This is the first part of a series of books dealing with the free-living nematodes of Hungary. Following different introductory chapters, the first volume deals with the orders Monhysterida, Araeolaimida and Chromadorida of the class Torquentia, furthermore with the order Rhabditida of the class Secernentia. Lists of references and registers of families, genera and species are drawn up for each volume.
The higher taxonomic units (classes, orders, suborders) containing free-living (= non-animal parasitic) continental nematodes are discussed in detail and commented on from a taxonomic point of view. All the families comprising terrestrial and/or freshwater genera are keyed and diagnosed. As a next step, all non-marine genera of these families are enumerated, either in the form of keys if they have not yet been recorded from Hungary, or in detail if they have Hungarian representatives. World lists of the valid species belonging to the latter genera are provided, as well as keys to Hungarian species. Finally, each free-living nematode species observed to date in Hungary is presented.
Of the class Torquentia 104 species belonging to 35 genera and of the class Secernentia 153 species belonging to 69 genera (altogether 257 species of 104 genera) are discussed in the present volume.
Originally, the intention was to include illustrations of each Hungarian species, but to prevent the volume from becoming too large, only a selected species of each genus is illustrated.