Juergen Freund / Arrow crab on sponge (Stenorhynchus seticornis) Caribbean

Juergen Freund / Arrow crab on brain coral {Stenorhynchus seticornis} Caribbean Sea, Cuba

Shane Gross / Arrow crab (Stenorhynchus seticornis) on coral. Eleuthera, Bahamas.

Pascal Kobeh / Yellowline arrow crab (Stenorhynchus seticornis / lanceolatus), Canary Islands

Graham Eaton / Yellowline Arrow Crab (Stenorhynchus seticomis) in an Azure Vase Sponge (Callyspongia plicifera). St Lucia, West Indies, July.

Michele Westmorland / Spotted Moray Eel (Gymnothorax moringua) with mouth open, and Arrow crab (Stenorhynchus seticornis) in healthy coral reef system, Dominica, West Indies, Caribbean.

Michele Westmorland / Spotted Moray Eel (Gymnothorax moringua) with mouth open, and Arrow crab (Stenorhynchus seticornis) in healthy coral reef system, Dominica, West Indies, Caribbean.

Chris Newbert / Arrow Crab (Stenorhynchus seticornis) in Anemone (Heteractis sp) 60 feet deep, Caribbean

Doug Perrine / Diver photographs Arrow crab {Stenorhynchus seticornis} on spnge, St Croix, Caribbean

Norbert Wu / Arrow Crab (Stenorhynchus seticornis) long spindly arms around central arrow-shaped body, Caribbean

Constantinos Petrinos / Spotted moray eel {Gymnothorax moringua} and spider crab {Stenorhynchus seticornis} Bonaire, Caribbean

Juergen Freund / Arrow crab (Stenorhynchus seticornis) on fan coral. Caribbean

Roberto Rinaldi / Arrow crab (Stenorhynchus setircornis), Belize

Roberto Rinaldi / Arrow crab (Stenorhynchus setircornis), Belize.

Angelo Giampiccolo / Arrow crab (Stenorhynchus seticornis) on tube sponge at night, Belize Cayes, Caribbean.

Angelo Giampiccolo / Arrow crab (Stenorhynchus seticornis) in tube sponge at night, Belize Cayes, Caribbean.

Angelo Giampiccolo / Arrow crab (Stenorhynchus seticornis) on a tube sponge at night, Belize Cayes, Caribbean.

Angelo Giampiccolo / Arrow crab (Stenorhynchus setircornis) on tube sponge, at night in the Belize Cayos, Caribbean.

Angelo Giampiccolo / Arrow crab (Stenorhynchus seticornis) in a tube sponge at night, Belize Cayes, Caribbean.

Angelo Giampiccolo / Arrow crab (Stenorhynchus seticornis) inside tube sponge at night, Belize Cayes, Caribbean.

Roberto Rinaldi / Yellowline arrow crab (Stenorhynchus seticornis), on white gorgonian sea fan / lace sea fan (Eunicella singularis), Cayos Cochinos, Honduras.

Alex Mustard / Arrow crab (Stenorhynchus seticornis) resting in its home inside a Brown tube sponge (Agelas conifera), Grand Cayman, Cayman Islands, Caribbean Sea.

David Hall / Yellowline arrow crab (Stenorhynchus seticornis) feeding on an unidentified segmented worm, probably a polychaete tube worm (Sabellidae), Dominica, Caribbean, Western Atlantic Ocean.

David Hall / Yellowline arrow crab (Stenorhynchus seticornis) living in association with Giant Caribbean sea anemone (Condylactis gigantea), Dominica, Caribbean.

Claudio Contreras / Yellowline arrow crab (Stenorhynchus seticornis), Cozumel Island, Caribbean Sea, Mexico.

Claudio Contreras / Yellowline arrow crab (Stenorhynchus seticornis), Cozumel Island, Caribbean Sea, Mexico.

Claudio Contreras / Yellowline arrow crab (Stenorhynchus seticornis) with featherstar, Cienaga de Zapata National Park, Matanzas Province, Cuba.

Robert Pickett / Arrow Crab (Stenorhynchus seticornis) occurs in Atlantic Ocean, captive.