if he had applied it to the wrong species.  This whole issue has not been properly and fully aired.  To argue that it is a new name seems to me just a piece of intellectual vanity that serves no purpose other than to demonstrate our collective failure to honour the intent of the code – or respect the dismay of interested person.  A last point I make is that people can and will always find topics to disagree on, so this is an important trap to avoid and be mindful of.  It is not particularly in the case of nomenclature that this seems to happen.  I had no doubt at the time when I made the decision to accept Scott’s usage that no matter what my decision was, cause would be found to change it.  If I had decided on either margaritifera (correctly typified) or maxima (as I. Breuer later did), this would also have been argued as wrong.

[-ed. There seems to be a number of taxonomic changes brewing.  Time will tell whether pumila survives.]

References:

1. Haworthia margaritifera/pumila
Dr. John Manning. S.ANBI.

The vexing matter of the correct name for Haworthia pumila has taxed some of the finest minds in botanical nomenclature. Since I do not include myself among their company, I was not in the least surprised to find that I had misrepresented the situation. Thanks to expert input from Roy Mottram and Urs Eggli we can now put the matter to rights.

The issue of the correct name for Haworthia pumila starts with the fact that in his original publication of Aloe pumila, which forms the basis for this species, Linnaeus recognized several varieties, but without explicitly listing the typical variety, thus he did not list Aloe pumila L. var. pumila. Linnaeus’ Aloe pumila was subsequently effectively lectotypified by Burman f. (1701) [and later in enor by Scott (1978)] against the illustration in Commelin’s Horti medici Amstelodamensis, which is also the type of var. margarit!fera. This renders the name margaritifera homotypic with Aloe pumila L. (i.e. they share the same type). As the autonym (i.e. following automatically from the species name) for this species, pumila would normally have statutory priority over margarit(fera BUT, in the interim, the combination Haworthia pumila (Aiton) Haw. (1804) had been published, based on the name Aloe arachnoidea var. pumila Aiton, a quite different species that we know now as H herbacea. The publication of this combination renders Haworthia pumila (L.) Duval (1809) an illegitimate later homonym and thus not available for use in Haworthia. Because the combination Haworthia pumila cannot be used for Aloe pumila L. as a result of its prior usage for some other taxon it must be substituted with the next available valid and legitimate epithet, which is margaritifera. Note, however, that in any genus other than Haworthia the epithet pumila is the correct one to be used for this species.

The formal rendering of this situation is as follows:
Haworthia margaritifera (L.) Haw. (1819). Aloe pumila var. margaritifera L. (1753).  Aloe margaritifera (L.) Burm.f (1768).  Aloe pumila L. (1753). H pumila (L.) Duval. (1809), hom. illegit. non H pumila (Ait.) Haw. (1804). Lectotype, effectively designated by Burman f. in Prodromus florae Capensis: 10 (1768) [Superfluous lecotypification by Scott (1985)]: Illustration in Commelin, Horti medici Amstelodamensis, Pars altent: t.l 0 (1701): Aloe Afric: folio in summitate triangulari margaritifera, flore subviridi.

2. International Code of Nomenclature for algae, fungi, and plants (Melbourne Code)

3. Aloe pumila, Haworthia pumila; what or who is confused?  ISBN: 0-9534004-4-1 Bruce Bayer. Alsterworthia International Special Issue No.3. http://haworthiaupdates.org/aloe-pumila-haworthia-pumila-what-or-who-is-confused/
alsterworthia_special_3

 

4. Commelin, Johannes, Horti medici amstelodamensis rariorum tam Orientalis, vol. 2: t. 10 (1701)
http://plantillustrations.org/illustration.php?id_illustration=122192
Commelin t10 1701 H. pumila

 

 

5. Commelin, Johannes, Horti medici amstelodamensis rariorum tam Orientalis, vol. 2: t. 11 (1701)
http://plantillustrations.org/illustration.php?id_illustration=122193&height=750
Commelin t11 1701 H. pumila

 

6. Curtis’s Botanical Magazine, vol. 33: t. 1360 (1811) [S.T. Edwards]
http://plantillustrations.org/illustration.php?id_illustration=8348
ST Edward 1811 Curtis Bot Mag v33 t.13608348

