Claudio Contreras / Bluehead Wrasse (Thalassoma bifasciatum) juvenile cleaning Smooth Trunkfish (Lactophrys triqueter), Banco Chinchorro Biosphere Reserve, Caribbean region, Mexico, May

Shane Gross / Two grey triggerfish (Balistes capriscus) fight over a large piece of plastic floating at the surface among sargassum seaweed (Sargassum natans) in the Sargasso Sea, Atlantic Ocean.

Nick Hawkins / Ocean sunfish (Mola mola) off Halifax, Nova Scotia, Canada. July.

Georgette Douwma / Thornback cowfish (Lactoria fornasini). Lembeh Strait, North Sulawesi, Indonesia.

Georgette Douwma / Taylor's pygmy leatherjacket (Brachaluteres taylori). Lembeh Strait, North Sulawesi, Indonesia.

Jurgen Freund / Globefish (Diodon nicthemerus) swimming past a mass of plastic moving in the current, North Sulawesi, Indonesia.

David Fleetham / Smooth trunkfish (Lactophrys triqueter), portrait. Bonaire, Dutch Caribbean.

Alex Mustard / Colourful reef scene with Coral grouper (Cephalopholis miniata), map puffer (Arothron mappa) and Panda butterflyfish (Chaetodon adiergastos). Tank Reef, Fiabacet Islands, Misool, Raja Ampat, Indonesia...

Georgette Douwma / Blue triggerfish (Pseudobalistes fuscus). Egypt, Red Sea. Indo-Pacific.

Solvin Zankl / Porcupinefish (Diodontidae) tiny juvenile, found in plankton community, Sargasso Sea, Bermuda.

Sue Daly / Ocean sunfish (Mola mola) , Sark, British Channel Islands, UK, September.

Franco Banfi,Franco Banfi / Ocean Sunfish (Mola Mola) with Longfinned bannerfish (Heniochus acuminatus) Crystal Bay, Nusa Penida, Bali Island, Indonesia, Pacific Ocean

Magnus Lundgren / Wild Wonders of China / Clown triggerfish (Balistoides conspicillum) Green Island, Taiwan.

Magnus Lundgren / Wild Wonders of China / Juvenile yellow boxfish (Ostracion cubicus) Green Island, Taiwan.

Shane Gross / Yellowmargin triggerfish (Pseudobalistes flavimarginatus) feeding in Tapegrass (Halophila stipulacea) seagrass bed. Marsa Alam, Egypt.

Claudio Contreras / Caribbean sharpnose puffer (Canthigaster rostrata), Cozumel Island, Caribbean Sea, Mexico.

Claudio Contreras / Caribbean sharpnose puffer (Canthigaster rostrata), Cozumel Island, Caribbean Sea, Mexico.

Claudio Contreras / Slender Filefish (Monacanthus tuckeri) juvenile hiding in gorgonian), Xkalac Reefs National Park, Caribbean region, Mexico, May

Claudio Contreras / Spotted trunkfish (Lactophrys bicaudalis), Xkalac Reefs National Park, Caribbean region, Mexico, May

Claudio Contreras / Long-spine porcupinefish (Diodon holocanthus), Xkalac Reefs National Park, Caribbean region, Mexico, May

Claudio Contreras / Caribbean sharpnose puffer (Canthigaster rostrata) and Great Star Coral (Montastraea cavernosa), Banco Chinchorro Biosphere Reserve, Caribbean region, Mexico.

Claudio Contreras / Smooth trunkfish (Lactophrys triqueter), Banco Chinchorro Biosphere Reserve, Caribbean region, Mexico.

Alex Mustard / School of Oriental sweetlips (Plectorhinchus vittatus) gather tightly together as they rest during the day, with a Clown triggerfish (Balistoides conspicillum) and Midnight snappers (Macolor macularis...

Alex Mustard / Portrait of Porcupinefish (Diodon hystrix). East End, Grand Cayman, Cayman Islands, British West Indies. Caribbean Sea.

