Juergen Freund / Gorgonian fan coral with Featherstar / crinoid attached, West New Britain, Papua New Guinea.

Georgette Douwma / Coral reef scenery with Gorgonian and shoal of Pygmy / Glassy sweepers (Parapriacanthus guentheri) Egypt, Red Sea

Fred Bavendam / Crescent-tail Bigeye (Priacanthus hamrur) in front of a sea fan, Uepi Island, Solomon Islands

Georgette Douwma / Longnose hawkfish (Oxycirrhites typus) resting in Gorgonian coral. Red Sea, Egypt.

Georgette Douwma / Longose hawkfish (Oxycirrhites typus) resting on Gorgonian coral. Red Sea, Egypt.

Chris Newbert / Underwater reef scene with Sea Whips, Gorgonian Whip Coral, blossoming Soft Corals, Guard Plate Coral, and schools of Pseudanthias, Red Sea, Egypt

Chris Newbert / Soft Coral (Dendronephthya sp) outcroppings, Sea Fan (Subergorgia sp) and Glassfish (Parapriacanthus ransonneti)

Georgette Douwma / Gorgonian / Sea whip coral (Ellisella ceratophyta), close up, West Papua, Indonesia.

Linda Pitkin / Sea whips, gorgonian coral (Ellisella sp.) Cape Kri, Dampier Strait, Raja Ampat, West Papua, Indonesia, March 2016

Alex Mustard / Red gorgonians (Lophogorgia chilensis) growing beneath a Giant kelp (Macrocystis pyrifera) forest, with female California sheephead (Semicossyphus pulcher). Santa Barbara Island, Channel Islands. Los...

Alex Mustard / Red gorgonian (Lophogorgia chilensis) growing beneath a forest of giant kelp (Macrocystis pyrifera), with female California sheephead fish (Semicossyphus pulcher). Santa Barbara Island, Channel Island...

Alex Mustard / Red gorgonian (Lophogorgia chilensis) growing beneath a forest of Giant kelp (Macrocystis pyrifera). Santa Barbara Island, Channel Islands. California, USA. North East Pacific Ocean.

Georgette Douwma / Gorgonian coral (Acanthogorgia sp.) Similan Islands, Andaman Sea, Thailand.

Franco Banfi / Red gorgonian coral (Lophogorgia chilensis) and Yellow gorgonian (Eunicella cavolini) growing in a rock crevice, Ponza Island, Italy, Tyrrhenian Sea, Mediterranean.

Franco Banfi / Scuba diver with Red gorgonian coral (Paramuricea clavata), Santa Teresa, Sardinia, Italy, Tyrrhenian Sea, Mediterranean.

Franco Banfi / Mediterranean feather star (Antedon mediterranea) on a White gorgonian coral (Eunicella singularis), Punta Campanella Marine Reserve, Massa Lubrense, Italy, Tyrrhenian Sea, Mediterranean.

Franco Banfi / Red gorgonian coral (Paramuricea clavata) covered with mucilage, a symptom of rising sea temperature, Ventimiglia, Italy, Ligurian Sea, Mediterranean.

Franco Banfi / Red gorgonian coral (Paramuricea clavata) covered with mucilage, a symptom of rising sea temperature, Punta Campanella Marine Reserve, Massa Lubrense, Italy, Tyrrhenian Sea, Mediterranean.

Franco Banfi / Yellow gorgonian (Eunicella cavolini), Vis Island, Croatia, Adriatic Sea, Mediterranean

Franco Banfi / Red fan corals (Paramuricea clavata), Yellow gorgonian, (Eunicella cavolini) and Yellow cave-sponges (Aplysina cavernicola), Ischia Island, Italy, Tyrrhenian Sea, Mediterranean.

Franco Banfi / Scuba diver with Red gorgonian coral (Lophogorgia chilensis), Ponza Island, Italy, Tyrrhenian Sea, Mediterranean.

Franco Banfi / Scuba diver with Red gorgonian coral (Lophogorgia chilensis), Punta Campanella Marine Reserve, Massa Lubrense, Italy, Tyrrhenian Sea, Mediterranean.

Franco Banfi / Wide angle of a group of Sea stars (Hacelia attenuata), Vis Island, Croatia, Adriatic Sea, Mediterranean.