 

7. Moninckx, J., Moninckx atlas, vol. 3: t. 12 (1682-1709)
http://dpc.uba.uva.nl/cgi/i/image/image-idx?c=botanie;view=entry;cc=botanie;entryid=x-421058064 and
http://plantillustrations.org/illustration.php?id_illustration=133655
Moninckx

 

8. History of Succulent Plants,  Bradley, Richard (t30) (1716)
http://www.botanicus.org/page/614136
Bradley t30

 

10. History of Succulent Plants,  Bradley, Richard (t21) (1716)
http://www.botanicus.org/page/614116
Bradley t21

Just what do we do with names for Haworthia?

Previously published in BCSJl (Cactus World) 30.4:211(2012)
M B Bayer

Taxonomy always provokes differing views, and Haworthia in particular has been subject to years of vacillation.  The author has long been a campaigner against the haphazard proliferation of new names for every new, morphologically different population or variant.  He questions the vagueness of a conventional species concept and pleads for a more reason-based, logical and sensible, communal approach to understanding and classifying Haworthia species.  He hopes in this article to convey a message which is relevant to whatever genera of plants you grow.  Photography by the author.

In Haworthia, professional botanists have struggled with and avoided the group because it is so infused with amateurs whose interest in the genus far outweighs any knowledge of botany.  So classification of Haworthia has muddled on with scant regard for the discipline of botany as a science.  Whether that has changed, is not for me to say.  I have personally been gathering information on distribution and variation for over 50 years and have very seriously tried to keep that in the context of the science I was trained in and present it in a manner that botanists can follow and hopefully accept.

What has developed is that academic and professional botanists have been working with the tools of molecular biology and the results of five independent studies have all pointed towards the same conclusion, which is that the species of Haworthia are elusive, and the related genera are also not adequately distinguishable in the DNA data.  The best solution they can offer is to merge the genera back into a single genus, namely Aloe.  My personal reaction is that this is not a new idea and also Gordon Rowley pointed this out as far back as the 1970’s.  I have also said that the subgenus Haworthia does not sit comfortably with the other two subgenera.  Had I been a true taxonomist I would have implemented that by separating Haworthia into three separate genera and that is what I really would like to see.  But the reality is that this does not solve the other problems that exist regarding Astroloba, Chortolirion, Poellnitzia, Chamaealoe, Leptaloe, Lomatophyllum, and the small Madagascan aloes.  True botany alone can resolve the current and a new classification (still in manuscript form) has been proposed by a group of scientists that will really ‘rock the boat’ as far as collectors are concerned.

In Haworthiad (2012:4), I wrote about Haworthia mirabilis ‘submagnifica’. (Ed. note: The name in inverted commas, according to the author’s system indicates a variant name rather than a formal conventional variety, subspecies or form.  It is his contention that there is no species definition and thus formal names have a large element of uncertainty.  Another option is to drop the use of any rank denotion at all).  It is one of the first populations linked to von Poellnitz’ H. magnifica long before so much was learned about distribution and variation.  I used the prefix “sub” because this means “somewhat”, “almost”, “slightly”, “partially”, and possibly a few other words that mean… it is, but it is not.  The population concerned is Komserante (Figs 1-2) and this particular population has acquired the name H. vernalis (Figs. 3-4).  But I think we need to start from scratch and drop all the ‘baggage’ of the years.  I personally have learned so much since I wrote my revision in 1996 that I know it is not possible to properly backtrack and retrace the passage forward by the use of Latin names.  Interfertility is the basis of the system we use to identify and describe species and my field experience was already proving that this cannot possibly apply in the way in which Haworthia has been, or is to be, classified.

