Volume 3, Chapter 2:- Flowers of some Haworthia

Posted on November 27, 2011 by Bruce Bayer

I have several times been rather taken aback when botanists have been among those who have derided the fact that I have not apparently looked to flowers as a source of characters for identification of Haworthia species. Others have intimated that there are diagnostic characters in the seeds and even in the capsule structure. The essence of this kind of complaint is that there are these definable units called ‘species’ and that there is some linear and dichotomous set of characters by which they can be separated. The perception remains alive for the technology of surface structure, pollen sculpturing, DNA and molecular structure, and expectations which flow from and for these real and presumed character sources.

My opinion is that these techniques or methodologies will not tell us much more for Haworthia than what can be deduced by common-sense scrutiny of the plants. They may be extremely exciting and enlightening in view of broader relationships and theories of origin and migration even of vegetation. But their value to the collector and grower will always be minimal.

Here I want to picture some flowers of the subgenus Haworthia and show that while there is indeed ‘character’, the magnitude and ranges are such that they cannot be of any assistance for separating those elements that can be practically recognised as ‘species’. It is more probable that it will rather fuel the argument for less species. In the subgenus Hexangulares, my observation has been that while the species are vegetatively readily distinguishable and in most cases, geographically quite discrete, the flowers are indistinguishable. Within‑species differences may exceed the differences between the flowers of different species. In the case of subgenus Haworthia, it can be observed that in the one case where the flower is really notably different i.e. H. nortieri var. globosiflora (including H. pehlemanniae) there is a gradation to the normal flower of H. nortieri var. nortieri. Thus, within species difference may exceed that between species.

The flowers of H. herbacea and H. reticulata are interesting because they are quite large and the tip of the flower bud is ‘fish-tailed’. The tips of the upper outer petals are pinched together. But this character is present in the whole of the southern Cape complex of about nine species and extends to Little Karoo species as well.

Fig. 1. Left. H. maculata, Audensburg, N. Worcester, MBB6815. Centre. H. nortieri var.nortieri, Sneeuberg, Koue Bokkeveld, MBB 6158. Right. H. maculata, Audensburg. N. Worcester, MBB6815.

Here are H. maculata and H. nortieri var. nortieri – the former from the Audensburg north of Worcester, and the latter from the Sneeuberg in the Koue Bokkeveld north of Ceres. The plants are generally very similar and the argument to maintain species identity is no more substantial or tenuous than for any others of the subgenus. The flowers generally are different. H. maculata has the fish-tailed bud of H. herbacea and H. reticulata. This is evident in the illustration. The impact on the open petals is quite marked in that the upper outer petals tend to have pinched ends and the flower appears a little more regular i.e. the petals are equally spaced on radii from a point centred on the mouth of the tube. Colour is notable in this case because most of the Audensberg H. maculata flowers are notable pinkish. In the H. nortieri illustrated here they are white (ignoring the usual darker colour of the mid-vein). But I have photographed the one plant of H. maculata in which the colour is also white and the flowers less regular. It is almost impossible to separate this flower from that of the H. nortieri illustrated. This observation is also restricted to these particular specimens. It is well known that H. nortieri flowers can be very colourful with a notable yellow tube (yellowish-green, golden yellow and canary yellow fide G.G. Smith 1950).

The pinched bud does not always produce a more regular flower, and in H. maraisii, H. magnifica and H. mirabilis quite the opposite may occur with the upper outer petals almost overlapping behind the inner upper petal.

It has become increasingly evident to me that the separation of H. arachnoidea and H. mucronata as two independent systems, and therefore species, is difficult. Therefore I illustrate five specimens from four populations in:

Fig.2. Left – H. arachnoidea var. nigricans, between Barrydale and Montagu, MBB6868. 2scd Left – H. arachnoidea var. setata, Prinspoort, NE Montagu, JDV92/93. 3rd Left – H. arachnoidea var. arachnoidea, Robertson. 4th-5th – H. arachnoidea var. arachnoidea!, DeDoorns.

The spike on the left is of a doubtful population of H. arachnoidea. The plants are spinose as H. arachnoidea is supposed to be, but generally less than is expected in that species, and its location between Barrydale and Montagu makes it suspect. The second spike is that of unmistakeable H. arachnoidea var. setata from Prinspoort where the variety nigricans and H. mucronata var. inconfluens are also in proximity. The third spike is that of H. arachnoidea var. arachnoidea from west of Robertson. The fourth and fifth are of a collection from near De Doorns in the Hex River Valley. There are four plants in the collection and they have translucent spots on the leaf rather similar to H. marumiana var. dimorpha. The inflorescences are quite lax and as these two shown occupy a place in the greenhouse alongside the Robertson H. arachnoidea, it is obvious that the sparse lax spike is not light influenced. The flowers are sparsely spaced on this lax spike and the tube and flower colour is notable greenish. There does not seem to be any notable consistency in these differences and in many collections this kind of difference appears. The plants and flowers obfuscate the separation of H. arachnoidea and H. marumiana. The problem also arises as to how to name it. It is not typically H. arachnoidea var. arachnoidea as the nomenclatural system requires, and neither is it any of the other named variants.

Fig.3. Left – H. mucronata var. inconfluens!, west of Montagu. JDV97/56, MBB6690. 2scd Left – do. 3rd Left – H. mucronata var. inconfluens!, north of Montagu. JDV96/56, MBB6689. 4th Left – H. arachnoidea var. nigricans!, Schoemanspoort north of Montagu. JDV92/43. 5th Left – H. mucronata var. inconfluens, Touwsberg, JDV97/149.

The two left spikes are of an H. arachnoidea/H. mucronata intermediate from near Montagu. The flowers are more compressed together on one spike than on the other. The collection is notable for the intense yellow colour in the tube. The third spike is from the same geographic continuum also near Montagu but slightly eastward, inclining more to H. mucronata; as do the collections and next two spikes from Schoemanspoort near Oudtshoorn and the Touwsberg north-east of Montagu. The collections are probably of the variety H. mucronata var. mucronata. But I have explained elsewhere that H. arachnoidea var. nigricans is a buffer to absorb these problem elements which are neither one species nor the other, and not constituting any geographically cohesive entity. Incidental is that the third spike’s origin is in JDV97/56, a collection which also has the number MBB6689 and which contains individuals which could be H. arachnoidea var. nigricans, H. mucronata var. mucronata, H. mucronata var. rycroftiana, or none of these! This helps explain why I object so to opinions which are based on the unrecognised contention that one specimen can represent a population, a variety or a species. It also shows that it is better to work with a single accession system and one collector’s number rather than generate a series of personal numbers.

Fig.4. Left – H. arachnoidea var. nigricans, between Barrydale and Montagu, MBB6882. 2scd Left – do. 3rd Left – H. decipiens var. pringlei, Waterford, Jansenville, MBB6855. 4th Left – H. arachnoidea var. scabrispina, SW Laingsburg, MBB6486. 5th Left – H. decipiens var. pringlei, SE Mt Stewart, MBB6582. 6th Left – H. cooperi var. gordoniana, N Jeffrey’s Bay, JDV96/92.

Is a montage of two spikes on the left of H. arachnoidea var. nigricans from between Barrydale and Montagu. Then there is a spike from a plant from Waterford near Jansenville (my new H. decipiens var. virella). The plants are on the broad interface of that variety with H. decipiens var. xiphiophylla and they are not typical of anything. The next two spikes are from plants of H. arachnoidea var. scabrispina from south-west of Laingsburg. The differences are self-evident viz. a densely compacted raceme and a sparsely flowered one. Colour also differs. The sixth and seventh spikes are of H. decipiens var. pringlei from Mt Stewart and of H. cooperi var. gordoniana from north of Jeffrey’s Bay (this latter is actually close to H. cooperi var. picturata). The differences across the figure are actually minuscule and when one has to compare several spikes from each collection these differences become quite untrackable.

Fig.5. Left – H. cymbiformis var. cymbiformis! Kaboega, Zuurberg, MBB6903. 2scd Left – H. decipiens var. decipiens, S Aberdeen, GM547. 3rd Left – do. 4th Left – H. cymbiformis var. incurvula, Pluto’s Vale, MBB6884. 5th Left – H. cooperi var. viridis, Perdepoort, Sapkamma, MBB6858. 6th Left – H. cooperi var. isabellae, Holriver, Patensie, PVB7128. 7th Left – H. cooperi var. isabellae, Milton, Hankey, MBB6801.

Consists of a specimen which on vegetative grounds is unquestionably H. cymbiformis (but which variety is it? a la H. arachnoidea above). In the context of its near neighbours on the Zuurberg, and their similarities, it is actually continuous with H. cooperi. The plant (and others in the population) is very bright green yet in every other vegetative aspect is typically cymbiformis. The inflorescence is a bit sparse while the flowers are less white and perhaps sturdier than any norm which can be stated for that species. However, this inflorescence and flowers do not enable any better differentiation of the series of populations which link H. cooperi, several of its varieties, and also H. aristata in that area. The second and third spikes are from a collection of H. decipiens var. decipiens from south of Aberdeen. They are very different from each other. The fourth spike is of H. cymbiformis var. incurvula from Pluto’s Vale (and I have found it possible to make a perfect match of such a flower with the very improbable H. pulchella var. globifera, which is patently from another system). The fifth spike is from H. cooperi var. viridis and the last two are of H. cooperi var. isabellae from Holriver, south of Patensie and Milton south-west of Hankey.

Fig.6. Left – H. bolusii var. blackbeardiana (batteniae of Scott), Josefsdal, Cradock, JDV91/102. 2scd Left – H. decipiens var. decipiens, E Willowmore, MBB in KG140/72. 3rd Left – H. decipiens var. decipiens, Springbokvlakte, JDV94/85. 4th Left – H. cooperi var. gordoniana to H. decipiens, Georgida, Uniondale, MBB6937. 5th Left – H. decipiens var. decipiens, Steytlerville, PD2153.

Lastly Figure 6. These are flowers of H. bolusii var. blackbeardiana from Cradock, H. decipiens var. decipiens from east of Willowmore (note the many florets per bract), and H. decipiens var. decipiens from Springbokvlakte. The fourth spike is of H. cooperi var. gordoniana where it intergrades to H. decipiens at Willowmore and Uniondale. The last is another also of H. decipiens var. decipiens from the Springbokvlakte.

If any one species complex (as I have identified and recognised them) is taken, the same problem of variation arises. The variation in the flowers is of the same degree and intensity perceivable in the size, leaf arrangement, number, colour, texture, spination and armature of the rosette and leaves.

The conclusion I would like to make is that it is not possible to generate a classification system on any other logic than that I have used viz. geographic arrangement and broad vegetative similarity. It is possible to generate a diagrammatic model to show a cladistic (branching) structure and model for species. But this will have to have three axes – two for geographic space, and one for time. This is realistic, and far more so than the pressure that is exerted to produce the artificial two-dimensional cladograms botanists seem to favour and which the nomenclatural system caters for. ♦

Volume 3, Chapter 13:- Haworthia IS confusing

Posted on December 4, 2011 by Bruce Bayer

In a very interesting book by Stephen Gould entitled “Rock of Ages”, in which he propounds his principle of NOMA – non-overlapping magisteria. This states that science and religion should not be confused nor mixed.

So this is not a confession of confusion – you do not confess to what is obvious. It is an admission, and an admission can be construed as an apology. But, as a rhetorical question, how can one apologize and expect forgiveness when one continues to walk the errant path?

I started to write about Haworthia to dispel confusion, and yet more than 40 years on, this confusion has not become any less. The conclusion I have come to (and I wish it was a closure) is that the prime source of confusion is simply the human condition. In mystic philosophy one can read… “Born in ignorance, we live in ignorance and we die in ignorance.”

I think that my interest in Haworthia stems from my conscious effort to dispel this primal confusion and find some of the order in my view of creation. The classification of plants suggested just one small piece of my world which was available to me, and Haworthia as one group which no one else could explain to me. What have I now learned and what contribution does this make to dispel confusion?

My courage to now say something more directly arises from a recent request by SANBI to write a synopsis of Haworthia for an E. Cape Flora. I feel that I have done that fairly successfully. The problem is now to produce a similar product for the SW Cape and this is considerably more difficult.

To explain Haworthia one has to first cross the hurdle of the present classification of the Asphodelaceae and the perceptions that Aloe, Haworthia and other genera are clear discrete groups that the classification suggests. Ignore completely the issue of whether the so-called species are clearly separable. Haworthia consists of three quite discrete groups which have no closer relation to each other than do any other of the extant Asphodeloid genera. They each have their own problems and idiosyncrasies but it is the subgenus Haworthia which concerns me most.

In 1975 I prepared a map to illustrate the relationship of the SW Cape species (primarily south of the Langeberg Mts.) and this was published in Excelsa (5, 1975). In this map I tried to illustrate the problem of continuity which simply makes it impossible to recognize clear closed groups of plants which we can with any truthfulness say are species. It is the reality for Haworthia, and my conviction is that the model which underlies the Latin binomial system is fundamentally flawed. It works because our ignorance clouds its shortcomings.

Map 1 Distribution of SW Cape species of Haworthia

Updating my map may show why (Map.1). It is perhaps possible to identify three main elements that are nevertheless extremely difficult to map. Very seldom do we find all three growing in close proximity and never do we find any of the components I suggest doing so either. We often struggle to suggest which of the three we are being faced with.

The names we can use for these three are:-

H. retusa – to include or cover mutica, turgida and pygmaea

H. mirabilis – to include or cover maraisii, magnifica, emelyae and heidelbergensis

H. floribunda – to include or cover parksiana, chloracantha, floribunda and variegata.

There are other elements viz:-

H. herbacea – to include or cover reticulata, maculata and pubescens

H. rossouwii –

But this is a simplification and not a solution.

What simply has to be recognized as a fact of life that this problem is not of my creation and I do not believe that the use of any technical sophistry, trick of classification or nomenclature will possibly dispel it. These “species” are as interconnected as the strands of a complex web as intricate as any a confused spider could construct.

Essentially one has a mid- to late-summer flowering group and a spring flowering group, but they are linked. H. pygmaea, in the retusa complex, actually springs from the mirabilis complex; while its counterpart mutica in the west, seems to spring from the retusa complex. Emelyae, in the mirabilis complex, seems to be linked back to rossouwii via multifolia. These are the kinds of realities one has to deal with.

The relationship of the three main elements I have mentioned differs from point to point on the map, and to describe these relationships means that one has to virtually deal with populations and groups of populations one-by-one. I have done that, particularly in the book Haworthia Update Vol. 1n and again in Vol. 2. But since the drafting of the last manuscript, I have been to the field again and found more material, which I will show now.

