Sepia hieronis is a species of cuttlefish that grows to a mantle length of 70 mm and can be found in the Great Chagos Bank.
Sepia hieronis is a species of cuttlefish native to the southeastern Atlantic Ocean and southwestern Indian Ocean, specifically southern Namibia, from approximately 27S to Port Alfred, South Africa, and east Africa from 17S to Kenya and Mozambique. It is also present in the Saya-de-Malha Bank. 