Fig. 4 7778 H. mirabilis 'vernalis'. Komserante 4892 Fig. 3 7778 H. mirabilis 'vernalis'. Komserante 4891

It is quite evident that H. retusa and H. mirabilis, both of which I accept in a very much broader context, do hybridise and there are populations that fit between.  But first let me just explain that I regard H. retusa now to include H. turgida and all the variants of that species (nomenclatural priority obviated the use of the name turgida to cover the greater body of populations for this species).  In the same way I regard H. maraisii, H. magnifica, and H. heidelbergensis and whatever variants were attached to those, as H. mirabilis.  There are thus two species.  My further observation is that H. pygmaea and H. mutica are segregates from the common gene pool of H. retusa and H. mirabilis.  The Komserante population is the one in which that same gene pool is re-combining (Figs. 5-10).  I am not in the least sure of all the intricacies but it seems to me that it is actually the group of populations that I recognize as H. retusa var. nigra that is pivotal in the relationship of all these species that I recognize.  In this we discuss populations using names as prescribed by convention.  This convention caters for chronology and authorship and not for evolutionary pathways.  Both the names “retusa” and “turgida” precede the name “nigra”, but the populations that I now assign to H. retusa ‘nigra’ may better  fit the concept of evolutionary origin.

Fig. 5 7778 H. mirabilis 'vernalis' with a more velcro-like surface. Komserante 4897 Fig. 6 7778 H. mirabilis 'vernalis' resembling plants at Kruisriver. Komserante 4900
Fig. 7 7778 H. mirabilis 'vernalis'. Komserante 4901 Fig. 8 7778 H. mirabilis cf H. retusa, Komserante
Fig. 9 7778 possibly H. mirabilisXH. retusa. Komsernate Fig. 10 7778 possibly H. retusaXH. mirabilis, Komserante

The picture is complicated by the role of H. floribunda.  This also hybridizes with both H. mirabilis and H. retusa as odd hybrids as well as at a population level.  Just what are we to do?  History has demonstrated all too well that a bevy of ill-assorted interested parties trying to impose a botanical classification is going to produce nothing but conflict and confusion.   This has been going on now since the time that Smith, Von Poellnitz and Resende were simultaneously describing new species.  How are we going to turn around and arrive at the understanding and stability of names that we seek?

In the past I have been extremely reluctant to make the following suggestion, and even now am a bit hesitant.  What we need to do is turn to people who are employed to do this work.  Herbaria and herbarium botanists are tasked and entrusted to classify and name plants.  Perhaps it testifies to the complexity of the subject, or just its enormity, that these botanists have too often needed to defer to amateurs who have the interest, energy and enthusiasm and commitment to acquire field knowledge that a professional could never get the time or funds to do.  The unfortunate part is that sometimes amateurs may not be able to relate their knowledge adequately to academic botany.

So what is the solution?  It is that the community leaders assume the responsibility for the establishment of a system of classification that is meaningful to the community they serve.  (By community, I mean initially the botanists who should be providing us with scientifically sound classifications, then editors who are familiar with what botanists do, next are the Societies with their memberships, and also opinion formers in those groups. Finally included are the reviewers and commentators who lead opinion in one direction or another).  It is surely not that difficult to sit down together to discuss and arrive at a set of guidelines by which a decision can be reached as to what (not whose) system to accept.  A solution does not belong to anyone.  Latin names are assumed to refer to an entity called a “species”.  Botany has indeed been very lax and remiss in not providing a definition and this is the prime reason why amateurs have had so much freedom in generating Latin names for the most frivolous reasons.  Botanists themselves have often not been far behind.

I think it is time to change all this and must excuse myself from any decision making body or process because I have a vested interest in respect of all the words I have written on the subject. For further reading please visit http://haworthiaupdates.org

M B Bayer
PO Box 960
Kuilsriver 7579
South Africa

Email: bruce@shadowlands.co.za

 

Literature cited:

Bayer, M B(1999) Haworthia revisited. Umdaus Press, Hatfield.
-(2012) Plants in my collection 7: H. mirabilismagnifica’. Haworthiad 26(1): 4-5

 

 

 

Leaf arrangement in Aloe striatula

Herewith is an image of the leaf arrangement in Aloe striatula. I have numbered the leaves in inverse order to show that the leaves are as much distichious as trifarious i.e in two rows or three. The primary set is 1 through 10, the distichous set is 1, 3, 5, 7, 9 and 2, 4, 6, 8, 10. The trifarious set is 1, 4, 7, 10; 2, 5, 8 and 3, 6, 9. I have also added a picture of the leaf insertion – here it is entire and there is a leaf sheath around the stem – the actual point of insertion is at the pointer although the “veins” continue through that point to the stem itself. In this species the next leaf is inserted just below the opening of the previous sheath. Despite the leaves being alternate, they are spirally arranged. In Aloe broomii the leaf insertion is continuous and you can peel all the leaves off the stem in one piece. In most Haworthias the leaves are imbricate (overlapping alternately) but always in a spiral sequence. H. wittebergensis has leaves that have entire insertion and by memory the same is true for H. blackburniae and maybe for H. viscosa.

