
Fish or Mollusk?
A sea slug that lives in open water, looks and swims like a fish, and glows in the dark? That is Phylliroe bucephala, a transparent, bioluminescent, three inches-long nudibranch gastropod. The sea slug swims in the upper layers of the open ocean, throughout the world’s tropical and subtropical regions. This great image above, by black-water diver and photographer Linda Ianniello, shows the sea slug feeding on a small jellyfish, possibly an Aequorea species. (Zoom in, and you can see three amphip