I found this species in a variety of habitats around Oahu and at Puako, Hawaii, from under rocks on intertidal reefs to caves and ledges at night at depths to about 20m. But they were most common along the Magic Island channel on Oahu. This area usually had low visibility and silty conditions due to rainfall, which drained out of the valleys above Honolulu into the Ala Wai canal and then emptied into the ocean through this channel. But it was a rich area for filter feeders and their predators, including various species of nudibranchs. However, the area was subject to considerable stress due to the changing condition. The fauna in this area has reportedly changed drastically since the time I was observing it in the late 1970s.
The specimen below was observed on the seaward reef of Kure Atoll out at the end of the northwestern Hawaiian Islands.
Created 20 April 2009
Updated 1 July 2012