 

MBB7989 Haworthia pumila, Lemoenpoort

MBB7989 H. pumila, Lemoenpoort

Kobus drew my attention to a glabrous plant of H. pumila while he was photographing this species at Lemoenpoort. The plants here have a missing chromosome and tend to have a purplish colour. I have seen smooth non-tubercled leaves elsewhere. But do check out that one plant – if you look carefully you can see the leaves are in 8 nearly vertical tiers. Proper botanists recently, for Taxon, described the arrangement of leaves like this in only two tiers (e.g. H. truncata) as “distichous insertion”. This is weird. Are the leaves in this plant of H. pumila “octichous”? Is H. viscosa “tristichous”. No. The leaves in the aloids are alternately and spirally inserted.

7989.1 7989.2 7989.3 7989.4 7989.5 7989.6 7989.7 7989.8 7989.9 7989.10 7989.11 7989.12 7989.13 7989.14 7989.15 7989.16 7989.17 7989.18

 

 

Flower profiles

7989.1a 7989.2a 7989.3a 7989.4a 7989.5a 7989.6a 7989.7a 7989.8a 7989.9a 7989.10a 7989.11a 7989.12a 7989.13a 7989.14a 7989.15a 7989.16a 7989.17a 7989.18a 7989.19a

 

Flower faces

7989.1b 7989.2b 7989.3b 7989.4b 7989.5b 7989.6b 7989.7b 7989.8b 7989.9b 7989.10b 7989.11b 7989.12b 7989.13b 7989.14b 7989.16b 7989.17b 7989.18b 7989.19b 7989.15b

 

Haworthia minima and pumila flowers

6645.1b H. pumila

This flower (H. pumila) is apparently persistently regarded by botanists as actinomorphic (star-shaped, radially symmetrical) – as though zygomorphy (yoke shaped, bilateral, assymetrical) in the aloids is an uncommon condition!

Radial symmetry means the flower can be divided into 3 or more identical sectors which are related to each other by rotation about the centre of the flower. Typically, each sector might contain one tepal or one petal and one sepal and so on. It may or may not be possible to divide the flower into symmetrical halves by the same number of longitudinal planes passing through the axis. Zygomorthic flowers can be divided by only a single plane into two mirror-image halves, much like a yoke or a person’s face.

If you see the way the inner upper petal overlaps BOTH the two lower inner petals, you recognise that there can not be actinomorphy in aloid flowers.

 

 

Haworthia pumila
6645.1a H. pumila 6645.1b H. pumila H. pumila sn. 1a H. pumila sn. 1b H. pumila sn. 2a H. pumila sn. 2b H. pumila sn. 3a H. pumila sn. 3b

 

 

 

Haworthia minima
7519.1a H. min ima 7519.1b H. min ima H. minima sn1 1a H. minima sn1 1b H. minima sn1 2a H. minima sn1 2b H. minima sn2 1.a H. minima sn2 2a H. minima sn2 2b H. minima, Heuningrug 1a H. minima, Heuningrug 1b H. minima, Heuningrug 2a H. minima, Heuningrug 2b H. minima, Heuningrug 3a H. minima, Heuningrug 3b H. minima sn2 1.b

MBB6694 Kanetvlei, Hex River Valley as a variant of Haworthia nortieri.

MBB6694 Kanetvlei,  Hex River Valley as a variant of Haworthia nortieri.

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:

  1. MBB6694 Vreesniet, Kanetvlei.
  2. EA1441 Hex River Pass, east DeDoorns.
  3. 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 correctTo this I can add unexamined populations reported by PV Bruynsdeep in the Langeberg at Keerom Damand 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.

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Habitat

East of Swellendam, MBB7899 H. retusa ‘nigra’.

East of Swellendam.

Typical ‘pressure burst’ of white kaolinic soil from under more solid ferricrete where H. retusa and H. mirabilis are commonly found. East of Swellendam.

