I wrote a short note for Haworthiad, to explain a picture of Breuer’s new species H. fusca (MBB7507), and said “… the fact is that it is from a small population just west of Albertinia en route to another of Hayashi’s (?) species H. esterhuyzeniae, and also to Breuer’s H. vincentii. As readers we are being conditioned to accept that there are many kinds of species such as biological species, morphological species, taxonomic species, good species, bad species etc etc. so a latin binomial could mean anything (and the word ‘tautology’ has been added to my vocabulary). Botany needs a sensible and practical handle to a squadron of populations from between Albertinia and Great Brak. I would gladly supply this if somehow I could be assured that the act was not seen to be the clown’s contribution to the circus.”
Without any assurance, but with the encouragement of Stirling Baker, I am going to try and produce an explanation.
Put very bluntly and without any apology to a group of people who definitely deserve better, my life experience is that taxonomy is largely a farce despite the fact that it works surprisingly and exceedingly well. I have already written around the subject a number of times and do not want to repeat what is not necessarily true other than the contribution these thoughts have made to my personal psyche.
In this contribution I am discuss, illustrate and then propose that there are just two species, H. retusa and H. pygmaea in a complex where presently more than nine species and varietal names are being used. I do this in consideration of all the populations of Haworthia known to me in the winter rainfall biome. Thus I recognize the need to rationalize species like H. mirabilis (which will then absorb H. maraisii, H. magnifica and H., heidelbergensis, and H. retusa (which will absorb H. turgida. There is a major problem in that the populations indicate three species in the west, viz. H. mirabilis, H. retusa and H. mutica but these appear to fuse or morph to two in the east. My past treatment of species and varieties like maraisii, magnifica, acuminata, dekenahii, argenteo-maculosa will bear witness to the nature of the (my) problem.