This species was described from Cap l'Abeille, near Banyuls-sur-Mer, France.
It has been reported from the bay of Gallipoli, Italy,[2] in the Mediterranean Sea and around the southern African coast on the Atlantic side of the Cape Peninsula in 10–15 m of water.
Atagema rugosa is described as a beige animal, darker in the lower parts of the mantle.
It has five gills, with the three posterior held almost horizontal and the two anterior very small.
[1] The South African rugby-ball dorid is a small white nudibranch with black spots, a warty skin and a distinct longitudinal ridge down the middle of its back.