I saw only a few of these in Hawaii, all associated with Caulerpa algae. The individual figured below was found at night at Makua, Oahu, exposed on Caulerpa at a depth of about 6m in September, 1984. The presence of irregular bluish lines on the animal beneath the transparent shell is the easiest way to distinguish them from the similar Lobiger viridis we find a bit more often in the Marshall Islands.It is possible they all are variants of the same species.
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Slugs of Hawaii
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Marshall Islands Sea Slugs
Created 20 April 2009
Updated 17 May 2012