New records of semiaquatic species Marionina (Clitellata, Enchytraeidae) from Japan, with a description of Marionina biwaensis sp. nov.

Marionina biwaensis sp. nov. is described from Lake Biwa. This new species differs from all other Marionina species: lacking lateral chaetae completely and ventral chaetae in II, segment number 38-43, origin of dorsal blood vessel XV or XVI, spermathecal ampullae with irregular protuberances and chaetal distribution 1 per postclitellar bundles. In addition, the descriptions of M. coatesae, M. nevisensis, and M. riparia are augmented and recorded here for the first time in Japan.

New records of semiaquatic species Marionina (Clitellata, Enchytraeidae) from Japan, with a description of Marionina biwaensis sp. nov.

Marionina biwaensis sp. nov. is described from Lake Biwa. This new species differs from all other Marionina species: lacking lateral chaetae completely and ventral chaetae in II, segment number 38-43, origin of dorsal blood vessel XV or XVI, spermathecal ampullae with irregular protuberances and chaetal distribution 1 per postclitellar bundles. In addition, the descriptions of M. coatesae, M. nevisensis, and M. riparia are augmented and recorded here for the first time in Japan.