The Genus Hebeloma
This is the third volume of the series that was initiated by David Boertmann’s Hygrocybe volume and Hebeloma shares the attractive look and excellent functionality of its predecessors. The preface provides a succinct summary, “... here we are given the best ever and fully illustrated overview of a particularly difficult genus ...” with which I agree. Vesterholt, who regrettably passed away recently at a much-too-early age, was an amateur, though professional-caliber, mycologist and he had been studying Hebelomas since the early 1980’s. Among other accomplishments, he was co-editor of the fine compendium, Funga Nordica, which further attests to his stature in the European mycological community.
After the preface, Vesterholt summarizes his methodology and provides an extensive taxonomic description of Hebeloma, covering both the macroscopic and microscopic features, and his systematic arrangement of taxa within the genus. He then discusses the habitats in which hebelomas are found and their role as ectomycorrhizal symbionts in those ecosystems. Next, he presents keys to the species. They include a mix of macroscopic features, microscopic features, and habitat information and have worked well for me.
The main section of the book contains the descriptions, and here’s where it really shines. Each species receives at least two pages that include a comprehensive but succinct description, comments on ecology and distribution, and a discussion of the taxon in relation to possible lookalikes and other taxonomists’ concepts. Amateur mycologists will appreciate that Vesterholt uses fairly broad species concepts. Illustrations for each taxon include very high quality color photographs that are particularly effective for identification and drawings of spores and cystidia. A difference between this volume and Hygrocybe is that this one includes no distribution maps. Vesterholt felt that because of the difficulty in identifying the species, the available data could not be relied on for production of accurate maps.
The back sections include a compilation of data on the material studied, list of color names corresponding to Kornerup and Wanscher (the “Methuen” color guide) designations, five pages of references, and index.
Although it might seem impossible that there could be so many different basic (some might say boring) brown mushrooms, 45 northern European species are included here. Vesterholt made it clear that this is a minimum estimate of the actual number, as molecular studies suggest many additional entities exist and await work to determine whether they can be recognized by morphology. His descriptions are based primarily on material he collected and many of the collections on which the book is based have been sequenced, so he had a sound basis for that opinion.
It is hard to know how many of the 45 species in the book also occur in North America, as our species have received very little critical study. Perhaps this is to be expected of a group whose species look very much alike, are hard to identify, and are not edible. The only extensive treatment of hebelomas here is The Veiled Species of Hebeloma in the Western United States, by Smith, Evenson, and Mitchel (1983), but, for me at least, this is a very difficult volume to use and many of the species included in it seem an awful lot like the same thing. I suspect, however, that many of the species treated by Vesterholt do occur in North America, particularly in the northern portions of the continent, so this book would make a good starting point for someone interested in tackling identification of our hebelomas.
Thus, like Hygrocybe and Lactarius before it, this is a first-class effort. Despite his favorite fungi not having the eye-catching beauty of the hygrocybes and many lactariuses, Vesterholt did a fine job producing an attractive and functional contribution to the mycological literature.
— Review by Steve Trudell, Seattle, WA
— Originally published in Fungi