Essentially there are three areas which I will cover:- a. the southern Potberg and where the Breede River enters the sea south of Swellendam (Map 2); b. secondly Klipfontein at the northwest of the Potberg (Map 3); c. thirdly an area just west of that which I also call Die Kop, Wydgelee (Map 4). The localities are not indicated precisely on these maps but the detail is in archived and available information.

Results:

a. The southern Potberg.

Two of three relevant populations are discussed in Chapter 15. These are ADH594 Sandhoogte, and MBB7248 Lower Breede River H. mirabilis (pilosa). I refer to CB2018 and I can now report and illustrate it myself. This is MBB7251 (Figs 2a & b) from Buffelsfontein within the DeHoop Nature reserve. In the field the plants are not distinguishable from ADH 594 and grow in exactly the same Fynbos habitat viz a very rocky and grassy streamside slope with a dry northern aspect. The illustrations are of plants cultivated and hence far greener and softer than in habitat. What is striking is the tendency to surface spination which is such a feature of MBB7248.

b. Northwestern Potberg.

Some of these populations are also covered in Chapter 15. These are MBB6890, MBB6886, MBB6882, MBB6889 and MBB6544 (figs A18…22). My comment that H. variegata occurs here too should be borne in mind. This is on the upper slopes of the extreme western end of the Potberg. There is another record of C Burger’s from further east and south of Diepkloof for which I coined the name H. variegata var hemicrypta. Some doubt will now be thrown on the wisdom of that decision. The mirabilis populations referred to above are on the farm Juliesfontein and my new records are now east of that towards Diepkloof along the Breede River.

1. MBB7487 H. floridunda. Byeneskop (figs 3a to g). No good opinion is ventured in Chapter 15 concerning the populations noted above. Those populations seem to fall in the context of an interaction between H. maraisii/heidelbergensis/floribunda and I warn of infusion of H. variegata. The Byeneskop is on the very eastern border of the farm Juliesfontein and the plants are surprisingly and confidently comparable with the typical form of H. floribunda. The leaves are generally fairly strap like and flattened to the characteristic twisted ends as evidenced in floribunda. A few plants (see fig.3f) do have shorter and stubbier suberect leaves which characterize so many collections that confound the recognition of the relevant species. This particular habitat can be described as Renosterveld on silcrete with dominance of white clay and much grass and other succulents. Similar plants were also seen about a kilometer eastwards on the verge of vegetation transitional to Fynbos.

2. MBB7492 Klipfontein East (figs 4a to d). This is again a typically H. floribunda-like population. Whereas the preceding tends to be slightly tuberculate with the rougher greyer texture and colour of H. maraisii which would suggest floribunda var dentata, these plants tend to have a smoother leaf surface. Pictures of the flower are included although of very little diagnostic significance. The habitat is a steep rocky sandstone hillside vegetated with low Fynbos species.

3. MBB7494 Klipfontein East (figs 5a to d). The plants suggest H. floribunda except that the colour of the leaves is greener and there is a tendency to translucence, or less opacity of the leaves. The white flecks in the leaves are quite conspicuous and are more often encountered in H. turgida. Their significance taxonomically is probably nil as these markings/inclusions may appear in plants as remote as H. angustifolia var baylissii on the Zuurberg, E. Cape. The habitat is again short grassy Fynbos but unusual because of the presence of finely textured white quartz rock.

4. MBB7495 Klipfontein East (figs 6a to c). While we have been looking at plants on a series of buttresses of the Potberg, these plants are now closely associated with large white quartz boulders. They are small and although very similar to the preceding, the leaves seem to have lost the characteristic rounded ends and the margins are relatively strongly toothed.

5. MBB7496 Kleinberg (figs.7a to g). This population is only about 1km east of the preceding but there is a transition to Renosterveld. The habitat is again silcretious with the typical white clay substrate. This seems to be a very erodable surface and plant cover is quite low. The plants are surprising because they depart quite radically from the floribunda-like mode of the preceding populations. They are now distinctly magnifica-like and particularly reminiscent of var atrofusca except much smaller. Curiously a population across a small valley southwards in sandstone and Fynbos is in keeping with the floribunda-like finds westwards.

6. MBB7499 Juliesfontein (figs 8a & b). We returned to Juliesfontein to look at a promising rocky slope between Byeneskop and our previous closest collection on Juliesfontein. These are almost directly north of H. variegata and as can be seen from the pictures they revert to the forms described in Chapter 15 for that area viz. there is a similarity to heidelbergensis. The more leaves are more frequently pointed rather than rounded and translucence and venation is more conspicuous.

c. Die Kop, Wydgelee.

The nearest plants dealt with in other chapters are MBB7539 at Tarentaal that I liken to magnifica var atrofusca and MBB6030 at Napky which is maraisoid with floribunda-like character (type locality for H. maraisii var simplicior with rotate leaf-tips). It is important to note that the Tarentaal plants are not uniformly larger that my identification suggests and also that H. mutica is also present at its most southeasterly locality known south of Napky. Tarentaal only just appears on the map and the mutica locality is just off the map to the upper right (northeast) corner. It should be noted that populations assigned to H. heidelbergensis occur to the west at Kathoek, Beyersdal, N. Windheuwel and terminating in the contentious var minor at Rooivlei north of Bredasdorp. I think if an overview was now made of all these populations I have assigned to heidelbergensis in different chapters and in different publications, it will have to be concluded that it may represent the pivotal element in the whole classification process. Where it was the least represented species in the period preceding publication of Haworthia Revisited it is now far better known and any hypothesis prepared to test relationships in these southwestern Cape species Haworthia will need to question this centrality. Die Kop is a set of 5-6 silcrete and ferricrete hilltops of varying size and height but otherwise not significantly different from a large number of such habitats extending from Stormsvlei in the northwest and terminating against the Potberg and Breede River in the southeast. Collections from several of these have already been reported on in Chapter 15 with the general observation that their identification is in the uncertain linking maraisii and mirabilis. I hope, in the minds of readers, that I have not excluded heidelbergensis from this milieu.

1. MBB7500 Die Kop East (figs 9a to v). I doubt if any collection has generated such reservations in my mind as this one has and many illustrations are used to express the problem. The plants are large and up to 80-100mm in diameter. They are closely spaced in a small grassy, non-rocky area which seems to be geomorphically stable. They are extremely variable and resemblances extend from badia to retusa to mutica. The leaves may be short and rounded or fairly long and attenuate, closely adpressed to the ground (recurved) or sub-erect. One notable feature is that the plants have a milky colouration to the leaves that Seven Hammer once remarked on as a feature of H. mutica. While variability is known to be great, it is seldom that it is as dramatic as this in a population of plants as they occur in the field.

2. MBB7502 Die Kop West (figs 10a to c). The plants here are smaller and more widely distributed and scattered over a larger area. The habitat is skeletal and rocky and the vegetation more herbaceous than at the eastern site. The similarity of the plants to those of 7500 is close but the variation is less extreme. There is less evidence of a mutica influence and a return to more or less the maraisii/floribunda/heidelbergensis archetype.

3. MBB7503 Die Kop Mid (figs. 11a to i). The first impression I had was that the plants included more mirabiloid influence. Not as big as 7500 and also scattered on a skeletal slope. At one point there was a gravel patch with Gibbaeum austricola which is commonly found on such gravel patches associated with ferricrete inselbergs.

4. MBB7504 Die Kop North (figs 12a to k). The plants are smaller and there is a more evident floribunda influence. I did not think that these plants were significantly different from the many populations discussed in Chapter 15 between Tarentaal and Stormsvlei.

Conclusions:
It should be very evident from all the information provided so far that more information is not producing a better picture of discrete elements. To the contrary and this reinforces the conclusion already mooted, that movement to a new view of “species” in the subgenus Haworthia is necessary, but is it possible?

Acknowledgement:
Mr. Keith Spencer, DeHoop Nature Reserve.
Messrs. Christine & Malcolm Wallace, Ziekenhuis.
Mr. John Douglas-Hamilton, Ballyfar.
Mr. Johan Groenewald, Klipfontein, Potberg.
Messrs. Saartjie and Neil Neetling, Juliesfontein.
Messrs. Adele & Vlooi DuToit, Die Kop & Frederickskraal.
Messrs. Pet & Johannes Uys, Die Kop.
Messrs. Sofia & Jurie Vermeulen, Tarentaal

♦

Haworthia limifolia – a conundrum or a lesson?

Posted on March 25, 2012 by Bruce Bayer

I was contemplating the problem I see in the way we approach classification, contending that there is no resolution to the endless addition of new names and arguments about their validity and usefulness unless we reach some agreement on method and purpose. The confusion about names, descriptions and identifications that had arisen in 1947 came about for four reasons. Small samples and inadequate exploration, too many unqualified experts, lack of insight into what species actually may be, poor methodology.

There is no excuse for this situation to continue. Sampling is at a very high level and because the other three elements have not been removed, confusion is as great as before. Many names may have been lost from sight, but there is no lack of new ones to replace them. Experts are a problem and their qualifications even more so. In my own experience I have communicated with many highly qualified botanists who have contributed absolutely nothing to the resolution of problems as basic as typification of names, or definition of the word ‘species’. So what then contributes to qualification? This is surely an unbridgeable problem when amateurs have dabbled so freely in plant classification with apparent success. But their success has come from the failure of qualified botanists to put something more substantial in place than a nomenclatural code for binomials and nothing to indicate what those should mean, or who is competent to generate or change them.

Neither of those problems can be solved by me. My contribution has been to see as much as I can of what others have seen, and then to myself explore in both the arena of the subject matter and the periphery of biology that touches it. What I have done is to try and relate what I have read and been taught to what I have observed and experienced. In this way “species” have become a reality as systems of populations and individuals that are spread in space and change with time. Whether evolution is a fact or not I cannot say, but change certainly is. Classification since Linnaeus, has always been associated with this change but not necessarily by everyone. But in the time of Linnaeus, the sampling level was very low and anything new could be, or was, interpreted as a new species and diagnostics were put in place to aid identification. Hence even the Latin binomial was a diagnostic. As the sampling level has been raised so has the system come under increasing stress and it is a fallacy to think that only Haworthia is problematic. However, this is the genus under discussion here and we have to admit that the diagnostics and the methodology do not work.

H. limifolia can be used as an example to illustrate the situation.

It is to all intents isolated from the rest of the genus. We do have H. koelmanniorum sitting to the far north-west and then H. tessellata further to the south-west. Otherwise the rest of the genus is in the Cape. The issue of subgenus need not be seen as a consideration here even though the differences there are as great as any elsewhere in the family.

H. limifolia has a very wide distribution from Komatipoort in the north, westwards and southwards to Vryheid, eastwards and southwards to Gollel and then Stanger in KwazuluNatal. The whole of Swaziland and a large part of northern KwazuluNatal may harbor this species. We need to even ask … “Is it a species?”

The fact is that there are very different elements involved in respect of individual appearance and virtually all aspects of that individuality. The possibility is that whole populations may be derived from vegetatively propagating individual clones. Some plants are solitary and propagate with difficulty. Others proliferate as vegetative offsets or by stolons. The leaf shape and surfaces are highly variable. The surfaces may be flat or channeled; absolutely smooth, to having raised wave-like wrinkles, to tuberculate with small individual tubercles, or the tubercles may be fused in groups and ridges. These may be normal leaf-coloured or they may be white. Flowers are extremely variable and so are the seeds and the capsules. Flowering time seems to be opportunistic and in cultivation the plants may flower at any time, usually synchronizing during the summer months.

Do we really have any alternative but to see this as one single very large operating systems, despite all the real problems of isolation by distance and hence the associated problem of gene transfer between individuals and populations? Is it sensible or even practical to insist or suggest that there must be Latin binomials that describe (in the early Linnaean sense) the situation or, more importantly, that there are diagnostic characters by which such single taxa (groups, species, varieties, forms etc) can be identified?

How can the situation we observe in this relatively isolated system and (species?) be extrapolated to the Cape where all three subgenera and the bulk of the species occur?

Recently two authors have proclaimed the value of floral morphology in resolving this ongoing disputation about the species. What their actual view of what species are has not been spelled out but it appears to be a belief that simple structural (morphological) differences are what define them. Behind this must lie the unconscious acceptance of the original definition of species that they were systems of interbreeding or potentially interbreeding organisms. Thus flower structure is assumed to be linked to the breeding system and therefore very important in classification. This view of species still seems to be the power behind classification although it has long been recognized that in plants inter-fertility may extend across generic difference.

In Haworthia the flowers, even across the sub-genera, are fairly similar and especially in regard to size. Within the sub-genera, the similarities between what are considered to be species, is remarkable. There are even exact similarities that can be found in what are truly geographically and vegetative different populations. Flowering time seems to suggest some kind of additional factor but even here it is evident that breeding can occur between populations with flowering times 6 months apart. It has to be considered that flowering time differences like this might even be a characteristic of a species. This has in fact been shown for H. marginata and H. minima that surely can otherwise seen to be different systems.

The pollinating agents are insects and it seems as if flower size may be linked to that fact as it is so consistent across the genera and whatever are thought to be the species. Here I just present a number of pictures of the profiles and faces of flowers from 5 populations H. limifolia of which some are from different clones in those populations. A difficulty in viewing flowers is that they change with age, and place on the peduncle. They only last about three days and it is thus difficult to compare flowers of exactly the same age and condition. Of course these are poor pictures but no essential and detail is lost here by poor focus. But it is quite obvious that there is bigger difference between the two flowers (profiles) of the plants from Ithala than there is between them and other populations. Consider too that it can be very difficult to distinguish any of these flowers from those of other species in the subgenus Hexangulares. This essay is not submitted as conclusive evidence and argument and I will enlarge on this in a following essay. ♦

MBB7145 H. limifolia var glaucophylla. Three Sisters, Barberton.

Haworthia flowers – some comments as a character source, part 1

Posted on May 12, 2012 by Bruce Bayer

M B Bayer, Kuilsriver, RSA

Introduction

The object of this essay is to discuss where we are now with respect to classification of Haworthia. Despite my comments and observations stretching over 50 years, there are still taxonomists writing and arguing on the basis of method and practice that generated the anarchy of names that existed at the start of my involvement. This method is what is probably referred to as “typological” i.e. there is a single herbarium specimen and anything that departs from this in some mind catching way is a different and thus needs a new name. At the generic level, recent DNA studies show that Haworthia is indeed three separate entities (the subgenera), and that these cannot be rationally separated from the aloid genera. Formal classification requires that Haworthia thus be subsumed in Aloe (see Treutlein et al, Rhamdani et al and Daru et al). This is both incomprehensible and anathema to writers and collectors locked into method that does not rest on any insight to what the problem of species actually is, let alone take proper cognizance of the problems that exists at generic level.

