Cerithiopsis ioCerithiopsis io is a species of sea snail, a gastropod in the family Cerithiopsidae, which is known from the Caribbean Sea and the Gulf of Mexico. It was described by Dall and Paul Bartsch in 1911.DescriptionThe maximum recorded shell length is 2.3 mm.HabitatMinimum recorded depth is 5.4 m. Maximum recorded depth is 6 m.