CA Mushrooms
CA Mushrooms

Book Review

Myxomycetes: Biology, Systematics, Biogeography, and Ecology

Edited by Steven L. Stephenson & Carlos Rojas
2017; Academic Press
ISBN 978-0-12-805089-7
paper, xx + 454 pp

Most of the people who notice slime molds are probably mushroom hunters. I doubt that many birders, with their eyes cast upward, see them, even though some do occur in the canopy. Thus it seems logical that a review of a book about myxomycetes (“slime fungi”) would appear in a publication about fungi, even though the myxos actually do not belong to the kingdom Fungi. Exactly where they fit in the tree of life is still a matter of debate but suffice to say they are eukaryotes, but neither plants, nor animals, nor fungi, part of a diverse group of organisms traditionally referred to as protozoans or protists. More specifically, myxomycetes are described as amoeboid protists. An amoeba is a type of cell or unicellular organism which has the ability to alter its shape, primarily by extending and retracting outgrowths of the cell called pseudopods, which can serve in locomotion and feeding. Amoebas do not form a single taxonomic group; instead, they are found in every major lineage of eukaryotic organisms, including fungi, algae, and animals.

For the record, “myxomycete” and “slime mold” are not synonymous (although I plead guilty to having used them as such). To be precise, Myxomycetes refers to the so-called plasmodial slime molds or myxogastrids only. Other slime mold groups include the Protostelia and Dictyostelia and these three groups that form fruiting bodies also have close amoeboid relatives within the Eumycetozoa that are non-fruiting. Myxomycetes are free-living predators of other protists and bacteria and, according to the book’s editors, have been found in every terrestrial habitat investigated to date. The two feeding stages of the life cycle (amoeboflagellates and plasmodia) generally are not visible, but the fruiting bodies often are large enough to be seen if one knows where to look for them. As is the case for mushrooms, the fruiting bodies produce and release spores that are dispersed primarily by air and that, under favorable conditions, germinate and give rise to amoeboflagellates, from which the plasmodium is ultimately derived. Myxomycetes are associated with a wide variety of different habitats/ substrates, the most important of which are coarse woody debris, leaf litter, and the bark of live trees.

In the Introduction, the editors state that “The primary objective of this volume is to provide an overview of the majority of what is currently known about this truly interesting group pf organisms ... It is our desire that [it] serve as a source of information that can help increase general bioliteracy by opening the door to the world of myxomycetes for the layperson, as well as representing a comprehensive reference work on the biology, systematics, biogeography, and ecology of the group for the expert … The intent of the editors and the collaborators has been to reach out to students, naturalists, and academics equally.” The latter is a difficult goal to achieve.

Further, “In addition to chapters dealing with different aspects of myxomycete biology, such as biochemistry, phylogeny, taxonomy, ecology, and distribution, readers will find that contextual topics, such as history of research, isolation techniques, biophilic potential, uses and applications, and educational value, have also been included. The idea behind this strategy has been to incorporate different approaches that are not normally considered in ‘more difficult’ scientific texts but which are very important if one is to understand the context within which myxomycetes have been studied.”

Including the editors, the authors include 29 contributors from 12 countries, representing the Americas, Europe, and Asia. The 13 chapters cover a wide gamut of topics, some accessible to a general readership and others better suited to specialists or at least those with more advanced biological backgrounds. 1. The myxomycetes: introduction, basic biology, life cycles, genetics, and reproduction. 2. The history of the study of myxomycetes. 3. The phylogeny of myxomycetes. 4. Genomics and gene expression in myxomycetes. 5. Molecular techniques and current research approaches. 6. Physiology and biochemistry of myxomycetes. 7. Taxonomy and systematics: current knowledge and approaches on the taxonomic treatment of myxomycetes. 8. Ecology and distribution of myxomycetes. 9. Biogeographical patterns in myxomycetes. 10. Techniques for recording and isolating myxomycetes. 11. Uses and potential: summary of the biomedical and engineering applications of myxomycetes in the 21st century. 12. Myxomycetes in education: the use of these organisms in promoting active and engaged learning. 13. Myxomycetes in the 21st century. All of the chapters have at least two authors and each concludes with a lengthy list of references that those interested in pursuing particular topics further will find quite useful.

My favorites were the first two chapters – the first for refreshing my memory about what these organisms are and the second for helping me realize that many past students of the group are the same ones who collected and studied the mushroom fungi. I also found the ecology and biogeography chapters to be particularly interesting. As would be expected in a multi-author edited work, the writing style varies from chapter to chapter. Despite that stated intent of appealing to readers of varied experience reading scientific literature, many of the topics covered will require the reader to be reasonably conversant with basic college biology and chemistry to get the most from the discussions.

Although somewhat textbook like in its content, the volume is not illustration-heavy. Color and black-and-white illustrations and photographs are scattered throughout and are mostly helpful. Most are not as sharp as one would like, as the paper used has a matte rather than smooth finish. This is most noticeable with the smaller figures. The book provides a valuable compilation of what is known about the myxomycetes that would be very useful for those with a keen interest in the group, along with deep pockets or a nearby college library. Unfortunately, the far-too-high price likely will prevent it from having much of an impact on general bioliteracy.

— Review by Steve Trudell
— Originally published in Fungi