AppearanceThe shells of these quite common cowries reach on average 65–70 millimetres of length, with a minimum size of 50 millimetres and a maximum size of 120 millimetres . They are egg-shaped . The surface of the shell is smooth, shiny and completely snow white, with a dark reddish-purple interior, visible through the wide and long aperture, which bears teeth on one side only. In the living cowries the mantle is black, with a pattern of small white spots in adults, while juveniles resemble some toxic nudibranchs of the genus ''Phyllidia'' owing to their orange yellow sensorial papillae. The lateral flaps of the mantle usually hide completely the white surface, but the mantle is quickly retracted into the shell opening when the cowry is disturbed.
DistributionThis species is distributed in the Red Sea and in the Indian Ocean along East Africa and in Western and Central Pacific Ocean .
Habitat''Ovula ovum'' lives in tropical reef in shallow waters at 2–20 metres of depth, usually on algae or soft corals, mainly feeding on Alcyonarian colonies .
Some text fragments are auto parsed from Wikipedia.