In response to some of the expressed anxiety about the proposed changes to Aloe, Dr John Manning, in a personal communication, wrote…”Most folk follow the biological species concept, which in its simplest form proposes that species are groups of interbreeding populations that are more or less reproductively isolated from other species. The existence of infrequent hybrids does not invalidate it. HOWEVER this is just about always a purely theoretical construct because there is no experimental data in most species to back it up. In practice, therefore, folk use morphology as a surrogate for reproductive isolation on the argument that discontinuities in morphology will coincide with these reproductive boundaries. Naturally there are all sorts of natural variabilities within species and so it becomes tricky to decide which of them fall within the boundary of the species and which fall outside of it”.

Two interesting things arise from this. Firstly, a “species” is itself a biological entity and there are not (or should not) be species that are not biological. Secondly there is a difference between a species concept and a definition. The concept is a general idea, while a definition lays down requirements that must be met. It might be better to say…”species determined by their interbreeding potential”, than use the term “biological species”. There is a huge amount of real experience and observation of the interbreeding capabilities of Haworthia both in the field and in cultivation. This suggests that if we really followed this criterion for determining in the genus then most of the Latin species names are superfluous, as I indeed consider them to be. Therefore, while there is a problem with the formal recognition of genera, the seems to be a total vacuum in respect of considerations around the constitution of species and how they can be, or are to, be circumscribed.

I have of course based what I regard as Haworthia species on a view of species as dynamic systems in a geographic framework, because history and my own long experience suggest that there are no morphological (or biological) criteria that produce the kind of classification that writers have produced or that collectors may need or expect. I proved by my studies in Oxalis, that morphological criteria can be extremely misleading, and that characters (or even character sets) thought to be useful in delimiting species, may in fact vary more within species than between species. I observe that this is true in many other genera. Flowers have recently been touted again by aspiring taxonomists as characters that will solve problems and it has even been said that I have ignored them. This is not true. I do not deny their value as characters. My experience simply suggests that variation and similarities in floral characters, mirror the situation with regard to vegetative morphology and may actually provide evidence for further amalgamation of species and reduction of names. This essay thus explores the situation in a data set, fortuitously available by virtue of modern digital photography and opportunity.

The elemental issue underlying all of this is dependent on the species definition. If some floral character is, or characters are, identified and specified as species characters then of course they would acquire significance in that context. What I can only show is that I observe nothing of the kind to relate to such a definition and insist on as species as systems in a geographic framework. Can they be rationally organized in any other system?

The hypothesis this essay addresses is that the floral morphology can be used to identify and circumscribe taxonomic ranks in Haworthia.

Overview

Originally I very laboriously drew flowers – often only one per collection. But one of my projects was trying to find more consequential objective evidence than just subjective vegetative differences to distinguish between H. reticulata and H. herbacea. I used a range of floral measurements but found the variation so great that to get a statistically significant result would have entailed many more samples than the number I used. Doing this would have been both very labour intensive and very destructive to the populations. I must point out that I am confident I could separate H. arachnoidea, H. mirabilis, H. pubescens as well as H. herbacea and H. reticulata (to some degree), all in the Worcester area, on the basis of their flowers. But this is not the level at which any other solution is needed beyond the appearance of the plants. There are only general differences by which one can separate H. herbacea and H. reticulata in respect of both vegetative and floral characters. H. wittebergensis could probably be identified just on the basis of its small white and more recurved flower, but its vegetatitve characters are quite adequate for the purpose.

Photography in those early days was not an option for recording flower detail. The advent of digital photography changes that quite dramatically and this essay is an exercise using this technology to attempt to document field observations. I photographed flowers as available in approximately 30 populations during February 2012, and these are used now in a posteriori manner to test the hypothesis regarding flowers. These images cover three species as I recognize them as systems in a geographic context viz. H. mirabilis (20 populations from three geographic zones), a summer flowering set of H. mutica (3 populations), H. floribunda (5 populations). Several outlier populations are added although sometime by single clones (see Table 1 listing the accessions. Map 1 (at end) indicates relative geographic position). These photographs provide a pictorial record of variation and difference within populations, between populations of the same species and between populations of different species.

Data

1. The plants. Figure Set 1 is a set of to 4 each, of the plants as they are in the populations covered. I have done this as a reference to how the names were derived and as I use them. The plants are far more variable than is generally understood and four images per population is really grossly inadequate as a sample to base a circumscription on. In the case of 7163 H. mirabilis, Frehse Reserve, S Riversdale, I have included pictures of plants (no flowers) because this is the type locality for the name H. magnifica (=H. mirabilis) that is widely used without any consideration of the range of variants there and how they may relate to other populations of H. mirabilis that are equally variable. Curiously there were no flowers and it appeared that the few plants that had flowered had done so earlier than expected. The same applies to a very similar population 6651 from a little to the southwest where there was only a single open flower. But two other populations viz. 7778 and 7818 in the area had many flowers at the time. It was rather similar at Van Reenens Crest where the various populations had not flowered with equal vigour and at some it was not possible to get a respectable number of flowers. It should be noted that in a good season with some summer rain, the plants will flower more successful with more plants flowering and some plants producing successive inflorescences. Thus the flower season could be extended be several weeks. Note that in the case of 7976 H. floribunda I did not take plant pictures for this second population.

Table 1. List of populations and identifications.

1. Haworthia mirabilis – eastern zone, Riversdale area (cf H. magnifica).
6651 H. mirabilis, E Riversdale.
7163 H. mirabilis, S Riversdale.
7778 H. mirabilis, Komserante, E Riversdale.
7818 H. mirabilis, Windsor, SE Riversdale.
7809 H. mirabilis, Koeisekop, Heidelberg.

2. H. mirabilis – central zone, Swellendam area.
7887 H. mirabilis, Rotterdam.
7912 H. mirabilis, Rietkuil.
7913 H. mirabilis, Rietkuil.
7916 H. mirabilis, Van Reenens Crest.
7917 H. mirabilis, NE Dam VR Crest.
7918 H. mirabilis, Van Reenens Crest, SE Dam.
7919 H. mirabilis, Van Reenens Crest, Game camp.
7955 H. mirabilis, Van Reenens Crest.
7959 H. mirabilis, W Van Reenens Crest.
7960 H. mirabilis, Kruiskloof.

3. H. mirabilis – western zone, Greyton area (cf. vars beukmannii, rubrodentata).
7262 H. mirabilis, S Greyton.
7978 H. mirabilis, Schuitsberg.
7979 H. mirabilis, Nethercourt.
7980 H. mirabilis, E Ouplaas.
7981 H. mirabilis, Schuitsberg N.

4. H. mutica – north-eastern zone, Buffeljags (Swellendam area, cf. H. groenewaldii).
7801 H. mutica, Buffeljags.
7888 H. mutica, Rotterdam 1.
7889 H. mutica, Rotterdam 2.

5. H. floribunda – central zone, Swellendam area.
7774 H. floribunda, S Swellendam.
7910 H. floribunda, Rietkuil.
7963 H. floribunda, Niekerkshek.
7975 H. floribunda, Rotterdam 1.
7976 H. floribunda, Rotterdam.

6. H. mirabilis – outliers and ‘outgroups’.
7248 H. mirabilis, Ballyfar, Infanta.
7513 H. mirabilis, Klipfontein N Bromberg.
7612 H. mirabilis, Diamant W.
7780 H. retusa ‘geraldii’, Komserante.
7781 H. retusa ‘foucheii’, Komserante.
7920 H. retusa ‘ nigra’, Van Reenens Crest.
7974 H. mirabilis, Klipfontein, Potberg.
7982 H. mirabilis, Melkhoutkraal, Goukou.
JDV87-132 H. parksiana, Mossel Bay.

The plant images :-

SET 1. H. mirabilis, Eastern Zone.

6651 H. mirabilis, SW Riversdale

7163 H. mirabilis, Frehse Reserve, S Riversdale

7778 H. mirabilis, Komserante

7818 H. mirabilis, Windsor

7809 H. mirabilis, Koeisekop

SET 2. H. mirabilis, Central Zone.

7887 H. mirabilis, Rotterdam

7912 H. mirabilis, Rietkuil

7913 H. mirabilis, Rietkuil

7916 H. mirabilis, Van Reenens Crest

7917 H. mirabilis, Van Reenens Crest

7918 H. mirabilis, Van Reenens Crest

7919 H. mirabilis, Van Reenens Crest

7955 H. mirabilis, Van Reenens Crest

7959 H. mirabilis, Van Reenens Crest

7960 H. mirabilis, Kruiskloof

SET 3. H. mirabilis, Western Zone.

7262 H. mirabilis, S Greyton

7978 H. mirabilis, Schuitsberg

7979 H. mirabilis, Nethercourt

7980 H. mirabilis, E Ouplaas

7981 H. mirabilis, Schuitsberg N

SET 4. H. mutica in its NE zone, Swellendam.

7801 H. mutica, Buffeljags

7888 H. mutica, Rotterdam 1

7889 H. mutica, Rotterdam 2

Set 5. H. floribunda in its western zone, Swellendam.

7774 H. floribunda, S Swellendam

7910 H. floribunda, Rietkuil

7963 H. floribunda, Niekerkshek

7975 H. floribunda, Rotterdam 1

7976 H. floribunda, Rotterdam – not illustrated.

SET 6. Outliers H. mirabilis and some relevant populations.

7248 H. mirabilis, Ballyfar

7513 H. mirabilis, Klipfontein, N Bromberg

7612 H. mirabilis, Diamant

7720 H. retusa ‘nigra’. Van Reenens Crest

7982 H. mirabilis, Goukou

JDV87132 H. parksiana, Mossel Bay

Haworthia flowers – some comments as a character source, part 1

Haworthia flowers – some comments as a character source, part 2

Haworthia flowers – some comments as a character source, part 3

♦

Haworthia flowers – some comments as a character source, part 2

Posted on May 12, 2012 by Bruce Bayer

2. THE RACEME. Figures Set 2 show the bases of the peduncles in several collections to again show how variable they are and not only because of plant vigor and current growth conditions. Diameter can vary by a factor of three. Color is variable and the bract spacing and size of bracts as variables must be noted. Fig 6 is simply a robust spike in a population where the flowers were sparsely spaced on the stem with approximately 15-20 flowers per stem, whereas this raceme had nearly 30 flowers. The number can drop to as low as three. In 7917 we noted a single plant with an inflorescence of over 600mm where the average was below 300. Similarly at 7818 there was one colossal inflorescence of 800mm where again the average was between 300 and 400mm. There is a real problem in that the typological attitude is often adopted when making comparisons like this. An extreme example would be to take H. retusa south of Riversdale as typical of the species. These are massive plants (source of ‘Jolly Green Giant’) and the inflorescences are huge with many flowers. This is not typical for the species and especially so if one takes the mountain cliff populations (H. turgida) to be the same species (as I do) where the plants are proliferous and the inflorescences many and reduced. Plants in poor niches and even poor habitats, flower weakly and the inflorescences are reduced. Figs 7 shows varying capsule positions on the stem. Figs 8 and 9 show a distichous and a secund inflorescence and figs 10 to 15 demonstrate the varied spacing of the flowers that is observable even in any one population although the images are for two different accessions. In Fig. 8 the middle flowers are in a single plane and I regret not having observed the leaf arrangement in that specific plant, because this is a distichous arrangement as the low Fibonacci number of a spiral arrangement of the flowers. This may have been reflected in the leaf arrangement too. The spacing and arrangement of the flowers is also a variable and the number of flowers may also vary. Figs 16 to 18 show bud arrangement and the way in which the fish-tail buds have upturned tips. Although the peduncle does continue to lengthen, most of the lengthening takes place in the flower producing area and towards the upper end of the raceme. The peduncle does not always stay straight and may bend slightly at each floret. The number and distance of the flowers along the peduncle may affect bud packing just as peduncle formation in the rosette results in the appearance of a groove on the leaf face. This is a secondary physical phenomenon and is not an inherent “character”. The leaf keel for example may also be influenced just by physical leaf-packing. A peduncle of a flower from the centre of a plant will have a many angled base, but one arising from a leaf axel only 2-angled. Generally the raceme is indeterminate, meaning that it does not end in a pedicel and flower. But I have seen an individual raceme of H. floribunda with a terminal flower. This exemplifies our problem where characters one might think could be used to determine even genera, are variables at species level.

2.1 7075 H. mutica, Grootvlakte
2.2 7262 H. mirabilis, S Greyton
2.3 7955 H. mirabilis, Van Reenens Crest

2.4 7778 H. mirabilis, Komserant
2.5 7809 H. mirabilis, Koeisekop

2.6 7913 H. mirabilis, Rietkuil
2.7 7919 H. mirabilis, Van Reenens Crest
2.8 7918 H. mirabilis, Van Reenens Crest
2.9 6509 H. mirabilis, W Bonnievale

2.10 7809 H. mirabilis, Koeisekop
2.11 ADH2729 H. mutica, De Hoop
2.12 7959 H. mirabilis, W Van Reenens Crest

2.13 7075 H. mutica, Grootvlakte
2.14 7741 H. mutica, Dankbaar
2.15 7920 H. retusa ‘nigra’, Van Reenens Crest

2.16 7781 H. retusa ‘fouchei’, Komserante
2.17 7778 H. mirabilis, Komserante
2.18 7818 H. mirabilis, Windsor

3. THE BRACTS. Figures Set 3. Bracts occur from the very base of the peduncle and subtend each flower. The bracts vary in density and size and one should recall J.R. Brown’s complaint that the plant he illustrated as H. schuldtiana var. major could not be that variety because the bracts were not the same length specified by G.G. Smith in the description. Although the bracts are attached to the stem, sometimes the stem is slightly swollen as though to form a base for the pedicel and occasionally the bract seems to be attached to that as though recaulescent (Fig.3.1). Usually there is a short pedicel but these do differ in length and width (figs 6 & 7, 8 & 9) within populations so that the florets may sit against the stem and in others away from it on a pedicel 3-4mm long (figs 2&3, figs 3,4 & 5). This is again an example of what might have been a primary character i.e. stipitate vs pedicellate, separating species, as a variable within a species. The bract may be quite narrow but may also be broad and almost encircle the stem (figs 12 & 13). The margins of the bracts may be entire or serrated in the same population and other oddities do occur (figs 8 & 9).

