Superbly camouflaged crab on Playa Guiones beach, Nosara, Nicoya Peninsula, Guanacaste Province, Costa Rica, Central America

Hairy hermit crab (Aniculus elegans), Southern Thailand, Andaman Sea, Indian Ocean, Southeast Asia, Asia

Hairy hermit crab (Aniculus elegans), Southern Thailand, Andaman Sea, Indian Ocean, Southeast Asia, Asia

Hairy squat lobster (Lauriea siagiani) amongst a pink and orange colored sponge, Tulamben, Bali, Indonesia, Southeast Asia, Asia

Hairy hermit crab (Aniculus elegans), SouthernThailand, Andaman Sea, Indian Ocean, Southeast Asia, Asia

Orang Utan Spider Crab, Achaeus japonicus, Ambon, Moluccas, Indonesia

Crab eyes, Dominica, West Indies, Caribbean, Central America

Spider Crab covered with Anemones, Cyclocoeloma tuberculata, Ambon, Moluccas, Indonesia

Small Sponge Crab, Dromia dormia, Kai Islands, Moluccas, Indonesia

Pink hairy squat lobster (Lauriea siagiani) inside a pink barrel sponge, Lembeh Strait, Bitung, North Sulawesi, Indonesia.

Goby with a hermit crab, Australia.

A Caribbean reef octopus (Octopus briareus) explores the seafloor of a shallow reef off the coast of Belize. This intelligent cephalpod ranges throughout the Caribbean feeding on lobster, crab, and small fish.

A decorator crab camouflages himself by attaching living sponges and anemones, Sabah, Borneo, Malaysia, Southeast Asia, Asia

Decorator crab (Cyclocoeloma tuberculata). Indo Pacific

Coleman Shrimp (Periclimenes Colemani) Zebra or Urchin Crab (Zebrida adamssi) on Fire Urchin (Asthenosoma varium). Lembeh Strait, Sulawesi, Indonesia

Brown Swimming Crab (Liocarcinus navigator), clear view of crab showing colour and shell markings, St Abbs, Scotland, UK North Sea

Xeno or Black Coral Crab, (Xenocarcinus conicus) on Sea Fan. Lembeh Strait, Sulawesi, Indonesia

Tiny Ghost Crab hinding in Bubble coral. Thailand.

Tiger Snake Eel - Myrichthys tigrinus - burrowing amongst bottom debris, in this image can be seen with a small crab in it's mouth. Galapagos, Pacific Ocean

Arrow crab on gorgonian. Indo Pacific

Shore crab at Drumbeg in Assynt, Scotland, United Kingdom, Europe

Brown Swimming Crab (Liocarcinus navigator), clear view of crab showing colour and shell markings, St Abbs, Scotland, UK North Sea

Brown Swimming Crab (Liocarcinus navigator), clear view of crab showing colour and shell markings, St Abbs, Scotland, UK North Sea

Shore crab at Drumbeg in Assynt, Scotland, United Kingdom, Europe

Crab spider (Thomisus onustus), which uses its forelegs to capture any insect seeking to pollinate the flower, lurking in a blossom, Frejus, Fréjus, Var, France, Europe

Bug-eye Squat Lobster (Neomunida olivarae), also known as a colored squat lobster or the google-eyed fairy crab, Dumaguete, Philippines

A Slender Spongegoby (Phyllogobius platycephalops) and two different species of crabs. Attached to the goby are several parasites with egg cases, that will likely prove fatal over time. Many species live on the convuluted surface of this sponge, Philippin

Both a Crinoid Commensal Shrimp (Periclimenes cornutus) and a Crinoid Squat Lobster (Allogalathea elegans) on a crinoid. These tiny crustaceans are commensal on crinoids or feather stars and take their color from the host, Philippines

This soft coral crab or candy crab (Hoplophrys oatesii), is wearing a decoration of soft coral polyps on top of head as camouflage, Dumaguete, Philippines

Two Crab-eye goby, Signigobius biocellatus, Papua New Guinea, Neu Britannien, New Britain

Commensal Shrimp in Coral Polyps, Periclimenes psamathe, Raja Ampat, West Papua, Indonesia