Stapeliads of Southern Africa and Madagascar, 2 vols., by Peter V. Bruyns. 2005. Umdaus Press, Hatfield, South Africa. Vol. I – ISBN 1-919766-37-5, Vol. II – ISBN 1-919766-38-3.

Like a femme fatale, Peter V. Bruyns’ “Stapeliads of Southern Africa and Madagascar” is stunningly beautiful and seductive. This is what every monograph should be; rich with information, loaded with wondrous photography and illustration. And yet, it’s the first effort in 70 years to take a renewed look at this fascinating group of plants. Is this why she’s so attractive? Has it been so long that aficionados are willing to risk her dark secrets to make her the one? Does “Stapeliads” become the standard reference in the field by default—because the subject is so arcane that it is rarely dealt with; or because its conclusions stand the test of time and examination by others?

Bruyns is a research associate at the Bolus Herbarium at the University of Cape Town in South Africa and a prolific author, photographer and illustrator of popular and scientific articles. He is an acknowledged authority on the succulent Apocynaceae, and, although he has his critics, his word is getting wide play. “Stapeliads” has set a high bar, not only for future treatments of this group, but for books about plants in general. It is a splendid, comprehensive look at a subset of plants, accessible to scientific, professional and lay audiences.

The last monograph on stapeliads “The Stapeliae” was the three-volume effort of White and Sloane in 1937. It has long been the standard, and is still a valuable historical addition to the succulent lexicon despite significant alterations to the stapeliad landscape over the intervening years. Its biggest shortcoming is that it is based on plants in cultivation. Much of the value of Bruyns’ work is that it comes out of over 25 years of experience in the field. Couple that experience with the decades of discovery and analysis since the publication of White and Sloane, and the lack of a comprehensive opposing viewpoint, and “Stapeliads” becomes the de facto standard.

“Stapeliads” is restricted in scope, being confined to the representatives of this group of succulent plants from southern Africa (Botswana, Mozambique, Namibia, South Africa Zimbabwe) and Madagascar. This results in discussion of 182 of 328 species that Bruyns recognizes. Of these 182, roughly 92% are endemic to the area covered by the books. A third volume is rumored to be in preparation to address the species of northern Africa, Arabia, southern Europe, and Asia, to complete the survey.

The book opens with a historical sketch. As implied by its characterization, it is short and unfortunately concludes without mention of the contributions of recent toilers in the field; explorers, horticulturists, and scientists—including the new generation of stapeliad researchers in the Czech Republic.

It quickly moves on to fascinating sections on classification, morphology, pollination biology and discussion of biogeography. The section on morphology is especially welcome and is heavily illustrated with the author’s superb line drawings as well as photographs, and intimate views of flower structures courtesy of scanning electron microscopy. A detailed look at the distribution and diversity of the group brings context and a sense of place to the discussion in the section on biogeography. A short but useful discussion on cultivation and a one page survey of human uses of stapeliads round out the introductory material.

The bulk of the two volumes is composed of the treatment of the twenty genera (Australluma, Baynesia, Duvalia, Hoodia, Huernia, Larryleachia, Lavrania, Notechidnopsis, Ophionella, Orbea, Pectinaria, Piaranthus, Quaqua, Richtersveldia, Stapelia, Stapelianthus, Stapeliopsis, Tavaresia, Tridentea and Tromotriche) Bruyns recognizes in the geographic scope of this work--their species, subspecies and varieties; and a look at hybrids. Each entry contains a formal description and copious notes on distribution and habitat, diagnostic features and relationships, and history. Keys to subspecies and varieties are added when necessary.

Detailed line drawings are useful for analyzing the differences between closely allied taxa and color photography is liberally used to show the species in habitat and evidence the variation within species.

Bruyns taxonomic treatment of the group has not passed without comment. In “Stapeliads” he publishes 25 new combinations to add to the growing list of changes he has made during the course of his career. Despite these new entities, Bruyns is viewed by some as a lumper, collapsing the work of others in a sometimes controversial fashion. Taking a broader, more conservative view, Bruyns combines what he feels are “unjustified and pointless” splittings, particularly in taxa that exhibit great variation in a small geographic range. He is critical of past taxonomic efforts based, he claims, on the “folk concept” of species that has “largely held sway among the stapeliads.” To his credit he elucidates his species concept before plunging into the fray.

This struggle is common to all attempts to name and classify. Taxonomists have disagreed with each other throughout the course of the discipline and will continue to do so. While DNA analysis has been done at the family level, and has helped to sort out relationships at that higher taxon, work at the genus and species level has only started within the past five years, and traditional efforts using morphological characteristics continue to be employed. In another publication, Bruyns writes, “It must be emphasized that the “final” solution to the problems surrounding the delimitation of the genera has not been found. Even the molecular techniques, that have often been touted as the solution to all taxonomic problems, have failed to resolve many of these problems satisfactorily.” (Bruyns, P.V., (2002). The Southern African genera of the stapeliads. Aloe, 39:3&4:52-63).

Molecular data suggests groupings, based on markers, that aren’t particularly well supported by the data and/or where there is no morphological information to substantiate and corroborate the conclusion. Ironically the limited analysis done to date hints that the group may be more complex than Bruyns is willing to admit at this time.

Mention must be made of the incredibly high production standards of Umdaus Press. These volumes are well and attractively bound, made with high-quality paper, and finely printed in Singapore. Each contains a ribbon marker, a beautiful cover, and the pair are slipcased to protect their bindings. Even the endpapers are remarkable. Obviously from the pen of the author, they are fields of stapeliad flowers and their gynostegia, meticulously line-drawn and as unique as snowflakes.

Time will tell whether the vexing problems surrounding the defining of the stapeliad genera and their species will be resolved by the acceptance of Bruyns’ conclusions, or the work of others. In the meantime, and regardless of your view of the taxonomy employed, allow yourself to be seduced by “Stapeliads of Southern Africa and Madagascar.” It’s a valuable addition to the succulent library—at least until the next beauty rounds the corner.

[This review first appeared in Brittonia: A Journal of Systematic Botany, published by The New York Botanical Garden]

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Copyright  2006- 2007 by Carlo A. Balistrieri.
All rights reserved.