Franco Banfi / Yellow gorgonian (Eunicella cavolini) covered with mucilage, a symptom of rising sea temperature, Vis Island, Croatia, Adriatic Sea, Mediterranean.

Franco Banfi / Mucilage covering a reef, Vis Island, Croatia, Adriatic Sea, Mediterranean.

Franco Banfi / Red gorgonian coral (Paramuricea clavata) covered in mucilage, a symptom of rising sea temperature, Punta Campanella Marine Reserve, Massa Lubrense, Italy, Tyrrhenian Sea, Mediterranean.

Franco Banfi / Two Red sea-squirts (Halocynthia papillosa) on a Yellow gorgonian (Eunicella cavolini), Punta Campanella Marine Reserve, Massa Lubrense, Italy, Tyrrhenian Sea, Mediterranean.

Georgette Douwma / Shimmering cardinals (Archamia lineolata) on coral reef with Red rope sponge (Amphimedon compressa) and soft corals and a gorgonian in background. Egypt, Red Sea.

Georgette Douwma / Shimmering cardinals (Archamia lineolata) on coral reef with Red rope sponge (Amphimedon compressa) and soft corals and a gorgonian in background. Egypt, Red Sea.

Franco Banfi / Red seafan (Paramuricea clavata) Yellow gorgonian (Eunicella cavolini), Yellow sponges (Aplysina cavernicola) and Yellow cluster anemone (Parazoanthus axinellae) Punta Sant'Angelo dive-site, Ischia Is...

Franco Banfi / Scuba diver and Red seafan (Paramuricea clavata) Yellow gorgonian (Eunicella cavolini) and Yellow Cluster Anemone (Parazoanthus axinellae), Punta Sant'Angelo dive-site, Ischia Island, Italy, Tyrrhenia...

Franco Banfi / Red seafan (Paramuricea clavata) Yellow gorgonian (Eunicella cavolini) and Yellow Cluster Anemone (Parazoanthus axinellae) Punta Sant'Angelo dive-site, Ischia Island, Italy, Tyrrhenian Sea, Mediterran...

Franco Banfi / Gorgonian sea fan (Acalycigorgia sp.) Raja Ampat, Irian Jaya, West Papua, Indonesia, Pacific Ocean

Juergen Freund / Brittlestar (Ophiothrix purpurea) on gorgonian fan coral, Papua New Guinea.

Juergen Freund / Detail of a Gorgonian fan coral, Papua New Guinea.

Birgitte Wilms / Sea Fan (Acabaria sp) with polyps extended for feeding, Solomon Islands

Birgitte Wilms / Soft coral and sea fan, Solomon Islands

Birgitte Wilms / Soft coral and sea fan, Solomon Islands

Juergen Freund / Large fan coral (Muricella sp) Misool, Raja Ampat, West Papua, Indonesia, January

David Shale / Brittlestar (Ophiuroidea) on Gorgonian seafan coral mid Atlantic Ridge, June 2010

GEORGETTE DOUWMA / Coral reef scenery with Gorgonian and shoal of Pygmy / Glassy sweepers (Parapriacanthus guentheri) Egypt, Red Sea.

Jeff Rotman / Winged oyster (Pteria aegyptiaca) growing on Gorgonia coral, Red Sea

Wild Wonders of Europe / Pitkin / Gorgonian coral (Paramuricea clavata) 'Horsehead', Lavezzi Islands, Corsica, France, September 2008

Hiroya Minakuchi / Longnose Hawkfish (Oxycirrhites typus) camouflaged on sea fan, Celebes Sea

Fred Bavendam / White-lined Rock Cod (Anyperodon leucogrammicus) in front of sea fan, Kimbe Bay, Papua New Guinea

Chris Newbert / Soft Coral (Dendronephthya sp) and Sea Fan (Melithaea sp) on mangrove root, Indonesia

GEORGETTE DOUWMA / White-belly damselfish (Amblyglyphidodon leucogaster) pair spawning on Gorgonian coral / Sea fan. Egypt, Red Sea

GEORGETTE DOUWMA / Klein's butterflyfish (Chaetodon kleinii) amongst gorgonian coral / sea fan. Raja Ampat, West Papua, Indonesia

GEORGETTE DOUWMA / Brittlestars (Ophiothrix sp) wrapped round arms of Gorgonian coral / Sea fan. Raja Ampat, West Papua, Indonesia

GEORGETTE DOUWMA / Brittlestars (Ophiothrix sp) wrapped round arms of Gorgonian coral / Sea fan. Raja Ampat, West Papua, Indonesia

GEORGETTE DOUWMA / Longose hawkfish (Oxycirrhites typus) resting on Gorgonian coral. Red Sea, Egypt.