Southeast of Lemoenpoort looking up at locality of MBB7266.

View from Hammansberg eastwards, MBB7992.

View from Hammansberg eastwards, MBB7992.

Blinkberg, EvJ19550.

Die Nekkies. lookin west northwest.

Looking down the north face of Die Nekkies east to west. H. maculata.

Terrain south of Kunje, southeast of Citrusdal, MBB7597.

Blinkberg.

Blinkberg, EvJ19550 H. nortieri.

Southeast of Stoffelsrivier looking east to Sandhoogte.

Daphne and Bruce Bayer on the hunt, southeast of Stoffelsrivier.

Langvlei. The plants are in a tiny bit of rock just beyond the dumps.

View looking north from MBB7497 at Diepkloof, Stoffelsrivier.

Van Reenens Crest, MBB7955, looking east.

Habitat of MBB7496 at Diepkloof, Stoffelsrivier.

MBB7496 H. mirabilis Diepkloof Stoffelsrivier, view looking west to north of Kleinberg.

MBB7928 H. variegata, SSE Diepkloof, view looking east.

MBB7924 H. variegata SE Diepkloof, looking west to the Kleinberg.

MBB7921 Haworthia retusa ‘nigra’ at Van Reenens Crest.

Van Reenens Crest, locality MBB7915.

MBB7914 H. mirabilis, Van Reenens Crest.

White clay pressure burst.

Heuningklip, habitat of MBB7899 H. mirabilis.

Van Reenens Crest, 7958 View to 7957 arrowed,
Lawrence Loucka checking the GPS.

Van Reenens Crest, MBB7958, Daphne Bayer inspecting.

Niekerkshek looking south to the Potberg, MBB7963.

Klipbankskloof westward. MBB7953.

Klipbankskloof, Looking westward. Habitat of MBB7953.

MBB7954 Rondeheuwel, view looing northwest to Riviersonderend.

MBB7954 Rondeheuwel.

JDV92/64 Sanddrift, Drew.

Spitzkop, MBB7966.

Spitzkop, MBB7966.

Looking south west over Muiskraal to Garcia Pass

Looking west from north of Muiskraal.

Looking southwest to Garcia Pass.

Habitat H. floribunda. Plaatjieskop.

Habitat H. floribunda. Plaatjieskop.

Tanqua Karoo, Bantamsfontein

Tanqua Karoo, Bantamsfontein.

The Skeiding homestead.

The Skeiding homestead.

Looking from Swartrug towards Riversdale.

Looking from Swartrug towards Riversdale.

Looking from Morning Star to Kransrivermond.

Looking from Morning Star to Kransrivermond.

 

 

 

 

Comprehension and significance

My writing has been described in all kinds of terms, hermetic and pretentious being two of the adjectives used.  Recently Kris Tamayo also suggested that he had trouble understanding what I wrote or write.  The fact is that writing and expressing yourself is difficult.  But the first place is to be clear about what you want to say.  Or is that in fact the first place?

Writing is a means of communication and it really only should start when you are clear about what you think and what you want to say.  Then it requires that the listener is clear about what he/she wants to hear and has the common cultural heritage that permits communication and understanding to occur?

In writing and talking about plants I personally get very frustrated by the technical problems of definition and knowledge that mess up communication completely.  This is one of the obstacles in classification where there is no species definition and we do not actually know what species are.  There are a lot of other obstacles.  Recently someone wrote and implied that there were a lot of significant differences among Haworthia that could be used to arrive at a better classification (than any already available).  The point I would make is that this person has his own idiosyncratic view of what significance means.   This is not strange at all because a prominent scientist was once applying the statistical measure of standard deviation to two and three measured samples.  That measure probably cannot be used until many more measurements are made.   What is taken to be significant may be quite irrelevant to the actual question of whether there are more or less species.  This is why amateurs and collectors should keep clear of classification.  The professionals already have too many problems.

The characters we use to make identifications are important in that they may be of the yes and no kind i.e. present or absent, or they may be graded from vague to prominent.   So it is very easy to go to one end of the scale and take only the prominent or what happens to strike your eye.  This is exactly what happens.  Unless followers and interested parties realize the impact this sort of decision making affects what they may want to know and understand, there can never be any harmony and peace in the classification process.

