The species of the genus Excirolana (Isopod), which are intertidal species inhabiting the surficial sediments of sandy beach, are found throughout the world’s oceans. Recently, it has been clarified that the geophysical environment represented by suction

Studies on the intertidal sand-beach isopod, Excirolana chiltoni, have shown the species to be ovoviviparous. Large yolk-filled eggs are deposited into paired uteri of the female where they remain throughout gestation. Intrauterine development progresses

Descriptions are given of Cirolana coronata sp. nov., Eurydice nipponica sp. nov., and C. harfordi japonica from deep water, sand, and rocky shore habitats respectively in Japan. Excirolana japonica, E. kincaidi, and E. vancouverensis, are considered