Norbert Wu / Orange Tube Coral (Tubastraea aurea) polyps extended only at night, Dutch Antilles, Caribbean

Jeff Rotman / Cup coral {Tubastrea sp} feeding on Silverside fish at night, Red Sea

Alex Mustard / Large green branching coral (Tubastrea sp.) with damselfish on a coral reef. Misool, Raja Ampat, West Papua, Indonesia. Misool Marine Protected Area. Ceram Sea. Tropical West Pacific Ocean.

Doug Perrine / Sea slug (Nembrotha cristata) with crest, crawling amongst Sun coral (Tubastraea sp). Puerto Galera, Mindoro Island, Philippines.

Magnus Lundgren / Wild Wonders of China / Sun / Tube coral (Tubastraea sp) with tentacles extended to catch zooplankton. Gulf of Bohai, Yellow Sea. Penglai / Dengzhou / Tengchow, Yantai, Shandong Province, China.

Magnus Lundgren / Wild Wonders of China / Sun / Tube coral (Tubastraea sp) with tentacles extended to catch zooplankton. Gulf of Bohai, Yellow Sea. Penglai / Dengzhou / Tengchow, Yantai, Shandong Province, China.

Linda Pitkin / Orange cup coral (Tubastraea sp.), and soft corals, Triton Bay, near Kaimana, West Papua, Indonesia

Linda Pitkin / Orange cup corals (Tubastraea sp.), Triton Bay, near Kaimana, West Papua, Indonesia

Alex Mustard / Yellow wentletrap snail (Epitonium sp.) feeding on Cup coral (Tubastraea sp.). Snail laying clutch of eggs. Nusa Kode, Rinca Island, Komodo National Park, Indonesia. South East Asia. Horseshoe Bay, Sa...

Pascal Kobeh / A coral drop off with soft corals (Dendronephthya sp), seafans or gorgonians (Semperina sp) and a hard coral green cup coral (Tubastrea micrantha) Palau, Philippine Sea

Pete Oxford / Black Sun Coral (Tubastraea micranthus) and Sea Goldie (Pseudanthias squamipinnis) school, Fiji

Juergen Freund / Tube coral (Tubastrea sp) Komodo NP, Indonesia.