Phylliroe bucephala is a parasitic species of pelagic nudibranch, a marine gastropod mollusc in the family Phylliroidae.
Biology This species of nudibranch is transparent with its guts visible through the laterally flattened body. It has a tail and two long smooth rhinophores. It feeds on jellyfish and plankton as an adult. The juveniles parasitize Zanclea medusae.Gosliner TM, Valdes A Behrens DW 2015 Nudibranch and Sea Slug Identification Indo-Pacific New World Publications Jacksonville Florida USA
References
Powell A. W. B., New Zealand Mollusca, William Collins Publishers Ltd, Auckland, New Zealand 1979 SeaSlugForum