Species list
     North Atlantic
     South Atlantic
     Central Pacific
     Western Pacific
     South Pacific
     New Zealand
     Indian Ocean
     Red Sea
Eastern Pacific
     North America
     Central America
     South America


The number of sites devoted to the study and appreciation of sea slugs seems to grow exponentially. So, it's impossible to include them all. However, in the following list we've attempted to provide links to most of those that offer major galleries of photos and/or extensive information. Please let us know if we've made errors, particularly for the non-English sites (we're not sure about the authors or titles in some cases due to the problematic nature of Google translations...).

For sites that deal with broader topics, we've usually included links to both the home page and the opisthobranch section as a convenience. Also, sites that deal with a broader geographic area aren't repeated under each of the subdivisions of that region.

Internal links to the major regions are provided at the left for the convenience of the user.



    Anthony's Nudibranchs by Anthony Holley
    Bibliographia Nudibranchia by Gary McDonald
    Circolo Attivitŕ Subacquee Chieri (opisthobranchs)
    Dive Rosa by Rokus Groeneveld & Sanne Reijs (opisthobranchs)
    Doris by Muséum national d'Histoire naturelle
    e-Opisthobranchia by Nestor Ardila
    Hardy's Internet Guide to Marine Gastropods  by Eddie Hardy
    ID Please Facebook group by Kati Eschweiler
    Linda Ianniello
    Mediterranean Opisthobranchs (with world links) by Erwin Koehler
    Marine Life by Rafi Amar (opisthobranchs)
    Nudibase Facebook group by Marli Wakeling
    Nudibranch Central Facebook group by Gary Cobb
    Nudibranch Domain by David Mullins
    Nudibranchs by Jim Anderson
    Nudibranchs of the World by Marli Wakeling
    Nudibranchs, Worms and Sea Slugs Facebook group by Dan Ledesma
    Nudibranch Systematic Index by Gary McDonald
    Pelagic Molluscs by S. van der Spoel, L. J. Newman & K. W. Estep (on-line version)
    Sea Slug Forum by Bill Rudman
    Sea Slugs of the World by iNaturalist
    Sea Slug World by Ocean Blue
    Shark Cage by Gordon Smith (opisthobranchs)
    Slug Site by Michael D. Miller
    The Best Nudibranch Hunter by Danny Van Belle & Caroline De Tandt
    Tropical Reefs by Florent Charpin (opisthobranchs)
    Umiushi-zukan by K. Akasaka
    Vibrant Sea by Jeffrey Rosenfeld (opisthobranchs)
    World Registry of Marine Species
    Worldwide Food Habits of Nudibranchs by Gary McDonald


North Atlantic

    Canadian opisthobranchs by Yann Querrec (opisthobranchs)
    Hypselodoris by Joăo Pedro Silva
    Nudibranchs of the British Isles by Bernard Picton
    Opisthobranchs from the Azores by Peter Wirtz
    Opisthobranchs from the Canary Islands by Peter Wirtz
    Opisthobranchs from the Cape Verde Islands by Peter Wirtz
    OPK-Opisthobranchs by Manuel Ballesteros, Enric Madrenas & Miquel Pontes (opisthobranchs)
    Scottish Nudibranchs by Jim Anderson
    Sea and Coastline (opisthobranchs)
    The Marine Flora & Fauna of Norway by Kĺre Telnes (opisthobranchs)


    Jaxonville Shells by Bill Frank (opisthobranchs)
    Seaslugs Guadeloupe
    SE Florida Sea Slugs by Linda Ianniello (opisthobranchs)

    Atlas of Exotic Molluscs in the Mediterranean by CIESM
    Conchiglie del Mediterraneo by Guido & Marco Arduino (opisthobranchs)
    Grup de Recerca d'Opistobranquis de Catalunya (GROC) by Research Group of Catalonia opisthobranchs (opisthobranchs)
    Mare Nostrum by Miquel Pontes (opisthobranchs)
    Opisthobranchs of the Coast of Granada by Luis Sánchez Tocino
    OPK-Opistobranquis by Manuel Ballesteros, Enric Madrenas & Miquel Pontes (opisthobranchs)

