Fred Olivier / Watchman goby (Cryptocentrus cinctus) and alpheid shrimp mutualism, the goby keeps watch while the shrimps dig and clean a shared burrow in the sand, Uepi Island, Solomon Islands.
Fred Olivier / Tawny hermit crab (Coenobita rugosus) emerging from its shell, Christmas Island, Indian Ocean, Australian Territory.
Alex Mustard / Commensal emperor shrimp (Periclimenes imperator) moves across the colourful red patterned surface of its host Candycane sea cucumber (Thelenota rubralineata). Misool, Raja Ampat, West Papua, Indonesi...
Alex Mustard / Reef lizardifsh (Synodus variegatus) at a cleaning station, being cleaned by Holthuis anemone shrimps (Ancylomenes holthuisi). Bitung, North Sulawesi, Indonesia. Lembeh Strait, Molucca Sea.
John Chan / Crenulated fiddler crab (Uca crenulata) waving its major claw at another crab, part of a courtship display, Southern California, USA, June.
John Chan / Crenulated fiddler crab (Uca crenulata) feeding on detritus, Southern California, USA, June.
John Shaw / Sally lightfoot crabs (Grapsus grapsus) on the beach at Puerto Egas, Santiago Island, Galapagos, May.
Nick Hawkins / European green crab (Carcinus maenas), an invasive species in North America, Kejimkujik Seaside National Park, Nova Scotia, Canada. July.
SCOTLAND: The Big Picture / Close up of a Long clawed squat lobster (Munida rugosa) in Loch Carron, January 2016.
Georgette Douwma / Boxer Crab (Lybia tessellata) with sea anemones in its claws for defense. Lembeh Strait, North Sulawesi, Indonesia.
Juergen Freund / Wide-angle timelapse of Sand bubbler crabs (Dotillidae) feeding, filtering detritus and plankton from sand and discarding the processed sand as pellets, which cover the beach, Wet Tropics World Herita...
Juergen Freund / Sand bubbler crabs (Dotillidae) feeding, filtering detritus and plankton from sand and discarding the processed sand as pellets, which cover the beach, Wet Tropics World Heritage Area, Cape Tribulatio...
Juergen Freund / Sand bubbler crab (Dotillidae) feeding, filtering detritus and plankton from sand and discarding the processed sand as pellets, which cover the beach, Wet Tropics World Heritage Area, Cape Tribulation...
Andy Rouse / Sally lightfoot crab, (Grapsus grapsus), feeding on marine iguana parasites and dead skin, Galapagos
Steven David Miller / Sand bubble patterns created by Sand bubbler crabs (Scopimera inflata), Cape Hillsborough National Park, Queensland, Australia. September.
Solvin Zankl / Bioluminescent Sea-fireflies (Vargula hilgendorfii) producing a bright blue light. The light is produced by mixing two chemicals together in the presence of oxygen and is for mating displays or defenc...
Remi Masson / European crayfish (Astacus astacus) in a lake. Alps, Switzerland, July.
David Fleetham / Cleaner wrasse (Labroides dimidiatus) eating parasites off Coral grouper (Cephalopholis miniata) with Shrimp (Lysmata amboinensis) Mabul Island, Malaysia.
Tony Wu / Humpback whale (Megaptera novaeangliae) adult female at rest. The tubercles on the whale's head are clearly visible, as are the barnacles (Coronula diadema), whale lice (Cyamus boopis), and hairs on t...
Doc White / California sea otter (Enhydra lutris) feeding on Northern kelp crab, Monterey Bay, California, USA, Eastern Pacific Ocean, May
Jan Hamrsky / Brine shrimp or monkey shrimp (Artemia salina) female. Controlled conditions.
Adrian Davies / Blackback land crab (Gecarcinus lateralis) dragging leaf into burrow, Barbados.
Jeff Rotman / Hauling in dragger net filled with Haddock (Melanogrammus aeglefinus), Pollock (Pollachius), Dogfish (Squalidae) and Lobster (Nephropidae) Georges Bank off Massachusetts, New England, USA, May 2015. M...
Juergen Freund / Mud crab (Scylla serrata) in shallow sandy water. Split level with island and thatched house on stilts. Moromahu Island, Wakatobi, South Sulawesi, Indonesia. Second Place in the Portfolio Award of the...
Alex Mustard / Portrait of Sally lightfoot crab (Grapsus grapsus) on a beach. San Cristobal Island, Galapagos Islands, Ecuador. Tropical East Pacific Ocean.
Alex Mustard / Red eye medusa (Polyorchis penicillatus) with hitchhiking amphipods (Hyperia medusarum). Browning Pass, Vancouver Island, British Columbia, Canada. North East Pacific Ocean.
Solvin Zankl / Deepsea Isopod (Glyptonotus antarcticus) from Antarctic Ocean at a depth of 231m.
Tui De Roy / Dead Sally-lightfoot crab (Grapsus grapsus) washed up in surf, Puerto Egas, James Bay, Santiago Island, Galapagos, Ecuador, May.
Nick Upton / Common prawns (Palaemon serratus) and a Rock goby (Gobius paganellus) feeding on a dead Montagu's crab (Xantho hydrophilus) in a rockpool, Cornwall, England, UK, September.
Nick Upton / Rock goby (Gobius paganellus) stealing food from a scavenging Common prawn (Palaemon serratus) in a rockpool, Cornwall, England, UK, September.
Constantinos Petrinos / Peacock-tail anemone shrimp (Periclimenes brevicarpalis) living commensally with the Branching Sea Anemone (Actinodendron glomeratum). Lembeh Strait, North Sulawesi, Indonesia.
Olga Kamenskaya / Amphipod (Acanthogammarus victorii), Lake Baikal, Russia. June.