Georgette Douwma / Nudibranch (Chromodoris willani) with a scale worm. Lembeh Strait, North Sulawesi, Indonesia.

Alex Mustard / Nudibranchs (Doto greenamyeri) newly described species on feather hydroids. Seraya Bay, north coast of Bali, Indonesia. Java Sea.

Alex Mustard / Portrait of a Nudibranch (Flabellina pellucida) on a kelp frond with star trails. Gulen, Norway. North East Atlantic Ocean.

Alex Mustard / Nudibranch (Flabellina lineata) in aquarium, taken in the field in Gulen, Norway. North East Atlantic Ocean. Collected for scientific research.

Alex Mustard / Nudibranch (Nembrotha cristata) climbing on a Tunicate (Polycarpa aurata) at night. This species of seaslug feeds on seasquirts. A tiny cyclopoid copepod swimming past. Yillet Yecil, Yillet Islands, M...

Constantinos Petrinos / Chromodorid nudibranch (Chromodoris annae) on Sea Squirt (Polycarpa aurata) Lembeh Strait, North Sulawesi, Indonesia.

Alex Mustard / Emperor shrimp (Periclimenes imperator / Zenopontonia rex) hitchhiking on large t-bar nudibranch (Ceratosoma trilobatum) The shrimp gains food source and protection on the toxic seaslug. Bitung, North...

Franco Banfi / Nudibranch (Cratena peregrina) on a sponge, Ist Island, Croatia, Adriatic Sea, Mediterranean.

Franco Banfi / Nudibranch (Janolus cristatus) Vela Luka, Korcula Island, Croatia, Adriatic Sea, Mediterranean

Franco Banfi / Nudibranch (Flabellina affinis) Vela Luka, Korcula Island, Croatia, Adriatic Sea, Mediterranean.

Jeff Rotman / Symbiotic emperor shrimp (Periclimenes imperator / Zenopontonia rex) living in the gills of a spanish nudibranch (Hexabranchus sanguineus) Red Sea, Egypt

Alex Mustard,Alex Mustard / A nudibranch (Dendronotus frondosus) photographed in the field aquarium, Gulen, Norway. North East Atlantic.

Alex Mustard,Alex Mustard / Nudibranch (Flabellina nobilis) photographed in the field aquarium in Gulen, Norway. North East Atlantic Ocean.

Alex Mustard,Alex Mustard / A nudibranch (Flabellina nobilis) feeding on a solitary hydroid (Tubularia indivisa), note how the hydroid is bent back as it is pulled into the nudibranch's mouth. Gulen, Bergen, Norway. North East A...

Alex Mustard,Alex Mustard / A portrait of a nudibranch ( Limacia clavigera) searching for food on algae. Gulen, Norway. North East Atlantic Ocean.

Alex Mustard / 2020VISION / Nudibranch (Limacia clavigera) feeding on Sea matt bryozoan, growing on kelp frond, Shetland Islands, Scotland, UK, June

Alex Mustard / 2020VISION / Nudibranch eggs (Tritonia hombergi) Loch Carron, Ross and Cromarty, Scotland, UK, April

Alex Mustard / 2020VISION / Nudibranch (Polycera quadrilineata) portrait on a kelp frond, Island of Coll, Inner Hebrides, Scotland, UK, June.

Alex Mustard / 2020VISION / Nudibranch (Polycera quadrilineata) feeding on sea mat (bryozoan) growing on kelp frond. Shetland Islands, Scotland, UK. June.

Alex Mustard / 2020VISION / White nudibranch (Eubranchus farrani) on kelp frond, Lunna Kirk, Shetland Islands, Scotland, UK, June

Juergen Freund / Detail of Nudibranch (Dendrodoris tuberculosa) Batangas, Philippines.

Juergen Freund / Nudibranch (Jorunna funebris) feeding on its preferred sponge, Kimbe Bay, West New Britain, Papua New Guinea

Hiroya Minakuchi / Kunie's Chromodorid Nudibranch (Chromodoris kuniei), Borneo, Malaysia

Hiroya Minakuchi / Nudibranch (Hypselodoris bullockii) pair mating, Borneo, Malaysia

Juergen Freund / Chromodoris nudibranch (Cadlinella sp.) Lembeh Strait, North Sulawesi, Indonesia.

Wild Wonders of Europe / Lundgren / Gibraltar nudibranch (Tambja ceutae) Pico, Azores, Portugal, July 2009

Wild Wonders of Europe / Sá / Nudibranch, Deserta Grande, Desertas Islands, Madeira, Portugal, August 2009

Wild Wonders of Europe / Banfi / Nudibranch eggs, Larvotto Marine Reserve, Monaco, Mediterranean Sea, July 2009

Wild Wonders of Europe / Banfi / Nudibranch (Flabellina affinis) on algae (Caulerpa taxifolia) Larvotto Marine Reserve, Monaco, Mediterranean Sea, July 2009

Wild Wonders of Europe / Lundgren / Nudibranchs (Onchidoris muricata) on Kelp leaf, Moere coastline, Norway, February 2009

Wild Wonders of Europe / Lundgren / Nudibranch (Adalaria proxima) egg laying, Moere coastline, Norway, February 2009

Wild Wonders of Europe / Lundgren / Nudibranch (Polycera quadrilineata) on Kelp leaf, Moere coastline, Norway, February 2009 WWE BOOK PLATE. Wild Wonders kids book.

