When Franklin published her book on cyst nematodes in 1951, the cyst nematodes were already known as serious pests of brassicas, cereals, potatoes and sugar beets. However, at that time this group of nematode, with about 12 species, was considered tobe largely temperate in distribu tion. Now a total of 105 species (including those that are considered as synonyms or species inquirende by some or all) within six genera of cyst nematodes have been described from temperate, tropical, and subtropical regions and at least five species are important constraints to crop produc tion in tropical...