Karyotypes of Parasitic Hymenoptera

This summary of the results of chromosomal analysis of various groups of parasitic wasps will be essential reading for those working in the field. It is the second edition of a monograph that was first published in Russian, and has been substantially updated with new data, conclusions and references.

The goal of this ground-breaking work is to document the author's study of the karyotype structure and chromosomal evolution of parasitic Hymenoptera. It also interprets the results obtained, from both routine and differential chromosome staining, for systematic and phylogenetic purposes.

Despite the huge importance of parasitic wasps, many problems of their taxonomy remain insufficiently studied. This is a situation that needs rectifying, as Hymenoptera are one of the largest and most taxonomically complicated groups of insects and they play a very important role in food chains as parasitoids of the overwhelming majority of insects and other arthropods. Parasitic wasps attack many pests of agriculture and forestry as well as certain beneficial insects. In addition, some secondarily phytophagous Hymenoptera damage certain cultivated plants.

The renowned entomologist and author of this volume, Vladimir Gokhman, has himself developed a particular technique for obtaining chromosomal preparations from adult parasitic wasps. This allowed the inclusion of a wide range of those insects into the study.

The karyotypic features of the majority of superfamilies and families as well as many lower taxa of parasitic Hymenoptera are listed, while the plesiomorphic and apomorphic character states of chromosome sets of parasitic wasps are revealed.

The structural features of karyotypes used for identifying and discriminating sibling species and similar forms are shown, as are the data on chromosome sets of about 400 species of parasitic Hymenoptera (including more than 200 micrographs). Also included is a comprehensive phylogenetic and taxonomicanalysis of karyotypic information.

This book is unique because it demonstrates a range of karyotypic data for an insect group that seemed unattainable in this respect not so long ago. Rich in new facts, techniques and ideas, it will be of use to all those interested in karyology and Hymenoptera.

Auteur

Dr. Vladimir E. Gokhman is a leading researcher and the head of the Plant Protection Group of the Botanical Garden of Moscow State University, Moscow, Russia. He works at the Botanical Garden since 1983, after graduating with honour from the MSU Department of Entomology. Dr. Gokhman's main research interests are karyology and systematics of parasitic wasps. He has defended a PhD ("Karyology and systematics of the subfamily Ichneumoninae (Hymenoptera, Ichneumonidae"; Moscow State University, 1990) and a Doctor of Science (DSc) thesis ("Karyotypes of parasitic Hymenoptera: their evolution and implications for systematics and phylogeny"; Zoological Institute of the Russian Academy of Sciences, 2003). Dr. Gokhman is a member of the editorial board of the Russian Entomological Journal and also a member of the International Society of Hymenopterists and the Russian Entomological Society.

Résumé
Not so long ago, karyology was considered a vanguard biological discipline, which could solve nearly all problems of systematics and phylogenetics. We liked to believe in the bright future, in a magician who will appear like a Jack-in-the-box and reveal the truth to us. However, excessive hopes related to the chromosomal study came true only in part. In the meantime, new candidates claimed the place of the magician, i. e. phenetics succeeded by cladistics and now by molecular methods in systematics and phylogeny. Nevertheless, it becomes progressively more ob- ous nowadays that cladistics is just a bright envelope for the fairly primitive and theoretically vulnerable approach that deprives living organisms and their groups of the traces of integrity and reduces them to the plain sum of characters. Modern molecular techniques look more perceptive and may yield more reliable results, although the details are sometimes embarrassing, and comparison with the fossil record does not necessarily reveal their superiority over cladistics. These methods are accessible by research teams with massive funding and good equipment and this strongly decreases the range and diversity of the material studied. However, classi?cations are often created by individual systematists with the restricted access to molecular methods. In this context, karyological techniques are in the preferable position, although they certainly do not provide direct and immaculate markers of taxonomic and p- logenetic relationships: chromosomal study is a morphological method with all its advantages and drawbacks.

Contenu
Chromosomes of Hymenoptera.- Material and Methods.- Morphological Features of Karyotypes of Parasitic Hymenoptera.- Chromosomal Evolution of Parasitic Wasps.- Phylogenetic Implications of Karyotypic Characters of Parasitic Hymenoptera.- Chromosomal Analysis of Parasitic Wasps at Various Taxonomic Levels.