Wild Wonders of Europe / Lundgren / Nudibranch (Dendronotus frondosus) on a Kelp leaf, Moere coastline, Norway, February 2009

Wild Wonders of Europe / Lundgre / Nudibranch (Polycera quadrilineata) Lofoten, Norway, November 2008

Wild Wonders of Europe / Lundgren / Nudibranch (Flabellina lineata) on seaweed, Saltstraumen, Bod, Norway, October 2008

Wild Wonders of Europe / Pitkin / Nudibranch / Sea slug (Discodoris / Peltodoris atromaculata) feeding on a sponge (Petrosia ficiformis) Cala di Grecu, Lavezzi Islands, Corsica, France, September 2008

Wild Wonders of Europe / Lundgren / Nudibranch (Flabellina verrucosa) on seaweed, Saltstraumen, Bod, Norway, October 2008

Wild Wonders of Europe / Lundgren / Three Nudibranchs (Polycera quadrilineata) on Kelp encrusted with Sea-mat / Lacy crust bryozoan (Membranipora membranacea) Saltstraumen, Bod, Norway, October 2008

Wild Wonders of Europe / Lundgren / Nudibranch (Flabellina verrucosa) on seaweed, Saltstraumen, Bod, Norway, October 2008

Birgitte Wilms / Nudibranch laying eggs, Indonesia

Jeff Rotman / Emperor Shrimp (Periclimenes imperator / Zenopontonia rex) living inside gills of Spanish Dancer Nudibranch (Hexabranchus sanguineus). Egypt, Red Sea.

Juergen Freund / White lined / Alabaster nudibranch or Falling archangel {Dirona albolineata} Canada, Pacific

Doug Perrine / Dorid nudibranch {Nembrotha kubaryana} feeding on tunicates, Borneo

Solvin Zankl / Nudibranch {Flabellina rubrolineata} Lembeh Strait, Indonesia

Solvin Zankl / Nudibranch {Polycera quadrilineata} Lembeh Strait, Indonesia

Solvin Zankl / Nudibranch {Chromodoris sp} Lembeh Strait, Indonesia

Solvin Zankl / Nudibranch {Nembrotha purpureolineolata} Lembeh Strait, Indonesia

Norbert Wu / Nudibranch (Chromodoris sp) breathes through gills on back, Borneo

Fred Bavendam / Giant Nudibranch (Dendronotus iris) attacking a Tube-dwelling Anemone (Pachycerianthus fimbriatus), Vancouver Island, British Columbia, Canada. Sequence 4 of 5

Pascal Kobeh / Sea slug or nudibranch (Ardeadoris / Glossodoris cruenta) New Caledonia, Pacific Ocean.

Alex Mustard / Nudibranch (Nembrotha milleri) on the seabed. Dauin, Dauin Marine Protected Area, Dumaguete, Negros, Philippines. Bohol Sea, tropical west Pacific Ocean.

Alex Mustard / Emperor shrimp (Zenopontonia rex) female rides on the back of a nudirbranch (Tambja morosa), while picking food from the seabed. Anilao, Batangas marine protected area, Luzon, Philippines. Verde Islan...

Alex Mustard / Pair of Emperor shrimp (Zenopontonia rex / Periclimenes imperator) female is the larger one, hitch a ride on a large nudibranch (Tambja luteolineata) and pick food from the seabed with their claws. Bi...

Sergio Hanquet / Nudibranch (Flabellina affinis). Canary Islands, Tenerife.

David Hall / Sea slug (Melibe viridis) with oral hood for sifting sand in search of prey. Komodo, Indonesia.

David Hall / Halgerda nudibranch (Halgerda batangas). Komodo, Indonesia.

Pascal Kobeh / Nudibranch (Thecacera sp) pair prior to mating. Flores Sea, Indonesia.

Doug Perrine / Spanish dancer nudibranch (Hexabranchus sanguineus) defecating whilst swimming. Gato Island, off Malapascua, Cebu, Philippines.

