The opalfish (Hemerocoetes monopterygius; ) is a ray-finned fish of the genus Hemerocoetes, found only around New Zealand, at depths of between . Their length is between .
Gallery
References
Tony Ayling & Geoffrey Cox, Collins Guide to the Sea Fishes of New Zealand, (William Collins Publishers Ltd, Auckland, New Zealand 1982) Wade Doak, A Photographic Guide to Sea Fishes of New Zealand, (New Holland Publishers (NZ) Ltd, Auckland, New Zealand 2003)