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The map below is scanned from the Flora of Southern Africa (FSA), Crassulaceae, Vol. 14 (1985) by H. R. Tölken. I coloured and aligned it with Tölken's caption, as supporting material for a collection of A. marianiae forms exhibited at the BCSS National Show at Spalding in August 2004. It illustrates the division of this species into four varieties plotted against the Atlantic coast-line. Tölken (1978) wrote:

"A. marianiae is an extremely variable species, occurring from near Clanwilliam to just north of the Orange River. Recent collections show a continuous range of variation, leading to distinct extreme forms in isolated localities. After considerable field studies, it was found that most of the transitional ranges between extreme forms are restricted to areas where taxa apparently come into close contact with one another. As whole ranges of variation are found within these areas, introgressive hybridization is considered to be taking place. The map shows a selection of the full range of variation and the geographic distribution of certain characteristics, but it also illustrates why certain species have been relegated to synonymy as four varieties."

Since then, more sampling over a wider area has revealed even greater variation, supporting the nine taxa recognised in this web site. For example, "hallii" with broad leaves is quite widespread on white quartzite outcrops. Click here to see how variable a single A. marianiae population can be.

Variation in shape, size & surface texture of leaves and the type of roots is shown. Samples with a smooth leaf surface have open triangles, with solid triangles for a verrucose leaf surface. Samples with tuberous roots are in squares, with fibrous roots in diamonds.

Tölken's Map of Adromischus marianiae Distribution

These are all forms of the variable A. marianiae complex, in 5 or 7 cm. sq. pots.
Third prize, class 122, thematic exhibit up to 24" square, BCSS National Show 2004. Photo: David Offord.

Last Updated: Mar 2005

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© 2005 Derek Tribble, London, UK