Alooideae Asphodelaceae And The Genera Thereof by M Bruce Bayer Reprinted from Alsterworthia International Special Issue No 4 My fascination with Haworthia has presented me with many problems in the way the genera in the Alooideae have been discussed appraised and modified in and subsequent to G D Rowley s analysis 1967 Parr 1971 coalesced Astroloba Haworthia and Poellnitzia and I refuted this in 1972 when I also wrote a rebuttal of Rowley s paper My remarks did not deter Mrs ObermeyerMauve 1973 following and accepting Parr nor in adding Chortolirion to Haworthia Rowley 1976 quite pragmatically discussed the Aloid genera but in 1980 suggested the incorporation of Poellnitzia in Aloe He implemented this proposal in 1981 and promoted it again in 1985 Smith and van Wyk 1991 published a cladistic analysis of the Alooideae which I felt was unacceptable because of the fallacious character states and sets that were used there Despite that paper and at least four others Smith 1991 1994 1995 Smith van Wyk 1992 generally supporting the unispecific status of Poellnitzia Manning and Smith 2000 incorporated the genus in Astroloba My objection to this manipulation of the genera is that the supporting arguments have been incorrect and that it essentially has not addressed or considered what I perceived to be the stumbling block to arriving at a better delimitation of the genera in the sub family This is the relationship within the genus Haworthia where it is quite evident to me that it comprises three distinct sets of species the subgenera of Bayer ex Uitewaal The floral and morphological differences for those three sets are absolute and I am sure will need to be seen so in any way in which Aloe is configured This is because the floral similarities within those subgenera are so minimal I consider these floral differences to be as dramatic for genus delimitation as any of the character states covered in Rowley s 1967 analysis It would alarm me if the result of a DNA study produced any other result The sets also appear to me to be behaviorally different and with this consideration the genera even if unispecific Poellnitzia Chortolirion Astroloba are of similar status This is not to imply that I do not recognise the problems with many other oddities in the Alooideae which require re evaluation of the generic arrangement Adam Harrower of NBI asked me to identify an Haworthia he had collected near the Potberg cf H heidelbergensis In view of his interest I asked him to lookout for H limifolia on a trip he was to undertake to the eastern Transvaal On his return he presented to me a plant he took to be that species It was in fact Chortolirion angolense However he produced photographs of another species at which I exclaimed This is a new genus Here I recognize the irony of this reaction when the generic arrangement in Aloe is so questionable The plant that Harrower collected has thin slender spineless hyacynthoid leaves Figs 1 2 with very pronounced bulbous bases There seem to be few accumulated dry bulb scales as in Chortolirion and the plants have not displayed deciduousness as does that species The blades of the older leaves dehisce leaving fleshy bulbous bases and these are spirally arranged in the lowest order of the Fibonacci series viz 2 3 or 5 Fig 2 The roots seem rather sparse and are the yellowish color of Aloe The flower intrigues me more figs 3 4 The free terminal portions of the flower are not channeled but are flared in the style of the sub genus Haworthia The midribs of the inner petals remain exposed and the margins of the outer petals adhere close to the mid rib of the inner This is the case in the subgenus Hexangulares and Chortolirion as well as in this new genus The lower petals are more undershot than is the case in either the Hexangulares or subgenus Haworthia The geographical location is the high lying escarpment between the ranges of the species H koelmaniorum and H limifolia of the Haworthia subgenus Hexangulares Why I have stated so categorically that this is a new genus is largely because of the historical mal treatment of the genera of Alooideae and the failure of students and commentators of Haworthia to exhibit any rational species concept Such a concept appears to be missing for the genera as well These shortcomings coupled with the name changes which would ensue have discouraged me from ever trying to formalize three distinct genera for Haworthia What has troubled me in recent times is the emerging belief that molecular study will provide the basis for a real and irrefutable phylogenetic classification We have now a paper published in Taxon 52 193 2003 see reprint pages 6 21 by Treutlein et al which will enable one to see to what extent these expectations are being met What strikes me immediately about the paper is firstly a statement in the abstract and secondly the unfortunate selection of study material The abstract summarizes the results of the work done and this is The current taxonomic system does not reflect the phylogenetic affinities and relationships among the succulent genera Aloe Chortolirion Gasteria Haworthia and Poellnitzia I find this extraordinary as it has never occurred to me that it did and I would have expected this sentence to be worded in such a way as to form a key question to be answered by the study rather than as a conclusion Similarly Treutlein s closing paragraphs of his discussion should have been used as key questions to be answered by the study and not have been derived from it One sentence reads complete sampling needed The selection of material I take to be somewhat irresponsible given the past history of classification of the group and the literature I would have expected some kind of predictive approach to the selection of material The inclusion of unknown hybrids such as H ryderiana H kewensis and H icosiphylla can tell us nothing Ignorance of the actual taxonomic position of H geraldii is similarly curious The material is virtually entirely ex hortus and given my experience with identification even voucher specimens are hardly likely give such material much credibility I do think more thought and consideration should have been given to the species used in relation to the problems they present to their classification Putting these considerations aside I would comment as follows on the results as presented primarily in Treutlein et al s fig 4 It does tell me what I had supposed i e subgenus Haworthia is very different from the other
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