Three females belonging to this species were obtained from the branchial cavity of Microcosmus exasperatus at Spanish Water, Curaçao, April 3, 1920. They were not fully grown but measured about 4.50 mm in length, and the large incubatory pouch was filled with minute eggs. This is the species described by THORELL and referred by him to the genus Doropygus, but it differs so much from the other species of that genus that both GIESBRECHT and SARS recognized it as generically distinct. GIESBRECHT referred it to COSTA’S genus Notopterophorus, and SARS created for it the new genus named above, which seems to be correct.