Haworthia Revisited – 27. Haworthia parksiana

27. Haworthia parksiana V.Poelln., Cactus J 5:34(1936). ibid., Feddes Repert.Spec.Nov. 41:205(1937). ibid. 43:104(1938). ibid., Desert.Pl.Life 10:48(1938).  Bayer :143 (1976).  Bayer :50 (1982).  Scott :121 (1985).  Type: Cape, Great Brak River, Mrs Helm in PE Parks 636/32. Not preserved. Lectotype (B&M). icon (B).

parksiana: in honour of ‘Mrs Parks’.

Rosette stemless, proliferous, 3-4cm φ.  Leaves 25-35, 1,5-3cm long, blackish-green, sharply recurved, minutely tubercled, tip barely pointed.  Inflorescence simple, slender, to 20cm.  Flowers few, narrow, whitish with dull greenish venation.

1982 – H. parksiana acquired its name in a very odd fashion. Von Poellnitz received the plants from F.R. Long under a Port Elizabeth Parks and Recreation Department collecting number ‘Parks 636/32’.  Long had in turn received the plants from Mrs Helm of Great Brak.  Von Poellnitz in error attributed the collection to a ‘Mrs Parks’ and hence the name.  It is a very distinctive and very small dark species occurring very locally in Mossel Bay and the Great Brak area.  Rather than having the flattened retused end area of the typical ‘retused’ species, the leaves are recurved at the ends.  The flower buds are also round‑tipped at the end.  The most obvious relationship that H. parksiana has with other species is with H. floribunda, although these two species are separated by the Gouritz River valley.  H. parksiana, apart from being the smallest species, is also possibly the rarest and occurs only in very small numbers in the wild.  It grows completely under the protection of small karroid shrubs, well hidden in the fallen leaf debris or among moss and lichen.  The Mossel Bay area receives rain throughout the year but H. parksiana is particular about not having too much water.  Offsetting does occur but growth is very slow.

1999 – The species is known to me from 3 localities.  One of these is within the township of Great Brak, the other is on a rocky spur jutting out into a district road, and the third is on the very edge of a wheat field.  Its continued existence thus seems to be fairly precarious.  The relationship is with H. floribunda which is known (in terms of its probable or possible relation to H. chloracantha) at its most eastward, north of Albertinia.  That population apparently includes forms which are comparable with H. parksiana.  J.D. Venter cites the case where he has grown field collected seed of H. magnifica from south of Riversdale and observed parksiana-like plants among the offspring.  This is what should be expected in terms of the reciprocity of forms, and also in terms of a ‘chaos’-driven speciation theory.  Otherwise the species is readily recognisable and a relief from the contorted synonymies of other species.

Distribution: 3422 (Mossel Bay): Dumbie Dykes (-AA), Bayer 157 (NBG); Great Brak (-AA), James in NBG8106/45 (BOL), de Wildt (BOL), Smith 2936 (NBG); Botteliersberg (-AA), Bayer (NBG).

Volume 5, Chapter 17:- New populations of Haworthia chloracantha, Haworthia parksiana and Haworthia kingiana

In Chapter 1 of  Haworthia Update Vol. 2, I discussed H. chloracantha and H. parksiana in the context of H. floribunda. Fig. 8 in that publication is labelled “North of Herbertsdale” when in fact it is MBB7425 from the Wolwedans Dam north of Great Brak (see fig.1). This was deliberate and not seriously misleading as the plants from the two respective populations are virtually identical. The correct images for that “north of Herbertsdale” are in Haworthia Revisited and labelled JDV87/80 and 97/138.

Recently I had an opportunity to visit Herbertsdale in connection with chameleons and took the opportunity to visit a locality also north of Herbertsdale, but a lot closer (see Figs 2.1-2.11. MBB 7825) reported to me by Mr. Jaap Viljoen of Swellendam.

The plants there are smaller and much less clump-forming than JDV87/80=97/138 and are more reminiscent of H. parksiana. Unlike JDV97/136 (see figs. 3) that are solitary, small, dark-green plants growing in the lichen on a steep east-facing conglomerate slope, the plants are quite green in colour and often the tips of the leaves are slightly rounded and flattened as in H. floribunda. The habitat is west-facing on an old gravel river terrace and much drier and warmer than for JDV97/136, in sharp contrast to the very steep north-facing clay cliff where KDV87/80=97/138 occurs. In neither of these latter two sites are other plants significant, while at MBB7825 the plants are under renosterbush (Elytropappus) and related vegetation. I should mention that my wife on seeing the plants commented on the similarity to H. parksiana and this is not an observation that can simply be dismissed.

