Marionia rubra

Image courtesy of Susan Byrne
Photo taken at Julian Rocks Northern NSW Australia
Canon G 12 camera in an Ikelite housing with Inon Z240 strobes

Marionia rubra (Ruppell & Leuckart, 1828)

Wow - what spectacular shots by Sue Byrne! Members of the family Tritoniidae are characterized by having paired secondary gill branches and rhinophores with a crown of papillae surrounding finger-like apices. All members are specialized predators on octocorals, including soft corals, gorgonians and sea pens.

Tritonia and Marionia are differentiated by internal characters. Marionia has stomach plates in the digestive system, which are lacking in Tritonia. Some species like Marionia rubra, here, have dorsal tubercles on the notum.

M. rubra varies greatly in color from deep red as we see in Sue's photos to light green or brown. Opaque white pigment covers the body. It has 8-12 short velar appendages with multiple tips. The margins of the rhinophoral sheaths are broad and undulating as you can clearly see in Sue's photo above.

This species may be found on page 323 of Nudibranch and Sea Slug Identification: and is certainly on our wish list for the Nudibranch Workshop in Anilao, Philippines in March. Join us.

Super find Susan!

Dave Behrens
Sammamish, WA 98074
Jan., 2016
Send Dave email at


Walter Marti is the kind of videographer I aspire to be was gracious enough to allow posting of a series of short video clips based on workshops hosted at Crystal Blue Resort the past couple of years. Two of these submissions made the cut for our 16th annual Film Exhibition in San Diego last October. Walter excels in Macro and if thats where you want to be as a uw photographer/videographer, you are invited to view his videos for a sneak peak at the wonderful underwater world of Anilao, Philippines

Odd Critters Doing Interesting Things
Hiding and Finding in Anilao

Bonnie/Walter's Anilao Photo/Video Workshop 2015
Anilao CritterFest 2015
Anilao-October 2014
CritterFest 2013 Anilao Philippines

Susan's images are a great way to bring in the New Year! In fact I can't think of a better way! Let us all hope 2016 brings peace and prospertiy and renewed opportunities to explore the wonderful world of our friends, the Sea Slugs!

Michael Miller
San Diego, Calif
Jan. 2016

Susan Byrne

My name is Susan Byrne I live at Lennox Head NSW Australia. I am retired and have logged over 4,500 dives, Divemaster/Dive Guide for Sundive Byron Bay. I have dives all around Australia from Cairns Qld to Broome W.A. Overseas I have dived Kavieng, Kimbe Bay, Witu Islands & Fathers Reefs in P.N.G, Uepi, Gizo, Munda & Honiara in the Solomon Islands, Santo & Vila in Vanuatu, Taveuni & Beqa Island in Fiji, Palau, Truk Lagoon, Dauin & Cabilao in the Philippines.

Send Susan mail at

From left to right, Terry Gosliner, Angel Valdes, Dave Behrens La Jolla, Calif.

Send Dave email at

© The Slug Site, Michael D. Miller 2016. All Rights Reserved.