Ingo Arndt / Blue Crab (Discoplax hirtipes) with claws raised in defensive / aggressive posture, endemic to Christmas Island, Indian Ocean, Australian Territory

Ingo Arndt / Blue Crab (Discoplax hirtipes) with claws raised in defensive / aggressive posture, endemic to Christmas Island, Indian Ocean, Australian Territory

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...

Pete Oxford / Blue Land Crab (Cardisoma guanhumi) male, Banco Chinchorro, Yucatan Peninsula, Mexico

Ingo Arndt / Blue Crab (Discoplax hirtipes) in defensive posture, Christmas Island, Indian Ocean, Territory of Australia

Martin Gabriel / Mangrove crab (Cardisoma carnifex) , Curieuse Island, Republic of Seychelles

Roland Seitre / Red Claw Crab (Cardisoma carnifex) Gossanah, Ouvea, Loyalty Islands Province, New Caledonia.

Claudio Contreras / Blue Land Crab (Cardisoma guanhumi), Sian Ka'an Biosphere Reserve, Yucatan Peninsula, Mexico, August.

Claudio Contreras / Blue Land Crab (Cardisoma guanhumi), Sian Ka'an Biosphere Reserve, Yucatan Peninsula, Mexico, August.

Stephen Belcher / Christmas Island Red Crab (Gecarcoidea natalis) and Blue Crab (Discoplax hirtipes) carcasses, death caused by Yellow Crazy Ants (Anoplolepis gracilipes), Christmas Island National Park, Christmas Isla...

Stephen Belcher / Christmas Island Red Crab (Gecarcoidea natalis) and Blue Crab (Discoplax hirtipes) carcasses, death caused by Yellow Crazy Ants (Anoplolepis gracilipes), Christmas Island National Park, Christmas Isla...

Charlie Summers / Cocos Purple Land Crab (Cardisoma carnifex) in defensive position. Cocos-Keeling Island, Indian Ocean, Australia, May.