ABSTRACT

The Tetranychidae (Actinedida or Prostigmata) include species that are the most important plant-feeding mite pests of agriculture around the world, attacking food crops, trees, and ornamentals (Jeppson et al. 1975, Meyer 1981, Hussey and Scopes 1985, Zhang and Liang 1997, Bolland et al. 1998, Zhang 2003). Outbreaks of spider mites can cause serious yield losses and even death of the crop plant. About 1250 species are known to feed on 3877 different plants, although only about 100 species are considered economically important. The number of species is unclear because the taxonomy of this group is not fully resolved, and additional species may be discovered in new habitats. Some species probably include cryptic species. A relative few species (e.g., Tetranychus urticae, T. cinnabarinus, T. pacicus, T. kanzawai, Panonychus ulmi, P. citri, Oligonychus punicae, O. coffeae, Eutetranychus orientalis) are considered major pests in multiple locations and on multiple crops. The most notorious of all is the two-spotted spider mite (Tetranychus urticae), which has a worldwide distribution (Figure 6.1).