Sepia insignis is a species of cuttlefish native to the southwestern Indian Ocean, specifically South Africa, from the Cape of Good Hope to Natal. It lives at depths to42 m. S. insignis grows to a mantle length of 60 mm. The type specimens, consisting solely of cuttlebones, were collected on Tongaat Beach, KwaZulu-Natal, South Africa (29°35′S 31°07′E / 29.583°S 31.117°E). They are deposited at The Natural History Museum in London.