Juergen Freund / Fluorescent corals (Trachyphyllia geoffroyi) Great Barrier Reef, Australia

Juergen Freund / Fluorescent corals (Favia sp) Great Barrier Reef, Australia

Michael Pitts,Michael Pitts / Coral wall with Anthiinae schooling fish, Red Sea

Franco Banfi / Reef under the surface of shallow waters, at sunset, covered with hard corals, Brush Coral (Acropora hyacinthus) Robust Acropora (Acropora robusta) and other Acropora, Maldives, Indian Ocean

Franco Banfi / Reef under the surface of shallow waters, at sunset, covered with hard corals, Brush Coral (Acropora hyacinthus) Robust Acropora (Acropora robusta) and other Acropora, Maldives, Indian Ocean

David Shale / Solenosmilia sp and eunicid polychaete and bamboo coral. Collected from coral sea mount near Dragon vent field on SW Indian Ridge, Indian Ocean.

Juergen Freund / Coral reef with hard corals and cabbage coral, Komodo NP, Indonesia

Georgette Douwma / Bleached coral {Acropora sp} caused by loss of algae with living purple polyps. Maldives.

Fred Bavendam / Garden of Hard Corals just beneath the water's surface at Bunaken Island, Manado Tua Marine National Park, Manado, North Sulawesi, Indonesia

Fred Bavendam / Garden of Hard Corals just beneath the water's surface at Bunaken Island, Manado Tua Marine National Park, Manado, North Sulawesi, Indonesia

Fred Bavendam / Garden of Hard Corals just beneath the water's surface at Bunaken Island, Manado Tua Marine National Park, Manado, North Sulawesi, Indonesia

Pascal Kobeh / Hard coral (Porites lutea) with Christmas-tree worms (Spirobranchus giganteus), New Caledonia, Pacific Ocean.