Look at these flowers and see what you can glean from them…

 

These just happen to be the only three flowers I have of a few plants of Haworthia herbacea from recent sampling.  They are shown here in correct proportion to one another with the third being 18mm across at widest spread of the two upper outer petals.  So we have two things we can call characters i.e. size and colour that we could say in respect of this simple sample,  that they are significantly different.  No matter how many times or how we measured these two things, this fact would stay the same.  The plants happen to be from two populations and we can then ask if this is true for those populations.  I did ask such a question of both H. herbacea and H. reticulata, and ended up by learning that I needed a sample of about 200 flowers to arrive at a statistically true answer at a probability of 95%.  The thing is that I could go a little further south and sample another population and get a really pink flower with a spread of 25mm or more  that would nearly double the spread of my measurements.

There are several incidentals here.  One is the delineation of the mouth into the tube of the flower.  Why is it so clear in the third picture?  The second is that the first flower has not opened as flat across the face as the other two despite being at the same expected state in respect of time from opening.  The third is that the name “subregularis” was used in this genre of flowers because the petals are so equally spread; perhaps less-so in the middle picture.  Still a fourth curiosity is that in the southwestern species with the more extreme biarcuate bud with the fish-tail tip, is how the tips of the upper outer petals are “replicate” – i.e. the margins tend to fold together.  In the Worcester/Robertson Karoo particularly H. herbacea and H. reticulata have the “regular” flower shape.  But in H. mirabilis in this area, the upper outer petals may be held in a plane directly behind the inner outer petal and do not spread at all.  There the bud tip is still fish-tail and the upper outer petal tips very replicate.

 

 

Haworthia mutica (groenewaldii) and its twisted leaves.

In this article Bruce Bayer responds to the notion that apparent leaf twist arrangement is a defining characteristic and further explains his disagreement in recognizing the Buffeljags plants as a new species.  (Also see Haworthia flowers – some comments as a character source, Volume 7, Chapter 4:- What is typical Haworthia mutica?, and Volume 7, Chapter 2:- Further exploration in Haworthia. Further to finale.)  The species definition Bayer uses is that populations are fractal and DNA is governed by mathematical non-linearity.  What does that mean???   We have space with two dimensions latitude and longitude, and we have time with two dimensions – calendar time, and the speed (instability) of the arrangement of the DNA base pairs.  At any moment in linear calendar time there will be an arrangement of the DNA depending on the stability of the DNA.  At one time there will be a clear set of ‘species’ and at another time a different set.  If very unstable there is no grouping at all.   It should be understood that botanists do not use the rank of variety anymore (should not), and subspecies is correct, and that botanical “variety” is not the same thing as a variant.  – Lawrence Loucka

 

Haworthia mutica (groenewaldii) and its twisted leaves.
By M.B. Bayer

There is some argument about the status of this population of plants at Buffeljags.  I have explained my opinion of it based on a species definition that I use.  I also have reported on three other populations a short way away at Rotterdam.  Furthermore I have discussed the flowers at length in a flower report.  These are all available free on Haworthiaupdates.org.  Gerhard Marx does not agree.  The disagreement first has its roots in what constitutes a species and Marx stays with the standard view that characters are what define species.  I opt for the view that species are systems related to geographic distribution and to all the elements that drive vegetation and change (evolution + equals change from some unknown initial condition).  I think these patterns of change and difference are fractal i.e. detailed pattern repeating itself.  Perhaps it would be more correct to say that the organization of pattern is according to a mathematical function which is non-linear.  This means that the end product has many different outcomes.  But this is complexity just of argument that none of us can deal with.

What comes into the geographic nature of species is also the nature of habitat.  What happens is that we have a set of apparent species in Haworthia with a known distribution range.  These species are primarily H. retusa and H. mirabilis.  There is clear evidence that H. pygmaea  and H. mutica emerge from a milieu of populations of those two and that H. floribunda is also involvedBuffeljags is geographically central to this arrangement and the habitat (wrongly described in the description of H. groenewaldii) is very unlike those where the named species generally occur.  It is thus no surprise that the plants appear different.  The Buffeljags population and its habitat also differ to a small degree from the west side of the river, but both are essentially geologically fairly recent river alluvial deposit.