About 3km south of Herbertsdale (see fig. 4, MBB7827) we again found very similar plants, perhaps a little more spinose and slightly more clump forming. Neither of these two new populations fit comfortably in the existing formal varieties, as indeed is true for so many populations in most of the other species. I do not think it is rational to attempt formalizing names for them as there is quite substantial variation in each population. Others may do so if these plants ever get into general cultivation from vegetative propagation and onto lists.

From Herbertsdale we went to Klein Brak to investigate a set of four populations on the farm Rooiheuwel as indicated to me by Gerhard Marx. One of the species supposedly there was H. pygmaea and it was rather distressing to find that the Water Affairs Department has seen fit to run a bulldozer over the area  with no indication that there was any need for doing so. However, we did find the other three species indicated by Gerhard. One is H. kingiana (see figs. 5.1-5.4 MBB7835).

The others were H. parksiana (see figs 6 MBB7828)

and H. chloracantha (see Figs 7 MBB7829), but this requires a little bending of the truth.

This H. parksiana site is about 400m southeast of an old locality of mine on an outcrop of rock virtually jutting into the road and now largely obliterated. At Gerhard’s site (viz MBB7828) the plants are small and while there is little doubt that they are generally alike to H. parksiana, there is definitely some degree of hybridization and some of the plants may actually be H. chloracantha. This is a rather difficult decision to make on the basis of stressed plants in habitat. This habitat is very restricted to a patch of fairly level aggregated conglomerate so that the plants are virtually in tiny shallow soil and lichen encrusted patches. A little distance further north there is another population to which we assign the name H. chloracantha. This is above a steep loose conglomerate cliff with a little more soil and immediate bush. The plants have rather abbreviated leaves and a darkish colour. There must be some doubt that they are discretely H. chloracantha. The habitat is not so restricted and one is compelled to ask why the plants then so are.

I try to avoid the unanswerable question of how these two species that flower together and seem to be able to hybridize quite freely, maintain their identity and come to occupy such specific, localized and widely separated sites? It would be nice to think that the technology is now seemingly available in DNA sequencing to begin probing these questions, and I will point, with reference to chameleons (see next chapter), to what I think is a disturbing reliance on that technology without the necessary knowledge and experience of what actually can be seen in the field. ♦

43. Albertinia 7

122. 2020.04.07 – Like with the present pandemic we are coming to something difficult to comprehend. I went to Botlierskop, Rooiheuwel farm, north of Klein Brakrivier hoping to see a slender long-leaved form of Haworthia chloracantha (a JDV record). Instead I came across this population of rather stubby plants. Keep this population in view – two close populations to follow and then an issue of proximities!

Also on a rock slab about 70 meters away. Is this still chloracantha or is it parksiana?

Frantisek Vesely – We saw the similar situation – on slope there was chloracantha (+ hybrids), on flat a few dozens meters away there was parksiana and its hybrids with chloracantha – not difficult to recognize what happened there as they were so close and mixed up but on one spot most of them were chloracantha-like and the other spot were more parksiana-like plants.

600M away there is a population of uniform parksiana. But how can we say hybrids for the previous? How long have these populations been in existence? Is transfer of pollen a problem and over what distance? There seem to me to be a host of unanswerable questions in general about hybridization as an explanation for variability. It is linked to the more general question of co-occurrence – of mixing or non-mixing of species. Ring clines? Also something we should really try to document – i.e. the proximity of the various species to one another. Add to that the occurrence of hybrids.

123. 2020.04.09 – This population, east of Riversdale, is an aspect that really calls for attention – proximity of kinds (species) and hybridization. At this locality there is H. retusa and H. floribunda in contiguous/adjunct/closely neighbouring populations. Among the floribundas there is a single putative hybrid? How often does this happen and why are kinds (species) so seldom growing together? When is an entire population comprised of hybrids? What comes in between? Let me just add that I see very little in the taxonomic literature dealing with the problems of variability that exist in many genera other than Haworthia. It is simply obscured.

I am quite aware that my comments are often cryptic and often deliberately so. As a society we are very misled and never more so than in respect of the present pandemic. I do not see how we can put that aside and think that we can at the same time depend on our collective intelligence to solve and understand anything else e.g. taxonomy of Haworthia. It is a conscious creation and that consciousness has to be lifted to a level that we see things for what they really are. Hybridity is at the root of species definition and as such a critical step to recognising species. At the same time geographical location is also critical. To to think anything can be explained while there is a paranoia about revealing it, is wishful thinking.

2020.04.12 – There is a problem with classification where priority creates difficulty. The name Haworthia retusa has nomenclatural priority over the name turgida, when in actual fact the turgida form is the main one and retusa is a variant of that. It is much easier to then understand, describe and explain the idea that retusa becomes mutica in the west, retusa and mirabilis become pygmaea in the east, while turgida and mirabilis become emelyae in the Karoo. That might be where I should now leave things. There are a hoard of complexities that just get lost in the needs and activities of the majority who have no need of much more than a lot of desiderata. ♦