Juergen Freund / Timelapse of Giant sea cucumbers (Thelenota ananas) moving underwater, with a Giant clam (Tridacna gigas) in the background, Great Barrier Reef, Queensland, Australia, 2015.

Alex Mustard / 2020VISION / A forest of Sea cucumbers (Psolus phantapus) feeding, extended up out of the sediment in Scottish sea loch, Loch Duich, Ross and Cromarty, Scotland, UK, April

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

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

Juergen Freund / Imperial / Emperor shrimp (Periclimenes imperator / Zenopontonia rex) on an Eyed / Leopard sea cucumber (Bohadschia argus). Lembeh Strait, North Sulawesi, Indonesia

Juergen Freund / Imperial / Emperor shrimp (Periclimenes imperator / Zenopontonia rex) on an Eyed / Leopard sea cucumber (Bohadschia argus). Lembeh Strait, North Sulawesi, Indonesia.

Juergen Freund / Imperial / Emperor shrimps (Periclimenes imperator / Zenopontonia rex) on a sea cucumber. 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

David Shale / Underside of deepsea Sea cucumber (Deima validum) from 2500m, mid Atlantic ridge, June 2010

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...

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