抄録
Pisulinella is proposed as a new monotypic genus in the neritopsine family Neritiliidae, with the single species Pisulinella miocenica sp. nov. This new taxon occurs in subsurface Miocene sediments from Eniwetok Atoll, Marshall Islands, western Pacific. Nine specimens of P. miocenica were previously regarded as close to Nerita (Amphinerita) polita Linnaeus of the Neritidae. Reallocation of this species from Neritidae to Neritiliidae is based mainly on the shape of the protoconch, which is conspicuously tilted relative to the teleoconch whorls and has several spiral ridges. The discovery of this neritiliid species, previously allocated to the Neritidae, suggests that detailed examination of protoconchs is necessary for defining the systematic position of fossil neritopsines. Pisulinella miocenica sp. nov. may have lived in a cryptic habitat.