Synopsis of the species of Myxidium Butschli, 1882 (Myxozoa: Myxosporea: Bivalvulida)

A synopsis of the species of Myxidium Butschli, 1882 (Myxozoa: Myxosporea: Bivalvulida) is presented. It includes a total of 232 nominal species, whose principal morphological and morphometric characteristics, site of infection within the host, and original hosts and locality are indicated in a tabulated format. A diagrammatic illustration of a spore of most of the species is also provided.