A new pontoniine shrimp (Crustacea: Decapoda: Palaemonidae) from the Ryukyu Islands,Japan

An unusual new genus and species of pontoniine shrimp, Nippontonia minirostris gen. nov., sp. nov., from a sponge host from the Ryukyu Is., Japan, is described and illustrated. The new genus appears not to be closely related to any of the previously described genera. The genus is particularly remarkable for the morphology of the fixed finger of the minor second pereiopod, which is without parallel in the Palaemonidae.