Book review: Mites of freshwater mollusks by Edwards D.D. and Vidrine M.F. 2013

Abstract

Subscriptions: Year 2017 (Volume 57): 380 € http://www1.montpellier.inra.fr/CBGP/acarologia/subscribe.php Previous volumes (2010-2015): 250 € / year (4 issues) Acarologia, CBGP, CS 30016, 34988 MONTFERRIER-sur-LEZ Cedex, France ACAROLOGIA A quarterly journal of acarology, since 1959 Publishing on all aspects of the Acari All information: http://www1.montpellier.inra.fr/CBGP/acarologia/ acarologia@supagro.inra.fr Acarologia is under free license and distributed under the terms of the Creative Commons-BY-NC-ND which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original author and source are credited. The digitalization of Acarologia papers prior to 2000 was supported by Agropolis Fondation under the reference ID 1500-024 through the « Investissements d'avenir » programme (Labex Agro: ANR-10-LABX-0001-01) Acarologia 53(3): 347–348 (2013) Water mites of the genus Unionicola (Hydrachnidia: Unionicolidae) are symbionts of freshwater mol-lusks and sponges, occurring on every continent ex-cept Antarctica. In part of their lifecycle the mites themselves are parasites of chironomids, while the mussels depend for their reproduction on fishes. Dale Edwards and Malcolm Vidrine spent a lifelong scientific career studying these mites. The first pub-lication of Vidrine appeared as far back as 1973, the first publication of Edwards in 1988. All known in-formation on these mites is now summarized in a self-published book. The 9 chapters deal with top-ics like biogeography, classification, mussel-mite in-teractions, coevolution and phylogenetics. Eight of the chapters present a lot of existing material, but the chapter on phylogenetic relationships provides a lot of new information. The book ends with seven appendices, where all information on the known species and subgenera of Unionicola can be found, as well as a list of the known higher taxa of freshwa-ter mussels, snails and sponges which are known as host for Unionicola mites. Three genera are known as symbionts of freshwater molluscs, e.g. Dockov-dia, Najadicola and Unionicola. The former two gen-era are symbionts of snails in Africa and freshwa-ter mollusks in Asia, respectively, but they do not belong to the Unionicolidae. The freshwater fauna of North American mussels is extremely rich. Not only in number of species but sometimes in num-ber of specimens as well. Mussels are occasionally so abundant that they form reefs, comparable with coral reefs. Unfortunately, freshwater mussels and their reefs are endangered and threatened in North America by changes in hydrology and pollution, which affect their mites also. The subgeneric classification of the genus Union-icola has been altered considerably by the publica-tions of these authors, especially by the publica-tions of Vidrine. Karl Viets (1956) and later on Cook (1974) discerned eight subgenera, but the number of subgenera now tallies an astonishing 57 subgenera. Mitchell (1965) noted that oviposition sites within mussels are limited, and that varied mites have dis-tinctive genital fields that are adapted for oviposi-tion in varied tissues. This led Vidrine to use the genital fields for subgeneric classification in a large number of papers. However, this subgeneric classi-fication has led to debate among acarologists.