Part 1/3 of Engler's Syllabus of Plant Families - Basidiomycota and Entorrhizomycota provides a thorough treatise of the world-wide morphological and molecular diversity of the fungal phyla Basidiomycota and Entorrhizomycota.
The Basidiomycota (Pucciniomycotina, Ustilaginomycotina, Agaricomycotina) are an extremely diverse group of the fungi with c. 36000 species, with a fascinating range of morphological and biological variation, distributed from the Antarctic, arctic tundra to tropical rainforests, and of high economic value. Many species of Agaricomycotina play a role in human food, most important and of greatest economic interest are the parasitic Pucciniomycotina and Ustilagomycotina. The Entorrhizomycota are plant root associated fungi and seem to represent a lineage of living fossils which links Glomeromycota, Ascomycota and Basidiomycota in a probable common origin.
The present volume is, as the formerly published volumes of the Syllabus, an updated synthesis of classical anatomical-morphological characters with modern molecular data, incorporating numerous new discoveries made during the last ten years, providing a comprehensive modern survey covering all families and genera of the Basidiomycota and Entorrhizomycota including detailed family descriptions.
Following the tradition of Engler, and incorporating the latest results from molecular phylogenetics and phylogenomics, the completely restructured and revised 13th edition provides an up-to-date evolutionary and systematic overview of the fungal and plant groups. It is a mandatory reference for students, experts and researchers from all fields of biological sciences, particularly botany, phycology and mycology.
While the Fungi are not part of the Plant Kingdom, they are formally included within the classic Engler's title "Syllabus der Pflanzenfamilien / Syllabus of Plant Families", which comprised families of blue-green algae, algae, fungi, lichens, ferns, gymnosperms and flowering plants.

The Ascomycota volume in this series appeared in 2016 (see IMA Fungus 7 (1): (45), June 2016). The style is essentially the same as for that volume, with one important and most valuable improvement. In the Ascomycota, descriptions were given down to the rank of family, followed by a list of included genera (with selected synonyms) with indications of species numbers. Genera which cannot be assigned to particular families or orders are not forgotten and treated “incertae sedis”, and even fossil genera are included. While there are no keys, there are most valuable notes of the distinguishing characters even of the individual genera, along with indications of habitat and areas where they are known (in many cases to continents or countries). This makes this of pivotal importance as no such complete sets of diagnoses for basidiomycete genera have been attempted since those included in the keys presented in Ainsworth et al. (1973). There are also sometimes extensive lists of “references and further reading”, mainly at the ends of the treatments of particular classes. The illustrations are superb, and include some of ultrastructural and microscopic features and not only basidiomes. Phylogenetic trees are scattered through the volume to show the relationships of higher taxa, and there is a comprehensive index down to the level of genus. The classification of basidiomycete fungi has been transformed dramatically in the molecular era, and that adopted here is not only topical but incorporates some changes. Two subclasses are newly emended (Gomphanae and Tremellomycetidae) and Agerer introduces four new subclasses (Cantharellomycetidae, Filobasidiomycetidae, Hymenochaetomycetidae, and Trechisporomycetidae), and three new superorders (Agaricanae, Phallanae, and Russulanae); sadly, none of these names appears to be validly published as, while diagnoses are provided, no identifier from any of the three approved repositories of newly proposed fungal names is cited. The tendency is for most recent segregates of formerly broadly circumscribed genera such as Boletus and Hygrocybe to be recognized, while the acceptance of families has been more conservative. As noted for the Ascomycota volume, it would have been helpful to include the years of publication of the taxon names to add to the completeness of entries. And while I wholeheartedly welcome the absence of “fruit body”, I would have preferred to see “basidiome” taken up rather than the “basidiocarp” the authors adopted as the latter word still has botanical connections. I find it difficult to believe that this book has been put together by just three mycologists. Begerow and McTaggart are given as responsible of all sections apart from Agaricomycotina which was evidently contributed by Agerer alone. This is a truly remarkable achievement, a landmark in basidiomycete systematics, and a work that really is a “must have” for both mycological institutions and departments as well as all basidiomycete systematists.

