Jurgen Freund / Sea apple (Pseudocolochirus violaceus) with tentacles exposed, feeding, Komodo NP, Indonesia, Indo-pacific.

Jurgen Freund / Eyed / Leopard sea cucumber (Bohadschia argus), close-up of the skin. Lembeh Strait, North Sulawesi, Indonesia.

David Shale / Deepsea benthic Sea cucumber (Peniagone sp) with commensal polynoid polychaete, from mid atlantic ridge, depth approx 2600m, June 2010

David Shale / Deepsea benthic Sea cucumber (Peniagone porcella) from mid atlantic ridge, depth approx 2500m, June 2010

Jeff Rotman / Scarlet Psolus Sea Cucumber (Psolus fabricii), feeding with arm in mouth. Bay of Fundy, Canada, Atlantic Ocean.

Georgette Douwma / Burrowing sea cucumber (Neothyonidium magnum). The massive tentacular crown is the only part that is visible, the rest is buried in the sand. Feeds by picking particles out of the water with the tenta...

Franco Banfi / Sea cucumber (Holothuria edulis) Maldives, Indian Ocean

Jurgen Freund / Sea cucumbers {Thelonota anax} on sandy sea floor. Great Barrier Reef, Queensland, Australia

Jurgen Freund / Sea cucumbers {Thelonota anax} on sandy sea floor. Great Barrier Reef, Queensland, Australia

Jurgen Freund / Various sea cucumbers including (Thelonota anax) on sandy sea floor. Sea cucumber in foreground, Great Barrier Reef, Queensland, Australia

Georgette Douwma / Edible sea cucumber (Holothuria edulis) one of the edible species of sea cucumbers served as 'sea slugs', 'trepang' or 'Beche de mer'. Maldives, Indian Ocean

Georgette Douwma / Graeff's sea cucumber (Bohadschia graeffei) has climbed on top of a coral boulder to spawn, Andaman Sea, Thailand

Georgette Douwma / Graeff's sea cucumber (Bohadschia graeffei) has climbed on top of a coral boulder to spawn, Andaman Sea, Thailand

Georgette Douwma / Graeff's sea cucumber (Bohadschia graeffei) has climbed on top of a coral boulder to spawn, Andaman Sea, Thailand

Georgette Douwma / Graeff's sea cucumber (Bohadschia graeffei) Andaman Sea, Thailand.

Georgette Douwma / Sea cucumber (Thelenota anax) defecating. The most massive holothurian in the Indo-Pacific, reaching 1 meter in length. Andaman Sea, Thailand.

Georgette Douwma / Sea cucumber (Synaptula sp.) crawling on (Thelenota rubralineata) Manado, North Sulawesi, Indonesia

Georgette Douwma / Edible sea cucumber (Holothuria edulis) extruding sand, Manado, North Sulawesi, Indonesia

Georgette Douwma / Synaptid sea cucumber (Holothuroidea) on sponge, Rinca, Komodo National Park, Indonesia

Georgette Douwma / Yellow sea cucumber (Colochirus robustus) feeding, Rinca, Komodo National Park, Indonesia

Georgette Douwma / Pacific sea apple (Pseudocolochirus violaceus) closed up, Komodo National Park, Indonesia

Alex Mustard / Donkey dung sea cucumber (Holothuria mexicana) lifting its head up from the sand to spawn in late afternoon, East End, Grand Cayman, Cayman Islands, British West Indies, Caribbean Sea.

David Shale / Deepsea Sea cucumber (Holothuroidea) from Dragon Vent field, Indian Ocean, November 2011

David Shale / Detail of deepsea Sea cucumber (Holothuroidea) from Dragon Vent field, Indian Ocean, November 2011

David Shale / Deepsea Sea cucumber (Holothuroidea) from Dragon Vent field, Indian Ocean, November 2011

David Shale / Detail of deepsea Sea cucumber (Holothuroidea) from Dragon Vent field, Indian Ocean, November 2011

David Shale / Deepsea Sea cucumber (Holothurian) with commensal Polynoid scale worms (Polynoidae) on skin, from coral seamount, Indian Ocean, November 2011

Brandon Cole / Sea Cucumber (Cucumaria miniata), feeding tentacles extended. British Columbia, Canada, Pacific Ocean, September.

Pete Oxford / Donkey Dung sea cucumber (Holothuria mexicana)Coral Reef Island, Belize Barrier Reef, Belize

Jurgen Freund / Sea cucumbers (Holothuroidea) or beche-de-mer gathered from daily gleaning activities undergoing the drying process. Coastal communities are the main supplier of this high value Chinese delicacy. Gree...

Jurgen Freund / Dried sea cucumbers or beche-de-mer gathered from daily gleaning activities. Coastal communities are the main supplier of this high value Chinese delicacy. Green Island, Palawan, Philippines, April 20...

Jurgen Freund / Dried sea cucumbers (Holothuroidea) or beche-de-mer gathered from daily gleaning activities undergoing the drying process. Coastal communities are the main supplier of this high value Chinese delicacy...

Jurgen Freund / Detail of the feet of a Sea cucumber, it crawls across the floor of the sea using hundreds of minute suction cups in the tubular feet, Kimbe Bay, West New Britain, Papua New Guinea.

Jurgen Freund / Graeff's sea cucumber (Bohadschia graeffei) Kimbe Bay, West New Britain, Papua New Guinea

Jurgen Freund / Sea apple (Pseudocolochirus violaceus) with tentacles exposed, feeding, Komodo NP, Indonesia, Indo-pacific.

Jurgen Freund / Sea apple (Pseudocolochirus violaceus) with tentacles exposed, feeding, Komodo NP, Indonesia, Indo-pacific.

Jurgen Freund / Anal hole of Sea cucumber (Thelenota anax) Sipadan, Malaysia.

Jurgen Freund / A carpet of Yellow sea cucumbers (Colochirus robustus) in the reef. North Raja Ampat, West Papua, Indonesia.

Jurgen Freund / Yellow sea cucumber (Colochirus robustus) on a Tunicate (Clavelina robusta). North Raja Ampat, West Papua, Indonesia.

Jurgen Freund / A carpet of Yellow sea cucumbers (Colochirus robustus) in the reef. North Raja Ampat, West Papua, Indonesia, February.

Jurgen Freund / A carpet of yellow sea cucumbers (Colochirus robustus) in the reef. North Raja Ampat, West Papua, Indonesia.

Jurgen Freund / Imperial / Emperor shrimp (Periclimenes imperator / Zenopontonia rex) on a sea cucumber. Lembeh Strait, North Sulawesi, Indonesia.

Jurgen Freund / Prickly Sea Cucumber (Bohadschia graeffei) feeding on seabed, Lembeh Strait, North Sulawesi, Indonesia

Jurgen Freund / A carpet of Yellow sea cucumbers (Colochirus robustus) in the reef. North Raja Ampat, West Papua, Indonesia

Georgette Douwma / Swimming anemone (Boloceroides mcmurrichi) on sea cucumber. Rinca, Komodo National Park, Indonesia, October

Elaine Whiteford / Psolus phantapus sea cucumber (Holothuroidea) on the seabed in Loch Goil, Scotland.

David Shale / Close up of deepsea benthic Sea cucumber (Peniagone sp) with commensal polynoid polychaete, from mid atlantic ridge, depth approx 2600m, June 2010

David Shale / Deepsea benthic Sea cucumber (Peniagone sp) with commensal polynoid polychaete, from mid atlantic ridge, depth approx 2600m, June 2010