3.1 7262 H. mirabilis, S Greyton
3.2 7818 H. mirabilis, Windsor
3.3 7818 H. mirabilis, Windsor

Bract recaulescence? Note bract positions.

3.4 7918 H. mirabilis, Windsor
3.5 7918 H. mirabilis, Windsor
3.6 7919 H. mirabilis, Van Reenens Crest

Note presence or absence of pedicel.

3.7 7919 H. mirabilis, Van Reenens Crest
3.8 7919 H. mirabilis, Van Reenens Crest
3.9 7963 H. floribunda, Niekerkshek

Double bract

3.10 7818 H. mirabilis, Windsor
3.11 7818 H. mirabilis, Windsor
3.12 7778 H. mirabilis, Komserante

Variation in bract size. Bract almost wrapping peduncle.

3.13 7960 H. mirabilis, Kruiskloof Bract tucked under flower

4. THE BUDS. Figures Set 4. These figures illustrate the bud-tip as it occurs in most of the south-western Cape species. This flattened split tip is most evident in H. herbacea and H. reticulata but also present in H. maculata, H. retusa, H. mirabilis, H. mutica and H. pygmaea, but not in H. floribunda, H. rossouwii and H. variegata. The bud also is often slightly double-arched, bending first downward and the upward again especially evident in the bud of H. mirabilis 7248 Ballyfar. However, this is not quite an absolute and in some buds the character is not clearly flattened or may even be a bit rounded. I am not confident that my observations are entirely correct as I dismissed any floral characters quite early in my exploration when it was apparent to me that using a geographical approach might first tell me something about species from which I could then infer importance of characters of any kind. The effect of the flattened tip is to compress the tips of the upper petals, but in H. herbacea and H. reticulata the petal tips are quite spreading, whereas in H. mirabilis they tend to align vertically even folding behind the upper inner.

SET 4–BUDS

Subset 1. Haworthia mirabilis – eastern zone, Riversdale area (cf. H. magnifica).

7818 H. mirabilis, Windsor, SE Riversdale. (3)

7809 H. mirabilis, Koeisekop, Heidelberg. (3)

Subset 2. H. mirabilis – central zone, Swellendam area.

7916 H. mirabilis, Van Reenens Crest
7917 H. mirabilis, NE Dam VR Crest
7918 H. mirabilis,Van Reenens Crest, SE Dam
7959 H. mirabilis, W Van Reenens Crest

Subset 3. H. mirabilis – western zone, Greyton area
(cf. vars. beukmannii, rubrodentata).

7978 H. mirabilis, Schuitsberg

Subset 4. H. mutica – north-eastern zone, Buffeljags
(Swellendam area, cf. H. groenewaldii).

7801 H. mutica, Buffeljags. (3) 7889 H. mutica, Rotterdam 2.

Subset 5. H. floribunda – central zone, Swellendam area.

7774 H. floribunda, S Swellendam. 7963 H. floribunda, Niekerkshek.

Subset 6. H. mirabilis – outliers and ‘outgroups’.

7248 H. mirabilis, Ballyfar, Infanta. (2) 7612 H. mirabilis, Diamant W. (2)

7780 H. retusa ‘geraldii’, Komserante
7781 H. retusa ‘foucheii’, Komserante
7974 H. mirabilis, Klipfontein, Potberg

7982 H. mirabilis. , Melkhoutkraal, Goukou
JDV87-132 H. parksiana, Mossel Bay

5. THE FLOWERS. Figures Set 5a and 5b

5a. Flower progression. Figures set 5a illustrate the ageing progression in two florets from two populations. One of the biggest hurdles in describing or illustrating the flower is the change that takes place that occurs in the life of the flower from bud opening to flower wilting over a period of 4-6 days. As can be seen in these successive images, the petal spread wider with age. But clearly there is a difference in basic structure of the individual flower that also determines attitude of the petals through the various stages. Colour and texture of the flower may also vary as the flower loses turgidity with aging and wilting.

5a.1 7913 H. mirabilis, Rietkuil

5a.2 7963 H. floribunda, Van Niekerkshek

Flower length in mm

5910	7918	7513	7262
14.3	13.5	11.8	14.5
13	13.5	12.1	13.7
12	13	12	14.6
12.5	13.4	12.5	14.6
14	13.1		13.4
13	13.4		15
13	13.2		15.3
14	13.2		16.8
12.5	13		16.7
14.2	12		15.3
12.5	12.8
13.5	12.5
12	12.4
14	12.6
13.5	12.5
	12.3
	12.5
	12

Fig. 5a.3 Table – headed by collecting nos. Flower length in mm.

5b. Flowers. Figures Set 5. Flowers were photographed as available using fixed lens settings so that images were reasonable comparable. Some were taken and seized against a similarly photographed millimeter rule and these measurements are given in Figure 5a.3 above as a general guide to size and variation. This was only done for 4 sets of flowers because it is very evident that my original observation of variability of a high order is true. The measurement is simply of the maximum length of the flower from attachment to pedicel to furthest upper tip in four collections. Obviously this is not ideal as how the upper petals reflex (and with age too) will distort the result. But I used it, and submit it to provide a scale for any other measurement of those given flower that one would like to make. Smaller dimensions using a millimeter ruler are not remotely accurate enough over the error already present arising from method. The sizes given in species descriptions in the archaic way still practiced, are fairly useless as there is no indication of precision and any statistical measure of inherent deviation. The photographing method, despite changes also inherent in the picture editing process, allows reasonable size comparisons. The fact is that across the three subgenera, tube length is consistently in the area 8-10mm probably corresponding to a common pollinator. An important consideration is also that of the requirements of a sampling process in statistics where randomness is essential. The tendency in the field is to be selective and this generates the problem of bias that is almost unavoidable even when this is considered.

A point that must be stressed is the question of plant condition on whatever structures are used for study. Generally if a plant flowers at all, it can be assumed that the condition of the plant was good enough and the flower appearance would be true. This is an assumption carried into most studies of herbarium material and generally accepted as valid. But when decisions are based on the nature of whole inflorescences, it becomes quite evident that plants in different niches and habitats, and even different seasons, will produce inflorescences according to plant vigour. Over and above this is the variability that derives from habitat adaptation. Proliferating ecotypes on well-drained cliff-faces will produce quite a different inflorescence to that of solitary ecotypes in deeper moisture-holding soils. Flowers on an inflorescence lasting 3-4 days from initial petal spread to wilting also change with time. The position on the flower is also significant as the terminal flowers are invariably smaller. Another problem is the assumption that characters are independent. The fact is that, say, the bud-tip is flattened. Petals contained in that bud-tip are constrained to fold accordingly and if the petals vary in width or length they will display differently simply because of the containment within the bud-tip.

The populations listed in Table 1 were visited during February when they were in flower, and a series of flowers photographed in each population as available. Each flower was photographed in profile and from face view with the camera lens at a fixed focus setting. It is just a fact that all Haworthia flowers are closely the same in respect of size as stated above. I am aware of smaller flowers in H. wittebergensis, as one example, and also very large flowers to nearly 30mm long (against an average of approximately 15-20mm) in H. herbacea from Villiersdorp. The numerical measurements are variable and while there is no doubt that these could be found if sought, the intention here is to show that they are unlikely to help resolve the issues of species differences at the level that they are needed. This is certainly not without very large samples and precise measurement to accuracy of at least 0.1mm. Some observations were recorded as described above of peduncles, capsules and seeds. But only to indicate that they have been considered and also regarded and seen as variables that are unlikely to make any contribution by virtue of the degree of similarity they show even over the few species involved in the observations. What differences are discernible are highly unlikely to have any significance when one thinks that these have to be shown to exist consistently in very similar structures over many populations and many species.

The largest differences one would expect to see should be in the individual flowers (florets). Pictures were thus taken of the flowers in profile and also of the facial aspect. Size is a variable and Fig. 5b.1 shows three flowers from different clones in 7910. Fig. 5b.2 shows two flowers from the base and tip of a single inflorescence in 7980 – the upper floret half the size of the lowest. Fig. 5b.3 is a diagram to show profile and face of a flower (6651) to suggest axes along which a flower could be orientated to obtain proper points of reference for measurements of angles or size. The face and profile are of 6651, but the three part flower bases are all from the same collection. These virtually sum up the entire argument as the diagrams show a floret without a petiole, and various shapes to the base of the tube that I refer to as the perigon – the section before the petals separate. The taper from the pedicel onward (the stipa?) is very variable and may be abrupt or extended. The tube may be uniformly deep or constricted at the middle. A pronounced swelling (gaster) of the tube may occur below near the base. Other variables are the angle at which the flower stands to the peduncle. This one rather complicates the imaging of the face as I tried to photograph holding the camera at right angles to the peduncle and that does not properly capture a flower that is very vertical.

The sequence of illustrations onwards from 5b.4 is first the faces and then the profiles of the flowers according to the listing of the sets of populations in Table 1.

SET 5B.4 – FACES

Subset 1. H. mirabilis – Eastern Zone, Riversdale area.

6651 H. mirabilis, SW Riversdale

7778 H. mirabilis, Komserante

7818 H. mirabilis, Windsor

7809 H. mirabilis, Koeisekop

Subset 2. H. mirabilis – Central Zone, Swellendam area.

7887 H. mirabilis, Rotterdam

7912 H. mirabilis, Rietkuil

7913 H. mirabilis, Rietkuil

7916 H. mirabilis, Van Reenens Crest. 7917 H. mirabilis, Van Reenens Crest.

7918 H. mirabilis, Van Reenens Crest

7919 H. mirabilis, Van Reenens Crest

7955 H. mirabilis, Van Reenens Crest

7959 H. mirabilis, Van Reenens Crest

7960 H. mirabilis, Kruiskloof.

Subset 3. H. mirabilis – Western Zone, Greyton area.

7262 H. mirabilis, S Greyton

7978 H. mirabilis, Schuitsberg

7979 H. mirabilis, Nethercourt

7980 H. mirabilis, E Ouplaas

7981 H. mirabilis, Schuitsberg N

Subset 4. H. mutica – Northeastern Zone, Buffeljags area.

7801 H. mutica, Buffeljags

7888 H. mutica, Rotterdam 1

7889 H. mutica, Rotterdam 2

Subset 5 H. floribunda – Central Zone, Swellendam area.

7774 H. floribunda, S Swellendam

7910 H. floribunda, Rietkuil

7963 H. floribunda, Niekerkshek

7975 H. floribunda, Rotterdam 1, 7976 H. floribunda, Rotterdam

Subset 6. Outliers and ‘outgroups’.

7248 H. mirabilis, Ballyfar

7513 H. mirabilis, Klipfontein, Bromberg

7612 H. mirabilis, Diamant W

7780 H. retusa, Komserante. 7781 H. retusa, Komserante. 7915 H. mirabilis,Van Reenens Crest

7920 H. retusa ‘nigra’, Van Reenens Crest
7974 H. mirabilis (‘floribunda’), Klipfontein, Potberg
7982 H. mirabilis, Goukou

87-132 H. parksiana, Mossel Bay
7937 H. mutica, Spitzkop, Bredasdorp

SET 5B.4- PROFILES

Subset 1. H. mirabilis – Eastern Zone, Riversdale area.

6651 H. mirabilis, SW Riversdale

7778 H. mirabilis, Komserante

7818 H. mirabilis, Windsor

7809 H. mirabilis, Koeisekop.

Subset 2. H. mirabilis – Central Zone, Swellendam area.

7887 H. mirabilis, Rotterdam

7912 H. mirabilis, Rietkuil

7913 H. mirabilis, Rietkuil

7916 H. mirabilis, Van Reenens Crest. 7917 H. mirabilis, Van Reenens Crest.

7918 H. mirabilis, Van Reenens Crest

7919 H. mirabilis, Van Reenens Crest

7955 H. mirabilis, Van Reenens Crest

7959 H. mirabilis, Van Reenens Crest

7960 H. mirabilis, Kruiskloof

Subset 3. H. mirabilis – Western Zone, Greyton area.

7262 H. mirabilis, S Greyton

7978 H. mirabilis, Schuitsberg

7979 H. mirabilis, Nethercourt

7980 H. mirabilis, E Ouplaas

7981 H. mirabilis, Schuitsberg N

Subset 4. H. mutica – Northeastern Zone, Buffeljags area.

7801 H. mutica, Buffeljags

7888 H. mutica, Rotterdam 1

7888 H. mutica, Rotterdam 2

Subset 5 H. floribunda – Central Zone, Swellendam area

7774 H. floribunda, S Swellendam

7910 H. floribunda, Rietkuil

7963 H. floribunda, Niekerkshek

7975 H. floribunda, Rotterdam 1. 7976 H. floribunda, Rotterdam.

Subset 6. Outliers and ‘outgroups’.

7248 H. mirabilis, Ballyfar

7513 H. mirabilis, Klipfontein, Bromberg

7612 H. mirabilis, Diamant W

7780 H. retusa ‘geraldii’, Komserante
7781 H. retusa ‘foucheii’, Komserante
7915 H. mirabilis, Van Reenens Crest

7920 H. retusa ‘nigra’, Van Reenens Crest
7974 H. mirabilis (‘floribunda’), S Klipfontein, Potberg
7982 H. mirabilis, Goukou

JDV87-132 H. parksiana, Mossel Bay

Haworthia flowers – some comments as a character source, part 1

Haworthia flowers – some comments as a character source, part 2

Haworthia flowers – some comments as a character source, part 3

Posted on May 12, 2012 by Bruce Bayer

6. THE CAPSULES. Figs 6.1 first size differences that can be found within individual inflorescences. The remaining images show 8 capsules per population for a few populations to show variation in size and shape. The way the capsule ripens and splits is very variable. In some cases the capsule is pinched near the end but the locule tips flare outwards. This has the effect of seeds being retained in the capsule. In others the locules flare regularly and symmetrically from the base and the seed is all easily released. In the Van Reenen Crest populations the capsules were inclined to be a reddish hue. But colour can vary depending on the ripening process and they also bleach with time. Fig.6.4 7978 shows this in capsules drying after the peduncle was taken, and retaining their greenish colour. In H. floribunda the capsules are smaller and it appears that they may flare at the tips more in splitting and be coarsely crispate. This is not always the case but it is a tendency in the smaller capsules to do this. Fig. 6.7 is of capsules in 7910 H. floribunda, Rietkuil; compared against 7913 H. mirabilis also Rietkuil east of Swellendam. It is quite evident that even a capsule structure as apparently characteristic as in H. floribunda, is replicated in a different species. Fig. 6.8 is of 7955 Van Reenens Crest, and 7262 south of Greyton. I thought the capsules of 7955 were smaller, reddish coloured and slightly rougher than those of 7262. But the capsule structure in the entire genus is very similar to those shown on this figure and it is just not conceivable that some feature will stand out and resolve issues that exist in respect of the entire group.