IMA FUNGUS Book News, Volume 9 No. 2, 12/2018

Gustav Heinrich Adolf Engler, 1844–1930, was a German botanist and plant geographer. His best-known publication (with Karl von Prantl) is Die natürlichen Pflanzenfamilien (The Natural Plant Families) published in parts from 1887 to 1911. In this work, Engler and Prantl provided a comprehensive system of plant classification that became widely accepted and was the principal one used in herbariums and elsewhere worldwide until the 1970s. Engler’s Syllabus der Pflanzenfamilien, which first appeared in 1892 under a different title, is essentially an outline summary of the larger work. Taking on a life of its own, many subsequent editions of the Syllabus appeared, and it was continued by others after Engler’s death. The most recent edition was the 12 th in 1954. The 13 th edition, the first in English, began in 2009 with the publication of Part 3, Bryophytes and Seedless Vascular Plants, and has continued with the release of additional parts in 2012, 2015, 2016, and 2017.
So why are we interested in a book about plants originally written by a botanist? Because, until rather recently, fungi were considered to be plants and so they, along with cyanobacteria, algae, and lichens, were treated by Engler along with the real plants. This is the third of three (sub)parts of the Syllabus that deal, fully or in part, with fungi. Part 1/1, published in 2012, covers, along with a variety of non-Fungi things, the Chytridiomycota, Zygomycota, and Glomeromycota. Part 1/2, reviewed in the Fall 2016 issue of FUNGI, treats the Ascomycota. Last, but not least (and actually the most, if you count pages), Part 1/3 deals with the Basidiomycota (comprising the sub-phyla Pucciniomycotina [the rusts], Ustilaginomycotina [the smuts], and Agaricomycotina [the mushrooms, in a very broad sense]) and the Entorrhizomycota.
The authors are well aware of the difficulty in producing such a comprehensive work when the classification of fungi, as well as that of other organisms, is undergoing such rapid and widespread change as a result of the accumulation of data from molecular sequencing. Thus, they view this as nothing like the final word, rather as a snapshot of a work in progress. In the Preface, the editor of the series (Wolfgang Frey) describes the new edition of the Syllabus as “Following the tradition of Engler, and incorporating the latest results from molecular phylogenetics and phylogenomics, this completely restructured and revised 13 th edition provides an up-to-date evolutionary and systematic overview of the fungal and plant groups.” As was stated in Part 1/2, “phylogenetic revisions have revolutionized the systematic classification of taxa from phylum to species level and a new understanding of fungal evolution and species delimitation has emerged. These new insights are here treated in an integrated context of morphological and molecular data, providing an up-to-date synopsis ... while acknowledging that the systematic classification of this group of Fungi is not yet fully settled.” The latter is somewhat of an understatement.
Be forewarned, this is not an enthralling page-turner unless you happen to be an ultimate taxonomy nerd. It is a reference work that likely will sit on your shelf until you need to learn something about a basidiomycete whose name you have encountered for the first time or to find out who is thought to be close cousin of whom, especially in light of the decreasing degree to which macro appearance is thought to faithfully reflect evolutionary relationships. Following a one-page Introduction (Chapter 1), Chapter 2 provides a succinct summary of the phylum, Basidiomycota, basidiomycete morphological characteristics and life cycles, ecology and distribution, and systematic arrangement of taxa. Given the tiny size of the Entorrhizomycota, two genera and 15 species, it receives only occasional mention. (By the way, this phylum includes species that occur within the roots of sedges and rushes. They are thought to be parasitic, and cause the formation of galls on the root tips. Here the group is included in Dikarya, along with the Ascomycota and Basidiomycota, but that placement should be considered tentative.)
Chapter 3 consists of a 7-page synopsis of the classification of the Basidiomycota and Entorrhizomycota, the latter consisting of a mere six short lines of text. Chapter 4, Systematic Arrangement of the Taxa of the Basidiomycota, makes up the bulk of the book (more below), Chapter 5 does the same for the Entorrhizomycota, and Chapter 6 gives us nine new or amended sub-classes or super-orders. A list of references for the figure captions and an index to taxa complete the book. General references are placed throughout the book after the appropriate sections.
Following the outline provided in Chapter 3, Chapter 4 cycles through the subphyla, classes, orders, families, and genera, providing brief descriptions of each taxon, numbers of lower-level taxa within them, and reference citations (there is a huge number of them). Having descriptions of genera is a welcome change from the Ascomycota volume, in which descriptions were provided only to family level. The addition of these descriptions accounts for the much higher number of pages in this Part, even though Basidiomycota contains far fewer genera (~1840 vs. ~6100) and species (~36,000 vs. ~57,000) than Ascomycota. Within the subphyla Pucciniomycotina and Ustilaginomycotina, the entries are arranged alphabetically. Within the Agaricomycotina, the higher-level taxa follow a phylogenetic order, whereas the families and genera are arranged alphabetically.
Illustrations are placed at the end of major sections, and include color photographs, black & white photographs, line drawings, and phylogenetic trees. Most of the photos and drawings are grouped into plates (although they are referred to as “figures”) that typically include a dozen or more individual images that principally illustrate macroscopic and microscopic morphological features. Though individual images mostly are rather small, they are of good to high quality. My only reservation is that, in cases where the subject is relatively large (like many of the mushrooms, for instance), it is very difficult to see much detail.
Those with an interest in the entorrhizomycetes will probably not find this volume worth the price given that their fungi merit only two pages of coverage. However, it will be a necessity for anyone making a serious study of the basidiomycetes and will no doubt find a place in most university mycology labs and libraries. I view the inclusion of genus descriptions as a major benefit likely to increase the usefulness of the volume relative to its predecessors. Although it could well come in handy for many non-affiliated folks, the price is likely to prevent it from finding its way into the personal libraries of most amateur mycologists.