Magnus Lundgren / Wild Wonders of China / Butterfly nudibranch (Cyerce elegans) Xiaoliuqiu Island, Taiwan

Magnus Lundgren / Wild Wonders of China / Free swimming juvenile spanish dancer (Hexabranchus sanguineus) in the night, Kenting National Park, Hengchun Peninsula, Taiwan

Magnus Lundgren / Wild Wonders of China / Free swimming juvenile spanish dancer (Hexabranchus sanguineus) in the night, Kenting National Park, Hengchun Peninsula, Taiwan

Magnus Lundgren / Wild Wonders of China / Bullock's hypselodoris (Hypselodoris bullockii) Xiaoliuqiu Island, Taiwan

Magnus Lundgren / Wild Wonders of China / Caramel nudibranch (Glossodoris rufomarginata) . Xiaoliuqiu Island, Taiwan

Magnus Lundgren / Wild Wonders of China / Dorid nudibranch (Hypselodoris maculosa) Kenting National Park, Hengchun Peninsula, Taiwan

Magnus Lundgren / Wild Wonders of China / Dorid nudibranch (Chromodoris strigata) feedings on sponges. Kenting National Park, Hengchun Peninsula, Taiwan

Magnus Lundgren / Wild Wonders of China / Dorid nudibranch (Glossodoris cincta) Kenting National Park, Hengchun Peninsula, Taiwan

Gary Bell/ Oceanwide / Nudibranch (Ceratosoma sp) with commensal Emperor Shrimp (Periclimenes imperator), Philippines

Gary Bell/ Oceanwide / Nudibranch (Ceratosoma sp) with commensal Emperor Shrimp (Periclimenes imperator), Philippines

Gary Bell/ Oceanwide / Dorid Nudibranch (Phyllidia varicosa), Anilao, Philippines

Gary Bell/ Oceanwide / Nudibranch (Phyllodesmium serratum), Port Phillip Bay, Mornington Peninsula, Victoria, Australia

Gary Bell/ Oceanwide / Tyron's Risbecia (Risbecia tryoni) with commensal Emperor Shrimp (Periclimenes imperator), Milne Bay, Papua New Guinea

Gary Bell/ Oceanwide / Tyron's Risbecia (Risbecia tryoni) with commensal Emperor Shrimp (Periclimenes imperator), Milne Bay, Papua New Guinea

Gary Bell/ Oceanwide / Nudibranch (Goniobranchus kuniei), Anilao, Philippines

Gary Bell/ Oceanwide / Nudibranch (Phyllodesmium longicirrum), Philippines

Gary Bell/ Oceanwide / Nudibranch (Chromodoris bullocki), Bali, Indonesia

Pascal Kobeh / Dotted sea slug (Peltodoris atromaculata), Canary Islands

Pascal Kobeh / Mediterranean / Pink flabellina nudibranch(Flabellina affinis), Canary Islands

Pascal Kobeh / Nudibranch / sea slug giant doris (Hypselodoris picta), Canary Islands

Pascal Kobeh / Anna's chromodoris nudibranchs (Chromodoris annae) courtship, Sulu sea, Philippines

Pascal Kobeh / Anna's chromodoris nudibranchs (Chromodoris annae) courtship, Sulu sea, Philippines

Pascal Kobeh / Lined Thuridilla / Orange-edged sapsucking nudibranch / sea slug (Thuridilla lineolata), Sulu sea, Philippines

Pascal Kobeh / Leopard chromodoris nudibranch (Goniobranchus / Chromodoris leopardus), Sulu sea, Philippines

Pascal Kobeh / Purple-spotted hypselodoris nudibranch (Hypselodoris purpureomaculosa), Sulu sea, Philippines

Pascal Kobeh / Miller's Nembrotha nudibranch / sea slug (Nembrotha milleri) feeding on a colony of ascidians / tunicates (Clavelina sp.), Sulu sea, Philippines

Pascal Kobeh / Giant doris nudibranch (Hypselodoris picta) on the sandy bottom, Canary Islands

Shane Gross / Nudibranch (Dondice occidentalis) feeding on algae in a land locked alakaline lagoon on Eleuthera, Bahamas.

Alex Mustard / Portrait of a colourful nudibranch (Chromodoris annae). Bitung, North Sulawesi, Indonesia. Lembeh Strait, Molucca Sea.

Georgette Douwma / Nudibranch - Flatworm Discodoris (Discodoris boholiensis). Lembeh Strait, North Sulawesi, Indonesia.

Georgette Douwma / Solar-powered phyllodesmium (Phyllodesmium longicirrum) this species has evolved a symbiotic relationship with zooxanthellae. Lembeh Strait, North Sulawesi, Indonesia.

Georgette Douwma / Nudibranch (Cuthona yamasui) Lembeh Strait, North Sulawesi, Indonesia.

Georgette Douwma / Nudibranch (Janolus savinkini) Lembeh Strat, North Sulawesi, Indonesia.

SCOTLAND: The Big Picture / Lined polycera (Polycera quadrilineata) nudibranch feeding on a kelp (Mebranipora membranacea) frond, Sula Sgeir, Scotland, UK, February.

SCOTLAND: The Big Picture / Painted balloon aeolis (Eubranchus tricolor) feeding on bryozoan, Loch Carron, Scotland, UK, January.

SCOTLAND: The Big Picture / Four lined nudibranch (Polycera quadrilineata) feeding on a bryzoan mat (Mebranipora membranacea) Scotland, UK, January.

SCOTLAND: The Big Picture / Nudibranch on tunicate (Coryphella sp.), Shetland Isles, Scotland.

Georgette Douwma / Nudibranch (Phyllidia ocellata) West Papua, Indonesia. Indo-West Pacific.