Vexillum subdivisum  Vexillum (Vexillum) subdivisum, common name : the Costate Mitre, is a species of small sea snail, marine gastropod mollusk in the family Costellariidae, the ribbed miters. The shell size varies between 30 mm and 60 mm This species is distributed in the Indian Ocean along Mauritius and in the Pacific Ocean along Australia, Papua New Guinea and Okinawa.