Alex Mustard / RF - Portrait of Orange-lined triggerfish (Balistapus undulatus) on a coral reef. Tulamben, Bali, Indonesia. Java Sea. (This image may be licensed either as rights managed or royalty free.)

Sirachai Arunrugstitchai / Starry puffer (Arothron stellatus) is seen floating at the surface after being discarded as bycatch from a commercial purse seiner, Andaman Sea, Thailand, Krabi Province, Thailand, December 2015.

Sirachai Arunrugstitchai / Longhorn cowfish (Lactoria cornuta) juvenile foraging for food along the seafloor during the night, Lembeh Strait, North Sulawesi, Indonesia.

Sirachai Arunrugstitchai / Longhorn cowfish (Lactoria cornuta) swimming in the dark water during the night, Lembeh Strait, North Sulawesi, Indonesia.

Sirachai Arunrugstitchai / Shortspine Porcupinefish (Cyclichthys orbicularis) on sandy bottom at night, Lembeh Strait, North Sulawesi, Indonesia.7.

Alex Mustard / Eye and fin detail of a scrawled filefish (Aluterus scriptus) on a coral reef. Arborek Island, Raja Ampat, West Papua, Indonesia. Dampier Strait. Ceram Sea. Tropical West Pacific Ocean.

Alex Mustard / Slender filefish (Monacanthus tuckeri) hiding in the branches of a porous sea rod (Pseudoplexaura sp.) on a coral reef. Jardines de la Reina, Gardens of the Queen National Park, Cuba. Caribbean Sea.

Georgette Douwma / Thornback cowfish (Lactoria formasini). Lembeh Strait, North Sulawesi, Indonesia.

Georgette Douwma / Juvenile map puffer (Arothron mappa). Lembeh Strait, North Sulawesi, Indonesia.

Magnus Lundgren / Large filefish (Monacanthidae) hanging on to a Rhizostomae jellyfish, Balayan Bay, off Anilao, Batangas, Philippines, Pacific Ocean.

Magnus Lundgren / Rare and previously unseen behavior with an adult blackspotted puffer (Arothron nigropunctatus) swimming around with a dead younger fish of the same species in its beak-like mouth. Nightdive close to...

Magnus Lundgren / Rare and previously unseen behavior with an adult blackspotted puffer (Arothron nigropunctatus) Balayan Bay from Anilao, Mabini, Batangas, the Philippines.

Brandon Cole / Picasso triggerfish (Rhinecanthus assasi), Egypt, Red Sea. Endemic.

Brandon Cole / Black triggerfish (Melichthys niger), also called Black Durgon. Baja, Mexico, Pacific Ocean.

Brandon Cole / Guineafowl puffer (Arothron meleagris), changing colour between black and golden phases. Baja, Mexico, Pacific Ocean.

Brandon Cole / Spotfin burrfish (Chilomycterus reticulatus). Baja, Mexico, Pacific Ocean.

Brandon Cole / Yellow boxfish (Ostracion cubicus), intermediate adult phase. Palau, Pacific Ocean.

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) playing with pufferfish, Mosquera Islet, Galapagos.

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) playing with puffer fish, Mosquera Islet, Galapagos.

Magnus Lundgren / Filefish, (Monacanthidae) holding on to a jellyfish using the stinging cells of the jelly to protect itself. Balayan Bay, off Anilao, Batangas, Philippines, Pacific Ocean Magnus

Magnus Lundgren / Filefish (Monacanthidae) holding on to a jellyfish using the stinging cells of the jelly to protect itself. Balayan Bay, off Anilao, Batangas, Philippines, Pacific Ocean. Magnus

Sergio Hanquet / Bandtail puffer (Sphoeroides marmoratus) hunting amongst Little neptune seagrass (Cymodocea nodosa) Tenerife, Canary Islands.

Sergio Hanquet / Bandtail puffer (Sphoeroides marmoratus) Tenerife, Canary Islands.

Claudio Contreras / Buffalo trunkfish (Lactophrys trigonus) in front of Elkhorn coral (Acropora palmata),Jardines de la Reina / Gardens of the Queen National Park, Caribbean Sea, Ciego de Avila, Cuba.