ABSTRACT
Members of the genus Rickettsiella are responsible for a number of diseases in invertebrates. The Œrst Rickettsiella disease was reported from larvae of the Japanese beetle Popillia japonica (Dutky and Gooden 1952). This deadly disease was called blue disease due to the discoloration of the insect larvae. Since then Rickettsiella diseases have been described from insects of the orders Lepidoptera, Orthoptera, Diptera, Dictyoptera, Coleoptera, Hymenoptera, and Hemiptera, as well as from arachnids and crustaceans (Table 7.1).
