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Plant Galls of Europe

A three-volume standard work on galls in Europe. Author Johannes C. (Hans) Roskam is associate professor emeritus in Evolutionary Biology and currently guest at Leiden University.

JC Roskam
13 September 2019
KNNV Publishing

About the book

In 1964-1965 Herbert Buhr published his ‘Bestimmungstabellen der Gallen (Zoo- und Phytocecidien) an Pflanzen Mittel- und Nordeuropas’. These keys were developed in the great tradition of cecidology intiated by specialists such as Rübsaamen, Ross and Hedicke in Germany; Barnes, Connold, Bagnall & Harrison and Swanton in Great Britain; and Kieffer and Houard in France.

During the second half of the twentieth century a new generation of cecidologists expanded significantly our knowledge of plant galls and their distribution; new gall books were published covering several countries.

In an era in which urbanization did change climates, habitats and biodiversity dramatically, we felt a need to collect this new knowledge and incorporate it into a revision of Herbert Buhr’s monumental work in order to make it accessible for future generations. This because galls are important examples of intriguing interactions between an astonishing variety of as well animals as fungi and plants, produced by evolutionary processes of which even today the mechanisms are still largely unknown.

We concentrated on Buhr’s keys, but implemented additions, especially for Southern Europe, from Houard (1908-1913): Les zoocécidies des plantes d’Europe et du bassin de la Méditerranée. A chapter elaborating specifically the taxonomic associations between plants and gall makers, not available in the current literature, has been added. The nomenclature of as well gall inducers as host plants has been updated. Information about specific groups of gall inducers has been reviewed and new insights were implemented.

To the proxy 9,000 galls and malformations described by Buhr and Houard, we added about 1,250 new galls which have been described in the more recent literature. Moreover, we collected distribution data for total Europe and, if available, adjacent areas. Even in the era of computers, this was a 9-years during full time project, only possible with the help of about 10 top specialists, and the facilities of our Institute of Biology Leiden. The result is a 3-volume work comprising proxy 2,300 pages including 32 plates with more than 500 figures.

Johannes C. (Hans) Roskam (1943) is associate professor emeritus in Evolutionary Biology and currently guest at Leiden University. His PhD covered a biosystematic analysis of associations among birches, gall midges and their parasitoids. He revised earlier W.M. Docters van Leeuwen’s Gallenboek (Plant Galls) 4th edition, 2009.

J.C. Roskam: Plant Galls of Europe. KNNV Publishing, Zeist, The Netherlands, 3 volumes, 2300 pp.

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