Steve Trudell

FUNGI Volume 12:1, Spring 2019

This volume represents the final installment dealing with Kingdom Fungi within the thirteenth edition of the recently resurrected Engler’s Syllabus of Plants Families. This new version of the classic series considers the major groups of diverse organisms once treated as “plants” (and still often taught together introductory botany classes), subjecting each to a contemporary biosystematic overhaul that utilizes the most recent data sets and current phylogenetic principles. The basal groups of true Fungi were treated in a previous volume (Part 1/1), which also included myxomycetes, heterotrophic stramenopiles such as the oomycetes, and, unexpectedly, the cyanobacteria, whereas the Ascomycota were dispatched in their own volume (Part 1/2, reviewed in PSB 63[3]:116). Although the rationale for how the series is organized at the broadest levels is not always clear, a predictably phylogenetic scheme is followed within each major group considered. The present volume treats the Basidiomycota, plus a page and a half dedicated to the Entorrhizomycota, a small, isolated clade of root parasites once thought to have affinities among the smut fungi but now placed in uncertain relationship to the Dikarya and Glomeromycota.
The Basidiomycota are currently resolved into three major clades: the Pucciniomycotina, the Ustilagomycotina, and the Agaricomycotina. The first of these includes not only the rust fungi (Pucciniales), a familiar group of obligate plant parasites, but also a considerable diversity of less well-known fungi with diverse structure and ecology, some of which even produce fruiting bodies. The fungal kingdom’s most complex life cycles occur in this group, where a single species may show as many as five different spore types and two distinct, obligate plant hosts. The second subphylum, Ustilagomycotina, encompasses mainly plant parasitic fungi, most notably the smuts, that show characteristic interaction zones ultrastructurally at the fungus-host interface, now considered a synapomorphy for the group. The third subphylum, the Agaricomycotina, includes the bulk of the Basidiomycota, and particularly the diverse fleshy fungi most familiar to the field mycologist and forager. They obtain carbon as saprotrophs, parasites, mycorrhiza-formers, and lichen-formers.
Many useful figures —color photographs, light and electron micrographs, and line drawings — are provided. All figures are arranged in plates grouped together at the end of the text treatment of each of the three subphyla. The organization is not particularly user-friendly. The figures are called out in the text not by page number but according to plate and figure number, making it more time-consuming to find them. Furthermore, the legends are all grouped apart from the figures themselves, so one needs to triangulate among three separate locations to interpret the images in context. For the Pucciniomycotina and the Ustilagomycotina, a cladogram is provided among the figures, helping the reader to place the taxonomic scheme in phylogenetic context. Unfortunately, however, no cladogram is provided for the Agaricomycotina, the largest of the three subphyla and the one that includes most of the macrofungi. These taxa have undergone profound rearrangement in the last few decades, with once-familiar groupings of commonly observed fungi such as the “aphyllophorales” and “gasteromycetes” now dissolved in favor of new placements that are more meaningful phylogenetically but often unexpected morphologically. A cladogram would help the reader assimilate these changes and better appreciate the extent to which convergent evolution has repeatedly generated the same syndromes in basidiocarp structure and spore dispersal. It’s a bit disappointing that the text barely comments on such trends. Indeed, there is little text discussion at all; most of the prose consists of character description lists for each taxon considered. The fungal taxonomist will surely appreciate the authors’ painstaking work in compiling and systematizing the current state of basidiomycete diversity, but the paucity of discussion means that this work will serve primarily as a reference tool rather than as any sort of textbook.
In many places, the text would have benefited from copyediting by a native-speaking proofreader. There are many instances where errors of grammar, punctuation, and diction require one to pause and re-read, although ultimately most meanings are clear from context. No glossary is provided. The Dictionary of the Fungi (or similar reference) will therefore be needed to interpret the specialized terminology that abounds in the character descriptions, as well as to distinguish some typos from unfamiliar terms (e.g., [sic:] teilospores, peridal, biozonate, hypgrophanus...).
Imperfections aside, this volume is clearly a significant work that provides a thorough, contemporary treatment of a fungal class that is of central importance in the biosphere.

William B. Sanders, Florida Gulf Coast University

Plant Science Bulletin 65 (2) 2019