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.

Ingo Arndt / Christmas Island Red Crabs (Gecarcoidea natalis) massing on coastal rocks, the morning after spawning, Christmas Island, Indian Ocean, Australian Territory

Ingo Arndt / Christmas Island Red Crabs (Gecarcoidea natalis) shortly before sunrise sitting on rock ready for spawning, Christmas Island, Indian Ocean, Australian Territory

Tui De Roy / Dead Sally-lightfoot crab (Grapsus grapsus) washed up in surf, Puerto Egas, James Bay, Santiago Island, Galapagos, Ecuador, May.

Linda Pitkin / 2020VISION / Spiny spider crab (Maja brachydactyla / squinado) pair on rock covered with red algae, Lundy Island Marine Conservation Zone, Devon, England, UK, May.

Christophe Courteau / Edible crab in tide pool split level {Cancer pagurus} Brittany France

Fabio Liverani / Freshwater Crab (Potamon fluviatile) brandishing claws in defensive posture. Foreste Casentinesi National Park, Italy, July.

Wild Wonders of Europe / Quinta / Marbled rock crab (Pachygrapsus marmoratus) portrait, Alentejo, Natural Park of South West Alentejano and Costa Vicentina, Portugal, June 2009

Wild Wonders of Europe / Quinta / Crab (Eriphia verrucosa) on rock, Alentejo, Natural Park of South West Alentejano and Costa Vicentina, Portugal, June 2009

Pascal Kobeh / Atlantic / Common rock crab (Cancer irroratus) on the reef in the middle of green sea urchins (Strongylocentrotus droebachiensis) Gulf of Saint Lawrence, Canada

Pascal Kobeh / Atlantic rock crab or common rock crab (Cancer irroratus) on the reef, Gulf of Saint Lawrence, Canada.

Nick Upton / Young Edible crab (Cancer pagurus) and a Rock goby (Gobius paganellus) side by side in a rock pool, looking towards the camera, The Gower, Wales, UK, August.