South Atlantic



    Fishpics Hawaii by Keoki and Yuko Stender (opisthobranchs)
    Hawaiian list from the Slug Site by Michael D. Miller
    Hawaiian Sea Slugs by Scott Johnson
    Hawaii's Fishes by John Hoover (opisthobranchs)
    HURL Deep-sea Animals
    Joe Weston Photography by Joe Weston (opisthobranchs)
    Kawaihae Reef  by Hai Van On (opisthobranchs)
    Marine Life et cetera by Karolle Wall (opisthobranchs)
    My Hawaiian Images by James Petruzzi (opisthobranchs)
    Ocean Arts Hawaii by Glenn Poulain (opisthobranchs)
    Photos by Barry Fackler (opisthobranchs)
    Sea Life Images by Jerry Kane (opisthobranchs)
    Sea Slugs of Hawaii Facebook group by Alex Dutcher, Kyle Pias & April McCormack
    Spanglers' Scuba by Randall Spangler (opisthobranchs)
    The Odyssey of Dai Mar by Dai Mar Tamarack & Heidi Miller (opisthobranchs)
    Underwater Imaging by Cynthia Hankins
    Wild Insights by David Rolla (opisthobranchs)


    Creatures of Awazi Island (opisthobranchs)
    Croissant Island, Okinawa (opisthobranchs)
    Float Island Umiushi by Sunset Resort
    Izu Umiushi by Izuzuki Diver (opisthobranchs)
    Japanese Nudibranchs by Shigeki Ikegami
    Light and Dark by Yukinobu Adachi (opisthobranchs)
    Nissie's Photo Albums by Nissie (opisthobranchs)
    Okinawa Fish (opisthobranchs)
    Okinawa Nature Photography by Shawn Miller (opisthobranchs)
    Opisthobranchs of the Kii peninsula by Yasuhiro Shirai
    Sea Slug of the Japan Sea Coasts of Middle Japan by Takaoka Biological Club (opisthobranchs)
    Ukishima Nudibranchs by N.& Y. Friend
    Umiushi by Jun Imamoto
    Umiushi Facebook group
Central Pacific

    Kwajalein Underwater by Scott & Jeanette Johnson

Western Pacific

    Amateur Branching by Patrik Good (opisthobranchs)
    Biodiversity of Singapore (opisthobranchs)
    Fauna and Flora of New Caledonia (opisthobranchs)
    Fauna and Underwater Flora of New Caledonia (opisthobranchs)
    Guam Marine Life by Dave Burdick (opisthobranchs)
    Guam Mollusks by Bob Abela
    Happy Nudibranch by Fran Roberts & Nevar Fourie
    LJAX Photography by Larry L. Jackson (opisthobranchs)
    Macronesia by Shane Siers (opisthobranchs)
    Marine Research at Museum Victoria (opisthobranchs)
    Nudibranch Field Guide by Downbelow UK
    Nudibranchs by Roberto Sozzani
    Nudibranchs of Southwest Australia by Matthias Liffers
    Nudibranchs of the Philippine Islands by Jeffrey Jeffords
    Nudibranchs of the Sunshine Coast, Australia by Gary Cobb & David Mullins
    Port Philip Marine Life by Museum Victoria  (opisthobranchs)
    Sea Slugs in Saipan by Hiramushi
    Sea Slugs of the Tweed-Byron Coast, Australia by Denis Riek (opisthobranchs)
    Solitary Islands Research Group (opisthobranchs)
    Starfish by Teresa Zubi (opisthobranchs)
    Underwater Critters by Christian Knost (opisthobranchs)
    Underwater Photo Gallery by David Harasti (opisthobranchs)
    Wet Image Photography by Phil Woodhead (opisthobranchs)
    Wild Singapore by Ria Tan (opisthobranchs)

South Pacific

    TahitiNudi by Pauline Bosserelle & Fabien Michenet
New Zealand

    Beautiful seaslugs of New Zealand by J. Floor Anthoni
    New Zealand Molluscs by Andrew Spurgeon
    New Zealand Nudibranchs by Ian Skipworth (opisthobranchs)
    New Zealand Seashore by Rod Morris (opisthobranchs)
Indian Ocean

  Reunion Island Mollusks by Philibert Bidgrain (opisthobranchs)

Red Sea

    Invertebrates of the Gulf of Eilat by Jacob Dafni (opisthobranchs)
    Opisthobranchs of the Red Sea by Oren Lederman

Eastern Pacific

North America

     California Sea Slugs by I-Naturalist
     Intertidal Invertebrates of the Monterey Bay Area, California by Gary McDonald
     La Jolla Shores Nudibranchs by Steve Gardner
     Metridium Fields by Clinton Bauder
     Morro Bay Underwater by Ken Bondy & Gary Powell (opisthobranchs)
     Ocean Light by Philip Cola (opisthobranchs)
     Pacific Northwest Shell Club (opisthobranchs)
     Sea Slugs by Jan Kocian
     Southern California Nudibranch ID Guide by Scott Penny

Central America

South America


Underwater Field Guide to Ross Island & McMurdo Sound, Antarctica by Peter Brueggeman (opisthobranchs)
Species list