For the great majority of the species, the data were taken from the original descriptions. When this was not possible, alternative sources were used, as indicated in the table. Species not sufficiently characterised, and therefore not permitting comparison with other species, were not incorporated into the list. These include M. unicapsulatus (Gurley, 1893), M. mugilis (Perugia, 1891), M. merlucii (Perugia, 1891) and M. musculi Keisselitz, 1908.