7163 H. mirabilis, S Riversdale. 7809 H. mirabilis, Koeisekop.
Fig. 6.1 Size variation – range 5-12mm.

6651 H. mirabilis, SW Riversdale
7163 H. mirabilis, S Riversdale
7778 H. mirabilis, Komserante

7818 H. mirabilis, Windsor
7809 H. mirabilis, Koeisekop
Fig. 6.2 H. mirabilis – Eastern Zone, Riversdale area.

7913 H. mirabilis, Rietkuil
7919 H. mirabilis, Van Reenens Crest
7959 H. mirabilis, Van Reenens Crest
Fig. 6.3 H. mirabilis – Central Zone, Swellendam area.

7262 H. mirabilis, S Greyton. 7978 H. mirabilis, Schuitsberg
Fig. 6.4 H. mirabilis – Eastern Zone, Greyton area.

L(1) 7888 H. mutica, Rotterdam.7910 H. floribunda, Rietkuil
R(2) 7889 H. mutica, Rotterdam
Fig. 6.5 H. mutica – Buffeljags.Fig. 6.6 H. floribunda – Swellendam.

Above 7910 H. floribunda, Rietkuil. Above 7955 H. mirabilis, Van Reenens Crest
Below 7913 H. mirabilis, Rietkuil. Below 7262 H. mirabilis, S Greyton
Fig. 6.7 Some capsule comparisons.

7. THE SEEDS. Some seeds are illustrated in figures Set 7. Any differences there might be in the seeds will be extremely difficult to quantify or describe. There is clearly some difference in size but to establish this statistically will be difficult. In the set of pictures provided there is clearly no difference in appearance or size coupled with the fact that the shape beyond “angular” and colour “grayish black” is difficult to articulate. What size difference appears here is due to picture magnification. Again I am quite aware that in some populations seeds are indeed larger than in others, but vegetative characters are already enough to distinguish those. Species recognition would only be facilitated if one based the definition of the species on some formula specifying seed size and shape. In the figure, 7983 is the seed of H. minima to show the quite different flattish shape and marginal wings in that subgenus. My impression was that the seed in H. floribunda may be a little chunkier than in the other samples but it just does so happen that in some capsules there are fewer and larger seed than in others.

SET 7 – SEEDS

1 – 6651 H. mirabilis, 1 – 7163 H. mirabilis, 1 – 7778 H. mirabilis

1 – 7809 H. mirabilis, 1 – 7818 H. mirabilis, 2 – 7912 H. mirabilis

2 – 7913 H. mirabilis, 2 – 7919 H. mirabilis, 2 – 7959 H. mirabilis

3 – 7262 H. mirabilis 3 – 7978 H. mirabilis 3 – 7980 H. mirabilis

4 – 7888 H. mutica, 4 – 7889 H. mutica, 5 – 7910 H. floribunda

5 – 7963 H. floribunda, 6 – 7982 H. mirabilis, L.7262 H. mirabilis, R.7955 H. mirabilis

6 – L.7910 H. floribunda, R.7913 H. mirabilis, 7283 H. minima

DISCUSSION AND CONCLUSIONS
While assembling and sorting the data sets I was made painfully aware of how necessary it was to keep tabs on each item. This because the similarities of between structures in very different populations was so close that without label identification, it was not possible to re-sort images into original order. Starting with flowering time that I have not yet mentioned here, as I have been dealing essentially with populations flowering in February. The southwestern Cape species of the subgenus Haworthia flower either in spring or late summer. This is the essential difference between what I regard as H. retusa (sensu lato – in the broad sense to include H. turgida) and H. mirabilis (also sensu lato to include H. magnifica, H. maraisii and H. heidelbergensis). The former set of populations flowers in the spring and the latter in late summer. But the actual time is a bit variable too as I have seen populations of the spring flowerers doing so as early as June and as late as October, while the summer group can flower from November to April. In addition there are odd plants that just flower ‘out of season’ and field hybrids present within populations of the two sets is evidence of this. It is evident from distribution, vegetative appearance and even flowering time that the two species H. retusa and H. mirabilis are parental in the origins of H. pygmaea in the east (Mossel Bay) and H. mutica in the west (Caledon). So the data here really only addresses the issue of H. mirabilis and its internal relationships, and its relationship to H. mutica in the northeastern populations. This is where one population (viz. 7801) is claimed to be a distinct species viz. H. groenewaldii. The one population 7778 H. mirabilis at Komserante obviously judging from the vegetative appearances, is infused with H. retusa. It is instructive then to look at the only two flowers I have of two nearby populations of H. retusa viz. 7780 and 7781 (see subset 6 of set 5a and 5b)

To what extent this data will influence this last mentioned claim is unknown. I simply have not and cannot discuss the floral structures in detail. This is primarily because they are so incredibly variable. I find virtually the same detail in any of the sets of figures I care to consider. What I would say that my data reflects is the interaction and continuities that I maintain are mirrored in the overall physical appearance of the plants. I have never considered 7801 H. mutica, Buffeljags as anything less than new or as anything more than the expected connection between the original H. mutica var. nigra (now H. retusa var. nigra, south of Heidelberg) and true H. mutica from the wider Bredasdorp and Caledon areas. What I did speculate was the possible involvement of H. floribunda given the distribution of that species and its interaction with both H. retusa and H. mirabilis throughout its distribution range.

I am sure this limited data set, illustrates the possible truth of my rationalization of the relationships of the plants considered. I am simply unable to extract any single point by which I can circumscribe even one population. A possible exception may be 7248 H. mirabilis, Ballyfar in which the colour yellow seems to dominate. But I recall my early involvement in Haworthia when I thought I could possibly separate H. mirabilis and H. maraisii on the basis of their flowers; with the latter having smaller and greener flowers. However, I could not do this an observations on more populations suggested to me this was just geographic variation – NOTE – differences may simply be characeristics of a species and not necessariiy denote different species. This may even apply to flowering time.

My conclusion confirms what originally impressed me. Generally flower characters will not resolve the difficulties of species circumscription based on the method, way of thinking, motives and rationale that has prevailed since Haworthia were first observed and described. Flower morphology is supposed to be central to the Linnaean method in view of their significance in the breeding process. At Buffeljags, the geographic centre of my ‘study’ area, there are close populations of H. mutica, H. mirabilis and H. floribunda across a distance of less than 600m. The plants flower synchronously and the same pollinator is present and was observed at virtually all the populations included in the entire study. H. minima and H. marginata also both occur and hybridize there too. I have up to now concluded that H. floribunda is in any case deeply infused to the point of merging into H. mirabilis both south of Heidelberg and around Swellendam. This new information, including a population pictured and reported by J. Duncan of Kirtsenbosch (nearby but within the Bontebok Park), confirms that H. floribunda is definitely interactive with H. mirabilis. My original perception of 7801 H. mutica, Buffeljags, was that it originates in the interbreeding of the three species H. retusa, H. mirabilis and H. floribunda. BUT this is not in the sense of a post speciation event where the three elements have arrived progressively at individuation as species. It is the result of the large-scale and all-encompassing process by which one gene pool has hived off H. retusa and H. mirabilis and these in turn have hived off H. pygmaea and H. mutica. The argument that 7801 H. mutica, Buffeljags is nearer to H. mirabilis than it is to H. retusa has no merit. I have in the Update Volumes explained that H. mutica is very closely allied to H. mirabilis as evident from variants seen in the field. In any case the argument rests on a typological approach where very narrow limits are attached to species names. My concept of species has developed from the plants as I have experienced them in the field, and I have not imposed any predetermined species concept on them. This study gives strength to my argument that species are complex chaotic fractal systems and that this is the model on which classification and nomenclature must be based.

(Note – a method to get more accurate mensuration would be to photograph at fixed focal length, and photographing also a millimeter rule at the same setting as I have done. However, the pictures must then be used unedited and at higher magnification more precise measurements will be attainable).

ACKNOWLEDGEMENT
I would like to thank Lawrence Loucka for his interest in the subject and his comments and advice on the manuscript. Jannie Groenewald also accompanied and assisted me in the field, as did both Lawrence and Kobus Venter. Landowners were generous with permission and I particularly acknowledge Hesphia and Trevennan Barry of Van Reenens Crest, Nelis Swart of Postdal (Kruiskloof), Leanne and Pieter Urschel of Klipfontein, Johannes and Wilmien van Eeden of Windsor, Mathewis Odendaal of Diamant, Mark and Ryno Stander of Komserante, Wimpie and Nelie Jacobs of Koeisekop, S. Smuts of Nethercourt and P.G. Viljoen of Schuitsberg.

References

Bayer, M.B., & Manning, J.C. Rationalization of species names in Haworthia. 2011. Haworthia Update Vol 7, part 4. Alsterworthia.

Daru, B. H., Manning, J.C., Boatwright, J.S., Maurin, O., Maclean, N., Kuzmina, M., & van der Bank, M. 2011. Phylogeny of the subfamily Alooideae (Asphodelaceae): Paraphylly of Aloe and Haworthia and consequences for classification. In ms.

Treutlein, J., Smith, G.F., van Wyk, B.E. & Wink, M. 2003a. Evidence for the polyphyly of Haworthia (Asphodelaceae subfamily Alooideae: Asparagales) inferred from nucleotide sequences of rbcL, atkK, ITS1 and genome fingerprinting with ISSR PCR. Pl.Biol. 5:513-521.

Treutlein, J., Smith, G.F., van Wyk, B.E. & Wink, M. 2003a. Phylogenetic relationships in Asphodelaceae (ubfamily Alooideae) inferred from chloroplast DNA sequences (rbcL, matK) and from genomic finger-printing (ISSR), Taxon 52:193-207.

Rhamdani, S., Barker, N.P. & Cowling, R.M. 2011. Revisiting monophyly in Haworthia Duval (Asphodelaceae): incongruence, hybridization and contemporary speciation. Taxon 60: 1001-1014.

♦

Haworthia flowers – some comments as a character source, Appendix 5

Posted on May 12, 2012 by Bruce Bayer

Haworthia mutica, Sandrift, Drew MBB8018 = KG226/70 = JDV92/64

This is an unusual population in that it is the most northwestern one known although only about 15km from Klipport nearer Stormsvlei. It is the source of the single plant that developed gross milkiness and for which I coined the name “Silver Widow”. The population was first recorded by a Mr. Meiring who worked as a nurseryman for the Bonnievale Nursery of Hurling and Neil in the years at least prior to World War 2. There is a letter in the Compton Herbarium archive which records a transaction between Meiring and Triebner of 100 plants as 1s ea. (i.e. = 10 cents in today’s currency.). I really struggled to find plants again in a very disturbed area and eventually did so after I had placed “Silver Widow” there in her pot to see if the flowers would be pollinated in situ. Indeed they were and then found about 20 plants in a very small area nearby. This visit owes to the report by Jakub Jilemicky of still more plants a very short distance again from these. Here there are about 80 plants in an area of about so many square meters.

Illustrations of the plants and flowers are given. The only comment I can make is to repeat that I never ignored the flowers out of ignorance. The fact is that we have a number of pretentious experts who have no concept of species other than an inherited vague notion that species have something to do with the capacity to interbreed. The fact that Haworthia plants do so freely does not handicap their enthusiasm for new species either. So this is a bit of irony. My contention was that if you did consider flowers there would be a lot less species than even in my conservative approach. In fact I am quite sure a competent professional taxonomist might well consider that I have been too generous with species and too kind to my critics.

(image files mislabeled as 8012, but are 8018 – ed.)

Acknowledgement
I thank Gerhardt Swart for access to the site and to Jakub Jilemicky for informing me of the new find. ♦

Haworthia flowers – some comments as a character source, Appendix 6

Posted on May 12, 2012 by Bruce Bayer

Two further records and data for Haworthia mirabilis.

Kobus Venter drew my attention to a second population of H. mirabilis on the eastern boundary of the farm Schuitsberg, which is the origin of the var. beukmannii of von Poellnitz. But the real motive for exploration in that area was a photograph sent to me by Messrs. Daryl and Priscilla Hackland of a plant on the Zigzag Path just east of the northern end of the town of Greyton. It was their son Andy Hackland who observed the plants and thought I might be interested – indeed. The bright green colour of the plant struck me as most unusual for that area where most of the populations known are south of the river in shale and they are of the brown and red hues. This is not strictly true because records of an expedition by Messrs. Beukman, Otzen and others mentions a small “black” species just before the entrance to Greyton. I have never found that.

However, it is well known that Haworthia mirabilis occurs along the course of the Boesmansrivier on the way to MacGregor. I once observed it there myself hiking part way from the northern end of the walking trail down the river to Greyton. Kobus Venter has also seen it while walking from the southern end. I included this variant under the varietal name ‘consanguinea’ that is actually based on populations on the north side of the mountain in the Dwarswaterkloof west of MacGregor. Ms. Dawn Schwegmann once showed me plants from that general area but I never did establish exact origin. What did strike me about the Boesmansrivier plants is the very close resemblance to Haworthia retusa ‘turgida’ when I still considered populations that occur in Table Mountain Sandstone in the Tradouw Pass and north of Riversdale as a discrete species. The only difference to me was the summer flowering time and the resemblance of the flowers to those of H. mirabilis from the Bredasdorp/Napier area. This observed similarity was largely based on a very small sample, colour, and the fact that the flowers were available simultaneously. I must have assumed that this similarity was unlikely to include ‘turgida’. Unfortunately photography was expensive and almost unmanageable for this sort of detail in that era and I had to observe and record from memory.

While I now have only the memory of the turgida-like element in the pass and a myriad of varying populations of H. mirabilis at the northern end and around MacGregor, I have had no evidence of transition to the red-brown plants (eg ‘rubrodentata’) south of the Riviersonderend River from east of Genadendal to at least Lindashof east of Riviersonderend town. This is as the species occurs in putatively Bokkeveld strata.

