A New Genus and Five New Species of Kalyptorhynchia (Platyhelminthes: Rhabdocoela) Discovered in Northern Japan

抄録

We have described a new genus and five new species of free-living marine flatworms in Schizorhynchia (Platyhelminthes: Rhabdocoela: Kalyptorhynchia) based on the material collected from sandy intertidal zones around Hokkaido, Northern Japan. These include Freddius tricaudatus gen. et sp. nov. (Cheliplanidae) and Proschizorhynchella caudociliata sp. nov., P. magnoliae sp. nov., P. shibazakii sp. nov., and P. shuttlecock sp. nov. (Schizorhynchidae). Based on this study, the number of confirmed species in the suborder Kalyptorhynchia discovered in Japanese waters has increased from one to six. Freddius tricaudatus gen. et sp. nov. possesses proboscis hooks that are so peculiar among Cheliplanidae that they warrant the establishment of a new genus.