A biosytematic [i.e. biosystematic] study of the seven minor genera of the Hyacinthaceae

Van der Merwe, Alison M. (Alison Mary) (Stellenbosch : Stellenbosch University, 2002-03)

Thesis (DPhil)--Stellenbosch University, 2002.

Thesis

ENGLISH ABSTRACT: A biosytematic revision of the seven minor genera of the Hyacinthaceae, including twenty-two species, was undertaken. Muller-Doblies & Muller-Doblies (1997) considered these seven genera (Amphisiphon Barker, Androsiphon Schltr., Daubenya Lindl., Massonia Thunb. ex Houtt., Neobakeria SChItL, Polyxena Kunth and Whiteheadia Harv.) together with the genus Eucomis L'Herit. to form the subtribe Massoniinae of the tribe Massonieae. Previous revisions of the group were based only on morphological characters (Jessop 1976; Muller-Doblies & Muller-Doblies 1997). The subtribe Massoniinae is characterised by the large variety of floral forms exhibited by the different species in the group. In the past this has led to the establishment of many monotypic genera for species thought to have unique floral structures. Morphological, leaf anatomical, palynological, geographical and molecular data were studied in order to delimit the taxa and determine the phylogenetic relationships within the group. This showed that most of the unique floral structures are probably only adaptations to pollination strategies and all except one of the monotypic genera are now placed in the genus Daubenya. In the genus Massonia there is a great deal of variation in leaf morphology and this resulted in the establishment of many invalid species, now mostly reduced to synonymy. A new species was described, several name changes made and several species were reduced to synonymy.

AFRIKAANSE OPSOMMING: 'n Biosistematiese hersiening van die sewe kleiner genera van die Hyacinthaceae, insluitende twee-en-twintig spesies, is onderneem. Muller-Doblies & Muller-Doblies (1997) sluit hierdie sewe genera (Amphisphon Barker, Androsiphon Schltr., Daubenya Lindl., Massonia Thunb. ex Houtt., Neobakeria Schltr., Polyxena Kunth and Whiteheadia Harv.) saam met die genus Eucomis L'Herit. in die subtribus Massoniinae van die tribus Massonieae in. Vorige hersienings van die groep was meestal net op morfologiese kenmerke gebaseer (Jessop 1976; Muller-Doblies & Muller-Doblies 1997). Die subtribus Massoniinae word gekenmerk deur die groot variasie in blomstrukture wat by die verskillende spesies in die groep voorkom. In die verlede het dit gelei tot die beskrywing van verskeie monotipiese genera gegrond op wat geblyk het, unieke blomstrukture te wees. Morfologiese, blaar anatomiese, palinologiese, geografiese en molekulere data is bestudeer om die verskillende taksons af te baken en terselfdertyd die filogenetiese verwantskappe binne die groep te bepaal. Dit het aangetoon dat die unieke blomkenmerke eerder aanpassings aan bestuiwings-strategiee is en dat al hierdie monotipiese genera, behalwe een tot die genus Daubenya behoort. In die genus Massonia is daar baie variasie in blaarmorfologie en dit het veroorsaak dat 'n groot aantal spesies beskryf is, waarvan baie nou as sinonieme beskou word. Een nuwe spesies is beskryf, verskeie naarnsveranderinge is gemaak, en 'n aantal van die spesies is tot sinonieme verander.

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