Marx is insistent that the plants at Buffeljags are so different as to be a discrete species and I disagree.  My disagreement is based on my experience of characters in plants.  In Haworthia I think these are few and obscure.  Thus it is almost impossible to delineate or circumscribe a species by characters and no one has succeeded in producing an identification key that can work.  All the differences of opinion and argumentation about names come down to this issue of a species definition and the characters available to recognize them.

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Genetic history – the place in Haworthia classification.

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

 

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 travelled 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.

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Addendum Haworthia pubescens MBB8011, SW Sandberg

Addendum.  H. pubescens MBB8011, SW Sandberg.

I need to point out that there is a still earlier article which covers Haworthia maculata (Haworthia maculata <–> Haworthia pubescens) that lays the basis for this discussion.  In that article I note the position of the Sandberg to Cilmor and DeWetsberg and intended to include the Sandberg H. pubescens in that article.  We could not get landowner contact and so that fell away.  However, this problem was overcome and we first explored a Dwyka Tillite outcrop southeast of Sandberg.  There is a vast accumulation of windblown sand on the first hill and we saw no Haworthia.  There is a smaller hill further to the southeast that is also Dwyka and erosion exceeds wind deposition so smaller non-geophytes do quite well.  We found both H. herbacea (see fig.1 MBB8014) and  H. pumila there.  From there we went to the southernmost point of the Sandberg.  A misjudgement landed our vehicle in mud and the drama to get out limited the time we had to explore.   We found a lone H. herbacea (fig. 2 MBB8012).  Returning a week later we approached the Sandberg from the southwest, and almost immediately on reaching the top we found H. pubescent.  Fig. 3 is a view towards Cilmor and DeWetsberg where the plants appear to be intermediate H. pubescens↔H. maculata.  The picture is useful to get some idea of the role of geographic and geological considerations.  The high mountains in the background are Table Mountain Sandstone and no Haworthia is known there.  I am not certain that this is true and G J Payne did tell me that he had seen plants on the extreme lower right and south of the Brandvlei Dam.  But also on the absolute distant and absolute left, is the Riviersonderend Mt.  That is also TMS.  The deep Wolfkloof Valley behind that is the locality for the much unexpected H. herbacea ‘lupula’.  (These inverted single commas are not entirely necessary but I use them to underscore my informal use of names that have less reality.  The var. lupula is real).  The mountains ahead of that last line are Hammansberg on the left and the Moddergat to the right.  Between there and DeWetsberg has not so far turned up Haworthia, but this is an exploration problem.  Behind the DeWetsberg is also underexplored.  H. herbacea does occur between DeWetsberg and behind the mountains on the low right just in the picture and also east of the brickfield out further right.  H. maculata is only known in this area along the Nekkies north (further to the right) of the Brandvlei Dam just visible in the picture.

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Haworthia maculata ↔ Haworthia pubescens, MBB8002 Cilmor.

In Haworthia Update Vol 9 there is a report of a population MBB7997 identified as Haworthia pubescens from north of the Cilmor wine cellary.  This is approximately 2-3km southwest of the type locality for the species.  I noted that the plants have less spinuliferous leaf surfaces and there is a degree of surface translucens and maculation (spotting).  I also presented 3 pictures of MBB7271 of what I identified as H. maculata from south of the Cilmor cellar.  When I first visited this locality I had no problem identifying the few plants I saw as H. maculata on account of their marked spotting.  However, on a recent visit we struggled to find plants at all and the few plants we found were too embedded in rock cracks to make any worthwhile identification.  So we revisited the site to explore more extensively and located a large number of plants higher up and slightly west of our first sightings.  These plants are illustrated here.  They incline more to H. maculata than the plants at MB7997 and I have accessioned the population as MBB8002.  There is the usual expected large variation in respect of superficial and observable characters.  The plants can be proliferous and cluster, more so than at MBB7997.  Similarly the leaves can have more translucens and even less spinuliferousness of the surfaces.  Some plants have few and quite thick swollen leaves while others may have more and very slender pointed leaves.  I have not observed the flowers and really do not expect them to make any difference to the problematic classification of populations that again are neither here nor there in a narrow concept of species.  H. herbacea occurs at all four geographic positons at a radius of about 2km.  At the brickfield to the northwest as well as just northeast of the Brandvlei Dam wall it is evident to me that there is a transition between H. maculata and H. herbacea.  I did report the known distribution of H. maculata in Update 9.  While there is no suitable habitat between Die Nekkies hills at the Brandvlei Dam and the Audensburg or Kanetvlei, there is unexplored suitable habitat southwards to Moddergat and Hammansberg.  There is no evidence of H. maculata eastwards to where H. reticulata is known about 15km east on Ribbokkop.  Westwards no Haworthia is known although G.J. Payne did inform me that he had observed plants in the hills immediately southwest of the Dam at the now submerged hot spring in the Brandvlei prison area.