The Hacklands saw the plants at the top end of the Zig Zag path and the geology here will need a better description than I can give without a geology map. The vegetation is transitional to Fynbos and the stratum an argillaceous one (clayey) not obviously Sandstone nor shale. But the plants are so different. They are smaller than in populations in the area that I know south of the river, fairly bright green and becoming rather yellow in summer stress dress. A physical description of the plants defies description and I would be a loss to refer to the plants as anything but a variable lot. In the amazing context of Latin names in Haworthia I would like to refer to the plants as Haworthia mirabilis ‘hacklandii’ – if it can be forgotten and forgiven (it unfortunately cannot be) that I question the merit and motives for using personal names for taxa. In any case, the serious limitation is to know how to descriptively and sensible circumscribe such a population. The alternative reference is H. mirabilis MBB8040 or H. mirabilis NE Greyton, or H. mirabilis Zig Zag Path. Whatever name is used, this population is in my opinion quite an awesome demonstration of the morphological continuity that I have come to expect in Haworthia. A wide range of comparisons is possible if one takes single clone after clone. I thought ‘sublineata’, ‘mundula’, ‘ turgida’ (from a range of populations) as well as ‘notabilis’ and even ‘elizeae’ and ‘mutica’). The departure from the wider dark green colour of the mirabiloids is the most unexpected feature although this is just what occurs with ‘consanguinea’. This latter is the ground truth and I fully expect that further populations occur to complete a transition to the even more obviously ‘turgidoid’ variant known from deeper in to the Boesmansriver valley. Later driving eastwards and a little further south towards Schuitsberg, we observed very similar habitats 2-3km further north of the road in foothills of the Riviersonderend Mountains.

Among the pictures of the plants is a view from the top of the Zigzag Path looking north into the Boesmansriver valley (or gorge). The hill on the right front seems to be similar to that of the Path and similar low rocky hillsides occur at several places. Significantly there is one immediately north of Riviersonderend where the river passes by on the north side rather than on the south away from the higher hills away from the main range. Kobus has persistently observed that there must be plants there. The evidence of the Zigzag Path occurrence definitely suggests that this must be so and that many more populations exist unrecorded simply because of lack of exploration specifically for Haworthia. While Andy observed the plants at the top of the Path, they are widespread all the way down to the bottom. It is quite amazing that the presence of the plants has not come in to my ken sooner. It is just an observation of mine that Haworthia distribution may be far wider than we suspect simply because Haworthiophiles have not ventured into unlikely areas.

This is a view northward from the top Zigzag Path to the Boesmanspad (Biushmans Route) that runs towards MacGregor 25km to the NE - and to H. mirabilis 'consanguinea'. The weathered cardboard in the foreground is a very sad but loving tribute by children to their grandfather - messages of love and longing painted on two little stones, on the remains of a shrivelled dried wreath.

Flower profiles, faces, and buds

From Greyton we went to Schuitsberg driving further east than previously. This population seems to have led to the speculation that the type of H. mirabilis as illustrated in Botanical Magazine t1354 (1811) could have come from here. In a recent article in Alsterworthia, Gerhard Marx attempts to ridicule my typification of the name ‘mirabilis’. I frankly think this is much more a point scoring effort than a genuine attempt to arrive a taxonomic truth to which Marx claims to aspire. Apart from speculated similarities of some or other clone to that picture, is the fact that this is an old transport route dating to that era. There is a plaque at that site dated 1988 commemorating a 300year history. The problem for me is the variation among the plants that renders the nomenclatural system and the typological approach to naming dismally doubtful. There is just no Haworthia mirabilis var. mirabilis.

Schuitsberg is the origin of H. emelyae var. beukmannii von Poellnitz .I associate that name and description with an exceptional robust, compact and retused version of H. mirabilis (a version with much longer erect leaves with spined margins viz var. rubrodentata {red teeth} was named from further west along the river). I visited Schuitsberg and adjacent farm Nethercourt in the early 1970s. The plants I saw were indeed robust. However I visited there again 2012 and found the place previously visited destroyed and no plants among the many in the adjoining rocky slopes that resembled what I perceived to be ‘beukmanii’. This is repeated in my experience of this second locality on Schuitsberg east (MBB8041) of where I knew the plants. One can refer to the many variants illustrated with this article. Are these all individually or collectively closer to any early illustration on which the name ‘mirabilis’ can be based? It was only a single large very robust plant with leaves nearly 30mm wide and 20mm think that I would have said also agrees with the original acceptance of the “element”. So what can we say here of all these variants? This is a fact of the retusoid species and close relatives. They are simply highly variable with respect to leaf shape, arrangement, markings, armature, and colour, as well as flower characters. The consequence of these is gross aberration of the formal nomenclatural system and whole host of Latin names that are very useful to collectors, commercial nurseries and any other activity where a formal impressive name adds value. What we have at a place like Schuitsberg is that we have plants that can be labelled ‘beukmani’ because they might look ostensibly like the original described plant or its image, or just because it happens to come from Schuitsberg.

Flower profiles, Faces, and Buds.

Regarding the flowers of both localities that I illustrate here, there is again the high variability that I discuss and illustrate in all the preceding parts of Haworthia Update 8. What we now need is a computer wizard who can perhaps explore the possibility of computerised pattern recognition. In this way to look at trying to arrive at a composite single image that captures the identification of a population. It boggles my mind that someone might think, say ‘beukmannii’, is an array of plants scattered through many populations to so constitute a species.

I have tried to approach this whole problematic, provocative, disputatious subject from a rational objective view based on my own education, experience and acquired knowledge to place it in an environment acceptable to formal botany. That environment has not been all that helpful and conducive to a solution either.

Acknowledgement
I would like to thank Dr. Daryl and Mrs. Priscilla Hackland, and Andy Hackland for information and assistance in visiting the Greyton Zigzag Path population. Mr. P.G. Viljoen not only kindly allowed us access to Schuitsberg but took the trouble to drive us there to show us a wider view of the localities and also the commemorative plaque that mark the old travel route. ♦

Haworthia flowers – some comments as a character source, Appendix 7

Posted on May 12, 2012 by Bruce Bayer

Three further records and data for Haworthia mirabilis.

The populations covered here are:

6631 H. mirabilis ‘mundula’, Mierkraal, SW Bredasdorp.
6635 H. mirabilis ‘badia’, NW Napier.
6639 H. mirabilis ‘sublineata’, S Bredasdorp.

There has been some published comment about the distinctiveness of these three populations stating that I do not recognise this because I treat them as variants of single species. The implication is that I do not see any difference. This is quite bizarre. At the present moment I have a digital library of 165 H. mirabilis populations and this is by no means all there are. There is an enormous amount of variation both in and between these populations. If the specified three are to be recognised as species, it means that there is a wholly unrealistic number of species quite out of keeping even with an already highly diverse set of species of the Cape Flora. Furthermore, as I point out in appendix 6, there is no typical variety of H. mirabilis in any practical sense because the variability in the population designated by me, as well as that of Schuitsberg apparently preferred by another, precludes it.

6631 Haworthia mirabilis ‘mundula’, Mierkraal, SW Bredasdorp.
6631 as a variant ‘mundula’ is only known at this one locale. However, similarities can be found elsewhere. The name was introduced by G.G. Smith without any existing recognition of the prior name H. mirabilis and where that may have been applied. Because only illustration exist for which artistic license must be invoked, there is some doubt about just where the original plant may have originated. Frankly I do not think this even matter because the fact of the individual variation that renders the automatic recognition of typical varieties in Haworthia meaningless.

6635 Haworthia mirabilis ‘badia’, NW Napier.
6635 as a variant is generally thought to be only one locale too. It in fact can be seen to be part of a continuum that extends nearly 4km westwards in the same geological stratum. Furthermore it is complemented by quite different variants in at least seven known populations to the north and east. Exploration is by no means complete.

6639 Haworthia mirabilis ‘sublineata’, S Bredasdorp.
6639 as a variant is known immediately south of Bredasdorp, but has been reported further to the southeast in the same stratum. However, there were two populations north of the town no longer extant. Illustrations are available in the literature and herbarium. Based on these, the same illogic that suggest separation of the three specified above would suggest that these are also discrete species. Further populations exist to the near north and northeast of Bredasdorp that intensify and add to the problem of rank. This population, its variation and the statistical difficulties of explaining this variation is discussed in Haworthia Update Vol.4:62-77.

[ed.] flower files names are 6635, but are 6639.

The present appendix represents another set of plant illustrations and also flower photographs. Unfortunately 6631 did not flower very well and only two photographs could be taken. The habitat has changed in the 43 years since I first observed the population. The plant clumps were considerably smaller and there was none of the colour range that I observed in my first visit in 1969 when the plants showed green, yellow and orange.

Observations
The differences in the plants at the three localities are based on three very simple criteria. ‘Badia’ has fewer leaves and no marginal spines, ‘mundula’ has more abbreviated and also numerically more and smaller leaves with a shorter end-area; and ‘sublineata’ has long slender leaves often with prominent venation and larger marginal spines. By these criteria one can nearly always be sure of identification. Nevertheless wider considerations and similarities of one degree or another are so widespread that I consider a stipulated taxonomic distinction impossible and unrealistic. Flower morphology is as variable as the leaf appearances and it is virtually impossible to arrive at a single word or imaged representation of what represents each population. It in fact suggests the restricted view of formal taxonomic recognition that I suggest.

Acknowledgement
I appreciate the co-operation of Mr. E. Conradie of Mierkraal and Mr. P. deKok of Napier for their forbearance. I would be very remiss not to acknowledge the interest in the subject, and input, by Lawrence Loucka who has generated the HaworthiaUpdates.org website and the ISSN 2306-0956 archive for my writings on Haworthia. ♦

Haworthia flowers – some comments as a character source, Appendix 8

Posted on May 12, 2012 by Bruce Bayer

A report on Haworthia mirabilis ‘badia’ / ‘subtuberculata’

I cannot claim that I have resolved the nomenclature niceties around the use of this name and its many varietal names and synonyms. If critically examined even the use of the name “mirabilis” is in doubt and the very original epithet of “Aloe atrovirens” may be nomenclaturally correct. This would create havoc because then the name H. herbacea as typified by W.T. Stearn may best apply. So I put that all aside and use names as I have in my Revision and subsequent publications. I am well aware that there is a problem with the use of H. mirabilis var. mirabilis where it may be thought that the name “mundula” is therefore redundant. I cover all this up with the explanation that there is no typical variety “mirabilis” and actually use just the name H. mirabilis to cover all those populations and variants to which no Latin names exist. I use names like “badia” and “sublineata” as it is generally possible to recognise all or most of the variants from those populations. But names like “magnifica”, “maraisii”, “heidelbergensis”, “rubrodentata”, “beukmannii” and “depauperata” (among others) have no clear and direct application in respect of a population or even a group of variants of any kind. In my Revision I attempt the use of the name “triebneriana” to cover all the variants that are not included under the typical varietal name “mirabilis”. This does not actually work either because the name has its origins at Stormsvlei and there are other populations that are very different from those occurring there too.

My conclusion was, and is, that it is not possible to formally name and describe all the variants in H. mirabilis. Firstly this is true at population level and very much more so in respect of the incredible variation that exists within those populations.

In this appendix I present images of plants and flowers for just two populations…

MBB6987 Haworthia mirabilis ‘badia’. Sandfontein.
MBB7091 H. mirabilis ‘subtuberculata’. Mierkraal, Napier

(Note: – this is not MBB6631 Bredasdorp ‘Mierkraal’ where ‘mundula’. I use now the name ‘subtuberculata’ as one of two generally for that area Northwest of Napier. These are plants with generally erect to suberect leaves, fairly strongly triangulate and tubercled. The von Poellnitz and Triebner names ‘multituberculata’, ‘napierensis’ and ‘turgida’ are also available).

1. MBB6987 Haworthia mirabilis ‘badia’. Sandfontein.

Flower profiles.

Flower faces.

Bud.

2. MBB7091 H. mirabilis ‘subtuberculata’. Mierkraal, Napier

Flower profiles.

Flower faces.

Buds.

The first population is approximately 2.8km west of the “typical badia” population and in almost the same geological stratum and habitat viz. Table Mountain Sandstone with grassy fynbos. The second population is approximately 2.7km northwest of the first and it is on a small ridge of vertically orientated Bokkeveld shale with Renosterveld. There are several populations west and north from here with similar plants. To the east at Napier and north of Napier the plants vary towards smaller and darker versions of H. mirabilis that very loosely indeed have been covered by the name “maraisii”. This is a complete myth and about as accurate as the use of the name “magnifica” to cover all the H. mirabilis variants around Heidelberg and Riversdale. It must be noted that the name “heidelbergensis” is drawn into the arena too and in Appendix 9 I will explain one aspect of the situation with respect to that name.

What this particular report is intended to convey, is the dramatic change related to firstly location, and secondly habitat. I maintain that there is no prescribed species definition in botany and that this is the prime reason for the confusion that exists at every level in botany. Therefore I have arrived at my own view of species as dynamic systems that are not necessarily recognisable in terms of tangible visible characters. There are two important considerations in the way I classify Haworthia. The first is there geographic spatial positions, and secondly the way in which apparent systems relate to each other with respect to those positions. Therefore what I am showing here is that H. mirabilis ‘badia’ is the sandstone version (ecotype) of the species northwest of Napier, and H. mirabilis ‘subtuberculata‘ the shale version a little to the north and then west. H. mirabilis ‘sublineata‘ is a sandstone ecotype south of Bredasdorp and H. mirabilis ‘mundula’ a fairly unique population on tertiary gravel southwest of Bredasdorp. In Appendix 9 I will give an inkling of what happens to H. mirabilis in the shale and tertiary formations north and then west from Napier.

Acknowledgement
Mr. Wynand Wessels kindly accompanied us to the population at Mierkraal. It was difficult to establish just who owns the property at Sandfontein where H. mirabilis occurs and while we met two landowners in the area we were not sure if we were trespassing or not. ♦

Haworthia flowers – some comments as a character source, Appendix 9

Posted on May 12, 2012 by Bruce Bayer

A report on Haworthia mirabilis and Haworthia rossouwii ‘minor’, Rooivlei, NNE Bredasdorp.

In Appendix 8, I explain some of the rationale of my use of names. A detailed report on H. mirabilis can be found in Haworthia Update Vol.3. and in various chapters of the subsequent Updates. It is shown why I consider the possibility that H. mirabilis and H. retusa are in fact the same species.

In this report I will show just one population of many from Napier northwards and westwards for which no broad name exists. There is simply a transformation from elements that I refer to as H. mirabilis ‘subtuberculata’ in Appendix 8, to a very wide range of populations in the central Southern Cape. Both the names “maraisii” and “heidelbergensis” have been applied to populations in this area. The name H. maraisii var. simplicior from Napky may even be relevant but its application, simply irrational.

