Georgette Douwma / Kaleidoscopic image of Sea apple (Pseudocolochirus violaceus). Komodo National Park, Indonesia.

Georgette Douwma / Yellow sea cucumbers (Colochirus robustus) feeding in current. Triton Bay, West Papua, Indonesia.

Linda Pitkin / Leather coral (Sarcophyton sp.), on a rock with soft corals and Yellow Sea Cucumbers (Colochirus robustus), Triton Bay, near Kaimana, West Papua, Indonesia

Linda Pitkin / Sea cucumber (Pseudocolochirus violaceus) Rinca, Komodo National Park, Indonesia.

Linda Pitkin / Sea Cucumber (Colochirus robustus) Rinca, Komodo National Park, Indonesia

Linda Pitkin / Sea cucumber / Sea apple (Pseudocolochirus violaceus) Rinca, Komodo National Park, Indonesia.

Georgette Douwma / Sea apple (Pseudocolochirus violaceus) Komodo National Park, Indonesia.

Georgette Douwma / Sea apple (Pseudocolochirus violaceus) Komodo National Park, Indonesia.

Georgette Douwma / Sea apple (Pseudocolochirus violaceus) on coral reef. It feeds by filtering the water column with its tentacular crown, successively bringing each arm into its mouth to deliver food particles. Komod...

Juergen Freund / Sea apple (Pseudocolochirus violaceus) feeding, Komodo National Park, Indonesia.

Solvin Zankl / Yellow sea cucumber (Colochirus robustus) on coral reef, Raja Ampat, West Papua, Indonesia, Pacific Ocean.

Franco Banfi / Sea cucumber (Colochirus robustus) Friwinbonda Point, Kri island, Raja Ampat, Irian Jaya, West Papua, Indonesia, Pacific Ocean

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

Birgitte Wilms / Yellow Sea Cucumber (Colochirus robustus) colony, Indonesia

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

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

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

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

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

GEORGETTE DOUWMA / Yellow sea cucumber (Colochirus robustus) on sponge. Komdo National Park, Indonesia

GEORGETTE DOUWMA / Yellow sea cucumbers (Colochirus robustus) on sponge, feed by catching substances in the water with its finely branched tentacles. Komdo National Park, Indonesia

Georgette Douwma / Sea cucumber (Colochirus robustus) Rinca, Indonesia

Constantinos Petrinos / Yellow Sea cucumber {Colochirus rubustus} Sulawesi, Indonesia

Georgette Douwma / Composite image of marine invertebrates on black background. Top row from left: Tube anemone (Ceriantharia), Yellow sea cucumber (Colochirus robustus), Nudibranch (Nembrotha lineolata), Squat shri...

Georgette Douwma / Composite image of echinoderms on black background. top left to right: Pineapple sea cucumber (Thelenota ananas), Yellow sea cucumber (Colochirus robustus), Frianti's starfish (Nardoa frianti),...

Georgette Douwma / Composite image of echinoderms on black background. Top row from left: Featherstar (Crinoidea), Sea apple (Pseudocolochirus violaceus). Central row from left: Mosaic cushion star (Halityle regu...

Georgette Douwma / Composite image of echinoderms on black background. SEA CUCUMBER row from left: Pineapple sea cucumber (Thelenota ananas), Leopard sea cucumber (Bohadschia argus), Yellow sea cucumber (Colochirus...

Georgette Douwma / Composite image of echinoderms on black background. Species present: - Top row from left: Yellow sea cucumber (Colochirus robustus) and Lampert's sea cucumber (Synaptula lamperti), Black sea c...

David Fleetham / Sea Apple sea cucumber (Pseudocholochirus violaceus), feeding on on passing plankton. Komodo National Park, Indonesia.