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Comments on H. marxii

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.

Righting some misconceptions.

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.

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New finds in Haworthia.

Previously published Cact. Succ. J. (Los Angeles) 84(1): 41-50

Map - east of Swellendam

 

Map Legend – east of Swellendam.
1. JDV84/75 Haworthia retusa ‘turgida’.
2. MBB6666 H. retusa ‘nigra’↔ H. mirabilis.
3. MBB7898 H. retusa ‘nigra’.
4. MBB7899 H. retusa ‘nigra’.
5. MBB7897 H. retusa ‘nigra’.
6. MBB7896 H. retusa ‘nigra’.
7. MBB7871 H. mirabilis.
8. MBB7823 H. mirabilis.
9. MBB7909 H. mirabilis
10. MBB7805 H. mirabilis.
11. MBB7801 H. mutica ‘groenewaldii’.
12. MBB7886-7889 H. mutica ‘groenewaldii’, H. mirabilis, H. minima, H. marginata.
13. MBB7722 H. floribunda ‘major’

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The reality of Drosanthemum micans L.

Donald A. Levin (2000) quotes Raven, Berlin and Breedlove (1971), who wrote…“our system of names appears to achieve a reality which it does not in fact possess”.  I find this a curious quote, as Levin was discussing species concepts and we could ask if species themselves have any reality.  There is a lack of a universal definition for the word “species” and I find the recurring reference to “concept” as related to the word, very confusing.  Why should the species be a concept, subject to individual interpretation?  This is of course if they have no reality and we each create our own.  How useful is this for science?  Donald goes on to generate his own “species concept” in which he proposes…“that each species has a unique way of living in and relating to the environment and has a unique genetic system…”, and he refers to this as the eco-genetic species concept. (But still we do not know what he means by “species”.)   He says that the ecological properties of such species are not uniform within the species and thus not equivalent to the taxonomic properties of species, “which are chosen because they are conservative and stable attributes”.  It would be interesting to know just what he means by “taxonomic properties” and I presume he means primarily morphological characters.  Certainly there must be taxonomists who utilized or have utilized ecological facets to decide on their species.  It must also be recognized that the taxonomist is confined to the material at his disposal for examination and decision making.

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Very brief note re Haworthia nortieri flowers.

Some criticism about my supposedly having ignored the flowers in Haworthia comes at a very inopportune time. I set aside flowers for the reasons very obvious from the historical record but also because of the considerable problems of similarity in the appearance of the flowers in apparently quite different species. My priority was a geographic overview and a rational basis on which discussion and decision making could be based. It I just grossly unfortunate that other writers and critics seem to be wedded to a classification paradigm locked into the approach that prevailed 70 years and more ago. This in the total absence of a species definition other than the vague acceptance of a zoological one based on interbreeding capabilities. This ignoring the ease of hybridization among Haworthia variants in general.

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Haworthia marxii and H. truteriorum in relation to rational classification.

(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.

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Aloe pumila, Haworthia pumila; what or who is confused?

With some astonishment I learned recently of an opinion that the name pumila as used in Haworthia is confused and therefore should be discarded.  There is no doubt that it is difficult to unravel the literature and the usages of the name, but I think there are a number of important questions which should first be answered.  Is the name confused or is it us and others, as individuals, who are confused?  It is worth asking such questions because names are words in the process of communication and mutual understanding around which all knowledge and its sharing revolves.

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