The populations for which data is presented here are…

7334 H. miriabilis NE Bredasdorp
6638 H. miriabilis Rooivlei
KG36-70 H. miriabilis ‘minor’ Rooivlei
7821 2013 H. mirabilis x rossouwii ‘minor’
7822 H. miriabilis Rooivlei E of Rd
8044 H. miriabilis with H. rossouwii ‘minor’ KG36-70
8045 H. rossouwii ‘minor’ Rooivlei

The population 7334 H. mirabilis is covered in a general way by the name “maraisoid” that simply denotes smaller darker green versions of H. mirabilis. It is not accurate and the terms “floribundoid” and even “heidelbergensoid” are applicable. A complication among many is “hammeroid” for what appears to me as introgression of H. mutica with H. mirabilis. It is just not possible to simplify and summarise the range of populations and variants that lead on from this close to Bredasdorp (and “sublineata”) on to Rooivlei, then north and eastwards to eventually cover “hammeri”, “bobii”, “paradoxa”, “jakubii”, “Windsor”, “magnifica”, “atrofusca”, “toonensis”, “scabra”, “vernalis” and so on ad infinitum. So these pictures together with 7822 just serve as a reference point for what follows.

1. MBB7334 Haworthia mirabilis, NE Bredasdorp

Flower profiles.

Flower faces.

Bud.

It is Rooivlei approximately 26km NE Bredasdorp that concerns me here. It is quite a high-lying area in the wheat growing area of the southwestern Cape. The geology is primarily Bokkeveld shale with inselbergs of later tertiary origins. At Rooivlei the highpoint has tertiary remnants and the Bokkeveld strata include sandstone among the truly clay derived shales. While the vegetation is broadly renosterveld, there is even a remnant of what Acocks’ described as Valley Bushveld. Curiously is the presence of Acrodon quartzicola first described from there as well as Gibbaeum austricola much more widely distributed even to southwest Heidelberg. From the Haworthia aspect, H. marginata is present. It is the presence of a vicariant population of H. retusa ‘turgida’ that is really odd because it is known again about 40km away to the east and in the Breede River river channel.

What is significant is a plant illustrated as no.12 in 6638. I have seen a plant just like this where H. mutica occurs in the immediate vicinity of H. mirabilis at Klipbankskloof about 20km north of Rooivlei. The illustration referred to my well be a hybrid involving H. retusa ‘turgida’. H. mutica is not known closer than Hasiesdrift (Soesriver) about 6km away.

2. MBB6638 Haworthia mirabilis, Rooivlei

Still more significant now is what I refer to formally as H. rossouwii var. minor. This is KG36/70 originally described by me in my Revision of 1999 but as H. heidelbergensis var. minor. I did explain at the time that there were similarities to H. mirabilis var. sublineata. Since then when I did not know all that much, I have explored a great deal and it is clear that the greater picture is that H. heidelbergensis is truly a variant of H. mirabilis. Because the variant ‘minor’ occurs with H. mirablis it forces a rethink. I did this eventually when H. rossouwii was re-discovered at three locations north-northwest and north of Bredasdorp (forcing the abandonment of the name H. serrata) and not very far from Rooivlei. This is really odd in respect of the distribution and variability of Haworthia because I had described H. serrata from near Heidelberg far to the east. I now have records for 12 populations in that area. This distribution brackets that of ‘minor’. My suggestion thus was that it was better a variant of H. rossouwii than H. mirabilis that now included H. heidelbergensis.

3. KG36/70 Haworthia rossouwii var. minor, type locality

KG36-70 looking northwards

KG36-70 habitat viewed from the west.

4. MBB7821 Haworthia mirabilis x rossouwii ‘minor’

Flower profiles.

Flower faces.

Buds.

View looking east of north

A few years ago I revisited Rooivlei to assess the presence of H. marginata there. I did not find it, but instead noted a population 7821 west of KG36/70 that was very unusual and I suspected it had something to do with both H. mirabilis and H. rossouwii ‘minor’. The object of my recent visit to Rooivlei was to examine this a bit more closely with H. mirabilis in flower. I do not have a record for the flowering time of H. rossouwii ‘minor’ but have memorised it as November. In my visit of 12^th Feb. Almost the first plants we found were 2 plants of H. mirabilis (8044) in flower in the immediate vicinity of KG36/70 that was not in flower. The population (7821) west of this is very extensive and the plants extremely variable. They were mostly in flower and there were odd large plants suggesting hybridization with some other species. To the northwest we again found plants (8045) like those at KG36/70 in the same more prominent vertical shale ridges as at the original locality. There was an indication that these plants were not flowering in synchronicity with 7821 and had in fact already flowered. But the plants overall were intensely variable as can be seen from all the illustrations.

5. MBB7822 H. mirabilis Rooivlei, east of Road

6. MBB8044 H. mirabilis with H. rossouwii ‘minor’ KG36-70

Flower profiles.

Flower faces.

Bud.

7. MBB8045 H. rossouwii ‘minor’ Rooivlei NW of type locality

Flower profiles.

Flower faces.

I therefore hypothesize again that what is occurring at Rooivlei was/is introgression of H. rossouwii and H. mirabilis. The area is quite extensive and I have not explored it in its entirety. I would not be surprised if H. rossouwii in its more “typical” form is found there.

Acknowledgement.
I would like to thank Mr Francois Uys for access to Rooivlei. Florent Grenier accompanied us there. Lawrence Loucka kindly and patiently brought some loose ends together.

Haworthia flowers – some comments as a character source, Appendix 10

Posted on May 12, 2012 by Bruce Bayer

Appendix 10 – An additional report on Haworthia mirabilis and Haworthia rossouwii ‘minor’, Rooivlei and Brakkloof, N and, NNE Bredasdorp.

The previous report indicated the necessity for further exploration of Rooivlei. I had observed H. mirabilis, but not reported it in Update 3, at Brakkloof to the west in 2004. So the object of this appendix is to remedy this oversight and to also cover more area of Rooivlei. At Brakkloof there are several small remnants of rocky shale and we located several populations, while at Rooivlei we actually explored the very western boundary. This constitutes the same topographical area as the Rooivlei populations but the plants we observed were factually on Brakkloof.

The populations reported on here are:-

6537 H. mirabilis, Groudini, W Napier
7285 H. mirabilis, Brakkloof 3
8046 H. mirabilis, Brakkloof 2
8047 H. mirabilis, Brakkloof 1
8048 H. mirabilis, W Rooivlei 1
8049 H. mirabilis, W Rooivlei 2
8050 H. mirabilis, W Rooivlei 3
8051 H. mirabilis, E Rooivlei
8045+ H. rossouwii ‘minor’, NW type locality
8052 H. mirabilis, S.Welgegund
8053 H. mirabilis, Welgegund SE 8052

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Very brief note re Haworthia nortieri flowers

Posted on May 24, 2012 by Bruce Bayer

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.

While I have written an account of flower appearances in a small selection of populations, I also came across these few images I have of flowers in what I regard as the species H. nortieri. I have also added images of a single flower of H. maculata from a population high in the mountains at Worcester that could be seen as a southern extension of the H. nortieri set of populations. Note must be taken of my early contention that H. nortieri and H. globosiflora were the same species, based on my observation of the intermediate appearance of the flowers of a Vanrhyns Pass population. The H. maculata bud is typical of the species in the Southern Cape, whereas H. nortieri has rounded bud-tips.

The flower of the Trawal plant are dramatically different from that of, say, Sneeuberg. It is very understandable that differences like this lie at the base of all the argumentation and confusion that so despoils the naming and identification of Haworthia. A classification has been needed against which to explore and examine these differences. It seems to me totally unnecessary to try and construct another hierarchy of solely Latin names while so little is still unknown. ♦

♦

A sequel … Still another view of Haworthia retusa and Haworthia mirabilis

Posted on July 7, 2012 by Bruce Bayer

It has long been my contention that there is no separation between Haworthia retusa and Haworthia turgida. It is one very variable system viz H. retusa, with a larger fairly non-proliferous plants tending to level areas and then smaller proliferous plants on steeper habitats. There is huge variability among members of any one population and of course much more between populations. Over and above this is the relationship of this apparently one single system, with H. mirabilis that is probably even more complex and varied. If one takes all the known populations and variants into consideration it become necessary to ask if H. retusa and H. mirabilis are also not just elements of one system, and one species. If all the considerations are summed and referral is made to vegetation and speciation drivers; what constitutes an area of endemism, then I am sure the answer will be “Yes”! What seems to have happened is a natural sequence. As sampling has progressed so has there been recognition of differences. The logical outcome is that sampling progression should lead to understanding and synthesis by reduction. Unfortunately there will be diehards that stay with the differences syndrome and cannot see the similarities.

There is surely no longer any doubt that Haworthia classification has been confounded. There are several factors. One is the historical one of sampling and naming. Sampling dates from the seventeenth century and description based on a few words and weak illustration. The second problem has been a nomenclatural system that revolves around the single types and assumes that departures from that still allow comfortable accommodation of all other departures (variants) under the primary name. The third problem is the absence of a species definition deriving from a lack of knowledge and hence understanding of what species are. The fourth problem is enthusiasts, writers, collectors, editors, reader etc. who generate and propagate within the confines of their own needs, limitations, knowledge and understanding. Too often they are not adequately informed to undertake something that really should be the task of professional botanists. Of course it is also true that professionals have not proved to be faultless either, as simply the lack of a species definition alone indicates.

From my personal point of view, I consider the sampling history and the nomenclatural constrictions of priority and automatic creation of type elements, among the main obstacles to a classification solution. Perhaps it is only secondary to the human factor where writers become anxious to establish their own opinions, based on who knows what, crowing from the top of a metaphorical farm dungheap. I have paid a lot of attention to an element that I name as H. retusa ‘nigra’. It is based on a very unrepresentative specimen from Kransriviermond where it seems as if it is a product of hybridization between H. retusa and H. mirabilis. But this situation, and the name, is inextricably involved in a series of populations grouped in areas like Van Reenens Crest (Swellendam), Klip River (W Heidelberg) and Kiewietsvlakte (W Riversdale). These populations do not seem to figure in any earlier exploration and if looked at objectively may now perhaps be seen as the mother lode from which H. retusa, H. mirabilis, H. pygmaea, H. mutica and even H. emelyae as species may emerge. The reality is that all these may not in fact even be discrete species.

In the forerunning article I discussed some new populations at Kruisrivier northeast of Riversdale and where they occur along the Kruis River. This river partially follows the interface of the Cape Sandstone Fold Mountains in an east/west direction and the situation is replicated to some measure elsewhere between Worcester and George. Most relevant is the similarity of the Kruis River valley and its south banks to the situation along the Klipriver west of Heidelberg. But it is not in the scope of this discussion to cover that now and I would in any case need to research the geology of both areas to do so. I will just present images to cover firstly the area, then to allow creation of a composite image of what the small sandstone H. retusa looks like, then images from just two populations of H. retusa to show how shadowy our image of this species is; and then I will show the images of plants from five points down a distance of about 4km along the south bank of the Kruis River to a point south and west of the better known Kruisrivier plants.

Setting the scene.
The Kruis River Valley is slightly east of north from Riversdale and the Kruis River is a headwater of the Goukou River that enters the sea at Stilbay. The views I have (figs. 1-4) are of a satellite image of the Valley from where the Kruis River exits the Langeberg Range to where it joins the Goukou. Three images are from the south bank looking northwest and northeast. The area is very heavily impacted by alien vegetation. The grazing animals are mainly cattle (beed and dairy) and hoof impact on the slopes is severe. The underlying shale along the south bank is not exposed and there is both boulder deposit, river alluvium and even some marine terrace in evidence. Nevertheless the area is not so dramatically varied geologically as is the area around Heidelberg to the west. Hence the transitions and interactions between species and their variants are both similar but very different. The initial conditions will be very different too.

Fig. 1 An overview of the Kruis River Valley.

Fig. 2 Some indication of the topography of the south bank.

Fig. 3 View northwest from a central position.

Fig. 4 View to the northwest across the flood plain.

The populations.
The first three sets are to briefly review H. retusa. The general perception of H. retusa is very restrictive and similarly the case with what was H. turgida. I consider them together. Nevertheless I have to sympathize with the splitter approach because I have to make a concession for the sake of discussion. Thus…

Set 1 MBB7895 H. retusa ‘caespitosa’, Diepkloof, Heidelberg (figs 5-9).
I explored the upper Kruis River in early 1970 and found the small sandstone version of what was then recognised as H. caespitosa. Later seen as H. turgida, it is known at many places from the Tradouw Pass, north of Heidelberg, Garcia Pass and Kok’s peak. Small and very proliferous, its leaves are also quite spinose on margins and keel and also flecked with reticulate and longitudinal translucence. The summer coloration tends to reds and yellows. I do not have images of this actual form but show five from a population south of Heidelberg that is very similar. But it should not be assumed that the transitional flow in the Heideberg area equates that at Kruis River. The variants down the length of the Klip and Duiwenhoks Rivers is another profound story.

Set 2 MBB7758 H. retusa, Skietbaan, S Riversdale (figs 10-19 ).
I show images of this species very recently taken. This is because I do not think that as a species H. retusa is properly appreciated for all its variants. It is this reality that we are confronted with when considering populations as at Komserante and now Kruisrivier where there is an evidence that it cannot any longer be seen as completely removed from H. mirabilis.

If images 10a and b appear to be different from the rest of this wet, they should. They are plants from the same locality but they were taken 4 years ago when most of the plants were very much larger. They illustrate a very useful point – the plants do NOT necessarily look the same all of the time.

Set 3 MBB8010 H. retusa, 8km S Riversdale (figs 20-28 ).
Primarily one should consider surface roughness and colouration as main separators from H. mirabilis. Flowering time is the prime differentiator and this is what is now to be seen in another light.

Set 4 MBB8004 H. retusa↔mirabilis, Bloekombos, Kruisriver (figs 29-42).
Reference can perhaps be made to the three sets illustrated in the preceding article. Here is will just re-capitulate to say that there is some doubt in respect of plant appearance and colouration, to examine the view that the represent H. retusa or H. mirabilis. (I dismiss totally and absolutely the notion that a third species needs to be fabricated to accommodate differences impossible to itemize or catalogue across the range of variants within and between populations.) I do not think that the similarity of surface roughness to that of the H. mirabilis ‘atrofuscoids’ should be overlooked – even some of the leaves show the tendency to roundness at the ends. This particular population was in full flower at the end of July.

