These appear to match some figures we have seen of Heliacus dorsuosus. However, the World Register of Marine Species lists H. dorsuosus as a synonym of H. implexus, while gastropods.com lists it as a synonym of Heliacus variegatus. Certainly, ours does look like it could be a H. variegatus with the black faded to brown. Our specimens were empty and in about 10m of water on the seaward reef.
Created 25 June 2019