Hypermastus orstomiHypermastus orstomi is a species of sea snail, a marine gastropod mollusk in the family Eulimidae.DistributionThe shell of Hypermastus orstomi reaches a length of approximately 6 mm. Like other members of the Eulimidae family, it exhibits a slender and elongated shape, adapted for its parasitic lifestyle.This marine species occurs off New Caledonia.Habitat and distributionThis species is found in marine environments off New Caledonia. It is known to be parasitic on irregular sea urchins, a characteristic trait of many eulimid gastropods.