Subset 4 The flowers (figs 43-45). I do not see anything to distinguish these flowers from those photographed for the Wegwysersrivier population and given in the preceding article. It is difficult to imagine that the flowers may offer any distinctive features in the direction of difference that are not already offered by vegetative and geographic considerations. There may of course be direction towards similarity.

Set 4 H. retusa-mirabilis, MBB 8004 Bloekombos, Kruisriver – Subset 4a Flower profiles

Set 4 H. retusa-mirabilis, MBB8004 Bloekombos, Kruisriver – 45. Subset 4b Flower faces

Set 4 H. retusa-mirabilis, MBB8004 Bloekombos, Kruisriver – 45. Subset 4c

Set 5 MBB8003 H. retusa↔mirabilis, W Bloekombos, Kruisriver (figs 46-73).
Curiously this population was only in early bud although only a few hundred meters away from the preceding. I do think there is significant difference in the appearances of the plants with more translucence of narrower leaves. However, plants from this and the preceding population could very easily be said to identify with those in any of the H. mirabilis populations southeast, south and west of Riversdale. It is also obvious that there is a degree of similarity to the rougher plants of H. retusa illustrated in sets 2 and 3, and also to the Komserante H. retusa↔mirabilis plants.

Set 6 MBB8007 H. retusa↔mirabilis, 600m W Bloekombos, Kruisriver (figs 74-81).
The banks west of set 5 are less steep and the terrain not clearly differentiated into discrete habitats. Heavy cattle trampling would severely impact on plants. Nevertheless we did find a small colony and are confident more would be found if more time was spent searching. The area is quite extensive and we did not consider several north/south valleys that could well harbor plants. The same is true for quite large hinterland to the Kruis River Valley and Etwin Aslander’s plants, similar to the ones we saw, are surely present back there. This small colony reflects further transition to H. retusa ‘turgida’. The leaves are smoother and more translucent. There are some floral differences muted by the small sample and by the fact that these features such as the absence of frilled base to the bract and the presence of a short pedicel, are variations observed within populations elsewhere.

Set 7 MBB8008 H. retusa↔mirabilis, 1km W Bloekombos, Kruisriver (figs 82-83).
Also barely, registering as a population, these odd plants support the predicted presence of a direct transition from the Kruisriver mirabiloid-like H. retusa to the known sandstone forms of H. retusa ‘turgida’. Hoof action has severely impacted this area and it sems very probable that there was a larger population at some time or another. The slope militates against the solitary ground-level growth form of the more usual H. retusa but not steep or rocky enough to be home to the turgidoid cliff growing forms.

Set 8 MBB8005 H. retusa ‘turgida’, S Wegwysersrivier (figs 84-98).
The use of the equilibrium sign for the preceding is more informative than accurate. It reflects the problem of decision making where it is not clear if H. mirabilis is even in the area. This of course impacts on the situation further east when the reality of H. pygmaea and all its associated variants are brought into the picture. I am sure it is inarguable that we are now confronted with plants that are truly similar to H. retusa ‘turgida’. Curiously the flower is much the same as in MBB8003 and 8004 to the east but there is a difference in that the peduncles were softer and shorter than of plants to the east and suggesting the shorter lax habit of the cliff dwellers. The habitat is unlike the preceding in that the Tertiary deposit is more alluvial and the rock is more boulder-like. Trampling is still a severe problem. Note the two pictures of a H. retusaXfloribunda hybrid.

Set 9 MBB8006 H. floribunda, S Wegwysersrivier (figs 99-107).
The presence of this species is no surprise. It was quite abundant although slightly separated from where we found the H. retusa ‘turgida’. It depends on rocks for protection from trampling. This species of course generally flowers in late summer but once again here is a hybrid present with the other parent flowering a good 6 months later. This has been observed in several other places where these same two species occur in close association. [photo file names are mistakenly named MBB8005, they are in fact MBB8006 – ed.]

Conclusion
The product of this exploration was based on prediction and I would wish that cognizance was taken of the fact that this could and can be done. Using an aggregate or group category and a host of Latin binomials is not botany and obfuscates things. Perhaps to the benefit of traders, but certainly confusing to the collector who make wish to know more about plants than simply having a label.

Acknowledgement
I have already acknowledged the help of Wilhelm and Mandi Zietsman; and Gert and Lynette van Rensburg. We were now also assisted by Wessie Wessels, a retired airline pilot who owns the Bloekomsbos Farm. Kobus Venter came to see my pictures and I really value his interest and useful comment. I wish there was more similar interested and informed comment. ♦

A further report on Haworthia mirabilis in the Greyton area.

Posted on July 7, 2012 by Bruce Bayer

Appendix 11 to Haworthia Update Vol. 8.

In appendix 6 I reported on H. mirabilis just east of Greyton and also at Schuitsberg further east and south. I undertook this excursion to fill out on a population at Uitkyk MBB7092 west of Genadendal illustrated with one image in Haworthia Revisited. En route we discovered still another population along a road from Caledon to the northwest (8055 Hammanskraal), briefly called at a site east of the bridge on that road crossing the Riviersonderend (MBB8056). We also visited the population MBB8040 east of Greyton and explored some of the hiking trail between Greyton and McGregor.

The population 7092, H. mirabilis, at Uitkyk, is indeed interesting. It is a steep riverside, south facing, vertical slope. There are many plants that may not receive any direct sunshine for most of the summer and of course none in winter. It is really curious because there are groups of plants that seem to be holding clumps of moss, lichen and a modicum of soil to the rock. There are orchids, oxalis, shade-loving Asparagus, and all the small bulbs one expects in these moist south facing habitats. The rock seems to be metamorphosed from fault-shearing heat and pressure on shale. Among the illustrations is a view looking east along the road with the roadside south-facing habitat on the left. The Riviersonderend River is immediately on the right. In the distance ahead is Leeukop, the type locality for H. mirabilis ‘rubrodentata’. That is a dry north-facing slope.

The 8055 Hammanskraal population is about 5km due south of Leeukop and is quite new to me. We were attracted in passing to a very promising looking northwest facing shale ridge and were not surprised to find plants there. However, it does consolidate the western limits of the species. A paradox is that here the plants seem to be only in little pockets of soil in the shale ridges. There are none in the more friable and developed soil between the exposed unweathered shale. The plants were in seed and there were still a few flowers indicative of a flowering time a good two months behind populations to the north and east. The plant 8055.17 could very easily be mistaken for similar clones in populations northwest of Napier (‘subtuberculata’).

8056 is a population that Kobus Venter drew my attention to. We only looked along the road and did not spend much time there. This is similar habitat to Leeukop where the var. rubrodentata originated. That original description and name is associated with a variant with relatively long narrow leaves with well developed and very red spination. Of course the colour is associated with the northern aspect. Red spination is quite common elsewhere in H. mirabilis and is evident on the 8055 plants too. I include a view of a nearby site as evidence of road building vandalism. For some reason or other the road builders seem to have thought it necessary to scrape and ravage a wide strip of countryside between where the road eventually was established and a wonderful riverside steep slope full of Aloe glauca. It is really curious that there are several aloe populations like this at the H. mirabilis sites, but the two species seem to be exclusive with the Haworthia on the lightly less weathered and more sparsely vegetated area.

We called at the population 8040 east of Greyton because I wanted to obtain a sample to see if the colour was maintained in cultivation. I include a picture 8040.9 to show the offset which has no tubercles, spots, or spines on the underside of the leaves so commonly associated with H. mirabilis. I said of the var consanguinea (southwest of McGregor) that plants could be mistaken for H. mirabilis ‘notabilis’ from Robertson. It is true of this clone too.

The last thing we did was explore the start of the 15km Boesmansrivier hiking trail from Greyton to McGregor. It is along a traverse through the Riviersonderend Mountains. The Grobos River originates deep in the mountain about 5km southwest of McGregor and runs in a deep gorge toward Greyton. From Greyton the hiking trail voids the deep river valley and ascends a high ridge running parallel to the south of the river. Then there is a second deep valley again south of that. So the path is along the top of a high ridge from where it eventually does drop to a waterfall on the river. We never got that far but I assume the trail then follows the river and then climbs out again at the north eastern end. There were no accessible and likely habitats along the first portion of the trail. We did explore very promising looking habitat south of the trail start, but found nothing. This is curious because it is only about 1km north of the ZigZag path where the plants are abundant. Of course we know that plants occur along the trail northeast of the waterfall and had hoped to chance on suitable accessible habitat on the way there. I have included some pictures of the scenery to show how steep and rugged the terrain is. It is almost certain that there are more populations in the area. Given the adaptation to the Uitkyk habitat contrasted with both Leeukop and Hammanskraal one cannot rule out any possibility of more populations in these mountains. I include a photograph looking southwestwards to show the territory with populations known on those distant ridges both in the extreme west and again extreme east. Plants have been reported in the higher areas. There are also low mountains to the west behind and west of Leeukop unexplored. Hammanskraal would be discernible in the picture in the distance to the far right.

View 2 looking northeast from within hiking trail — View 1 over Greyton from the northeast

Acknowledgement
Mr. Willie Smal for access to Hammanskraal. My son Warwick for transporting and accompanying us. Kobus Venter for alerting me to the plants east of Leeukop. ♦

Comprehension and significance

Posted on October 21, 2012 by Bruce Bayer

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.

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 one 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 minima and pumila flowers

Posted on January 18, 2013 by Bruce Bayer

This H. pumila flower is apparently persistently regarded by botanists as actinomorphic (star-shaped, radially symmetrical) – as though zygomorphy (yoke shaped, bilateral, asymmetrical) 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

Haworthia minima

♦

MBB7989 Haworthia pumila, Lemoenpoort

Posted on January 18, 2013 by Bruce Bayer

Kobus drew my attention to a glabrous plant of Haworthia 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.

Flower profiles

Flower faces

♦

14. Flowers

Posted on July 19, 2019 by Bruce Bayer

42. A very critical bit of information is missing in Haworthia classification. This is flower information, which has been traditionally scorned as not informative. Possibly the reason it tells what no one wants to hear. Here are flower profiles for these two imponderable mirabilis (MBB80568) and floribunda (MBB8059) populations from W Swellendam. What do you think?

8058a flower faces (H. mirabilis)

8059 flower faces (H. floribunda)

8058b flower profiles (H. mirabilis)

8059 flower profiles (H. floribunda)

Lawrence Loucka: At a quick glance I can tell these are Haworthia flowers. On closer review it seems the two sets are slightly different, but I don’t have the vocabulary to describe them. The base of the flower tubes, the perigon, seem similar, and the petal center colors range from yellow/green to red/brown in both sets. 8058 top 3 petals seem less spread in face view than 8059. Bottom petals of 8059 seem more curved in profile view than 8058. But if I mixed all the images up I’m not sure I could sort them out.

Bruce Bayer: Yes Lawrence – that is the real rub. I also have sets of pictures of the changes of flowers with age as a complication. My pictures were taken to avoid that. But I also thought that if I halved each set it would also be near impossible to match the halves up again. In Updates I discuss the variables and explain that some of the differences are greater than that on which species are based, e.g. pedicellate vs stipitate, bracts stem-wrapping vs recaulescent, etc.

Bob Guffanti: All other plants are sorted based on floral details, with a little DNA evidence thrown in, and a nod to foliage.

Bruce Bayer: Yes Bob. It is very funny and ironic that the floral differences that distinguish the three “Haworthia genera”, was ignored and that DNA evidence was needed to recognise them. Similarly funny and ironic is that flower similarities are ignored because the foliage are slightly different.

also see …

♦

Flowering Time Redux

Posted on March 5, 2023 by Bruce Bayer

Two very smart blokes who are a lot more competent than me. They know who they are. One of them asked the question about flowering time and all that in relation to speciation and the obvious implication for recognition of species. No I have dealt with that in detail throughout the Updates. We have the problem of retusa (nomenclaturally correct but phylogenetically, if there is such a thing, wrong) and mirabilis (technically, and even perhaps nomenclaturally a later name for atrovirens). The same conundrum crops up in Tulista – are there four species or is it one system. Opalina comes to mind because it flowers November (or it did for me) but I observed without anything to substantiate what I say, a putative hybrid marginataXpumila did (it is extinct now due to its place on the verge of a National highway through Swellendam. Marginata near Swellendam flowers wrongly in Nov. too. The flowers were also identical while a bigger, and whiter than is normal for T. minima. Just who is the taxonomic lunatic that made the change from my Tulista minima to T. minor or even H. minima to H. minor? This is total conflation of purpose. Marginata and pumila should flower in Jan/Feb. There are anomalous populations at Ashton that “we” dismiss as hybrids of those two species, with adjacent plants undoubtedly the same as the two species “we“ insist on. If they can hybridise like this, we have to ask how could it possibly have happened. I have other records and even published pictures and comments about this hybrid conundrum. It is dramatic in Tylecodon aborescens, Tylocodon cacallioides and T. wallichii where I have grown the arborescensXcacaliodes from seed to find it fully fertile. This picture shows an inflorescence of Haworthia pumila (some authorities recognise it as Tulista pumila and attempted to demand the name Haworthia major to confound us all. I unkindly point to these as idiots that totally conflate the issue of a name system that serves people, and one that serves egocentricity and intellectualism). Not that there is flower, and ripe capsules on the same inflorescence. Does this have any significance? It touches on another problem. This is of how seed ripening time relates to conditions for germination events and indeed it needs special conditions for seed to germinate and establish. A vast subject. Of nurse plants, allopathy and inter-species plant communication? Of my paper cabbages and kings. (to music). ♦

Haworthia Updates

Thoughts and observations on Haworthia

Category Archives: Flowers

Volume 3, Chapter 2:- Flowers of some Haworthia

Volume 3, Chapter 13:- Haworthia IS confusing

Haworthia limifolia – a conundrum or a lesson?

Haworthia flowers – some comments as a character source, part 1

Haworthia flowers – some comments as a character source, part 2

Haworthia flowers – some comments as a character source, part 3

Haworthia flowers – some comments as a character source, Appendix 5

Haworthia flowers – some comments as a character source, Appendix 6

Haworthia flowers – some comments as a character source, Appendix 7

Haworthia flowers – some comments as a character source, Appendix 8

Haworthia flowers – some comments as a character source, Appendix 9

Haworthia flowers – some comments as a character source, Appendix 10

Very brief note re Haworthia nortieri flowers

A sequel … Still another view of Haworthia retusa and Haworthia mirabilis

A further report on Haworthia mirabilis in the Greyton area.

Comprehension and significance

Haworthia minima and pumila flowers

MBB7989 Haworthia pumila, Lemoenpoort

14. Flowers

Flowering Time Redux