Category Archives: Update 8

Haworthia Updates Vol. 8 – Table of Contents

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

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Haworthia flowers – some comments as a character source.

M B Bayer, PO Box 960, Kuilsriver 7579, 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.

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

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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.

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

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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.

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

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Appendix 5.

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. = 10cents 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.

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

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Appendix  6  to Haworthia Update Vol 8.

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.

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

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Appendix  7 to Haworthia Update Vol 8.

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.

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

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Appendix 8 to Vol. 8 Haworthia Update. 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.

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

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Appendix 9 to Vol. 8 Haworthia Update –  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.

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

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Appendix 10 to Vol. 8 Haworthia Update – 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:-

  1. 6537 H. mirabilis, Groudini, W Napier
  2. 7285 H. mirabilis, Brakkloof 3
  3. 8046 H. mirabilis, Brakkloof 2
  4. 8047 H. mirabilis, Brakkloof 1
  5. 8048 H. mirabilis, W Rooivlei 1
  6. 8049 H. mirabilis, W Rooivlei 2
  7. 8050 H. mirabilis, W Rooivlei 3
  8. 8051 H. mirabilis, E Rooivlei
  9. 8045+ H. rossouwii ‘minor’, NW type locality
  10. 8052 H. mirabilis, S.Welgegund
  11. 8053 H. mirabilis, Welgegund SE 8052

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A further report on Haworthia mirabilis in the Greyton area.

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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.

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