Abstract
A new species of calycophoran siphonophore, Sphaeronectes pagesi sp. nov., is described from material collected in Sagami Bay, Japan. The taxonomic affinities of the other Sphaeronectes species known from Japanese waters are discussed. For S. fragilis, which is reported for the first time from the North Pacific, and S. koellikeri new photographs of the living animals and line drawings are provided.