Rick Price / Flame fiddler crab (Uca flammula), two males displaying and fighting with sword-like pincers. Cyclone Creek, Talbot Bay, The Kimberley

Heather Angel / Land crab crawling on red sandstone after overnight storm. Shunan Zhuhai National Park, Sichuan Province, China.

Shane Gross / Channel clinging crab (Mithrax spinosissimus), Eleuthera, Bahamas.

Remi Masson / Japanese mud crab (Macrophthalmus japonicus) feeding in mud, reflected in water. Kyushu Island, Japan. August.

Remi Masson / Crab (Uca sp) with large pincer, in mud. Kyushu Island, Japan. August.

Nick Upton / Velvet swimming crab (Necora puber) in rockpool. Near Falmouth, Cornwall, England, UK. September.

Nick Upton / Squat lobster (Galathea squamifera) in rockpool. South Devon, England, UK. September.

Nick Upton / Edible crab (Cancer pagurus) from Atlantic Ocean. Cornwall, England, UK. September.

Nick Upton / Velvet swimming crab (Necora puber) from English Channel. South Devon, England, UK. September.

Nick Upton / Squat lobster (Galathea squamifera) from English Channel. South Devon, England, UK. September.

David Fleetham / Splendid round crab (Etisus splendidus) holding pieces of coral that it has broken off with its lobed claws. Philippines.

Ernie Janes / Common earwig (Forficula auricularia) close up of pincers