Hirano in Hirano & Ito, 1998
Closeup of head on upper left showing characteristic 2 lines which give it is name. Compare with photo on lower right of Facelina quadrilineata with 4 lines. PHOTOS: Yoshi Hirano.
One distinguishing feature of this species is the pair of brown to bright orange-red lines on the head.
It has been found during most of the year at Kominato, Boso Peninsula, Honshu Island, from the low intertidal to shallow sublittoral. It is often found in close association with the athecate hydroid Eudendrium sp., but in laboratory feeding experiments at least 6 other species of hydroids were ingested as well - Hirano & Ito, 1998.
Refer to the page on Facelina quadrilineata for a discussion of anatomical differences, and see the page comparing the development of the two very similarly coloured sympatric species Facelina bilineata and Facelina quadrilineata.
• Ito, M. & Hirano, Y. (1996) the spawn and embryonic development of two colour morphs of the aeolid nudibranch Facelinella quadrilineata(Baba, 1930). Venus, 55(2): 115-121.
• Hirano, Y.J. & Ito, M. (1998). 'Facelinella quadrilineata' (Baba, 1930), a pair of cryptic species of Facelina from Japan. Zoological Science, 15: 791-797.
Rudman, W.B., 1999 (June 26) Facelina bilineata Hirano in Hirano & Ito, 1998. [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/factsheet/facebile