GEORGETTE DOUWMA / Longose hawkfish (Oxycirrhites typus) resting on Gorgonian coral. Red Sea, Egypt.

Birgitte Wilms / Trumpetfish (Aulostomus sp) on Sea Fan (Melithaea sp), 60 feet deep, Solomon Islands

GEORGETTE DOUWMA / Gorgonian fan coral / Sea fan {Gorganacea} Bunaken, Sulawesi, Indonesia

GEORGETTE DOUWMA / Gorgonian fan coral {Gorganacea} with polyps feeding, Great barrier reef, Queensland, Australia

Chris Newbert / Longnose Hawkfish (Oxycirrhites typus) on Sea Fan (Siphonogorgia sp) 60 feet deep, Papua New Guinea

Chris Newbert / Sea Fan (Melithaea sp) small Sea Fan (Subergorgia sp) and Fusiliers on a coral reef, 50 feet deep, Papua New Guinea

Chris Newbert / Sea Fan (Subergorgia sp) Soft Coral (Dendronephthya sp) and Anthias (Pseudanthias sp) 50 feet deep, Red Sea, Egypt

Birgitte Wilms / Sea Fan (Subergorgia sp) surrounded by schooling reef fish, Red Sea, Egypt

Norbert Wu / Seahorse (Hippocampus sp) on Sea Fan, related to Pipefish, Papua New Guinea

Chris Newbert / Common Lionfish (Pterois volitans) group surrounded by Sea Fans (Melithaea sp) 60 feet deep, Solomon Islands

Fred Bavendam / Sea Fan (Gorgoniidae) and red and yellow Soft Coral (Dendronephthya sp) covering rock, Ko Tachi, Andaman Sea, Thailand

Jeff Rotman / Hurghada Star {Fromia ghardaqana} feeding on Gorgonian coral, Red Sea.

Jeff Rotman / Red gorgonian coral polyps open {Lophogorgia chilensis} Channel Is, California, USA

Gary Bell/ Oceanwide / Gorgonian (Acalycigorgia sp) polyps, Great Barrier Reef, Australia

David Fleetham / Necklace seastar (Fromia monilis) on gorgonian coral, Indonesia.

David Fleetham / Crinoid / feather star (Liparometra regalis) on red Gorgonian coral, on wreck of the Fujikawa Maru, Truk Lagoon, Micronesia. The white "fuzzy" look to the coral is the coral polyps feeding.

Pete Oxford / Sea fans, Raja Ampat Islands, Indonesia

Roberto Rinaldi / Diver and red whip coral or gorgonian whip coral (juncella sp), Palau.

Roberto Rinaldi / Detail of a Gorgonian sea fan (Gorganacea sp.) structure, Great Barrier Reef, Australia

Roberto Rinaldi / Squat lobster (Galathea squamifera) on red gorgonian seafan (Paramuricea clavata), Elba, Italy.

David Hall / RF - Gorgonian coral sea fans (Melithaea sp.) with Yellowtail fusiliers (Caesio cuning) and Banana fusiliers (Pterocaesio pisang) feeding on zooplankton in midwater. Also seen among the sea fans are D...

David Hall / Moorish idol (Zanclus cornutus) swimming past a reef covered with Coral sea fans including (Melithaea sp.) and (Pseudopterogorgia sp.), Soft corals (Dendronephthya sp), (Chironephthya sp.) and (Sclero...

Alex Mustard / Pygmy seahorse (Hippocampus bargibanti) among a Sea fan (Muricella sp.) on a coral reef, Bitung, North Sulawesi, Indonesia. Lembeh Strait, Molucca Sea.

Alex Mustard / RF - Golden damselfish (Amblyglyphidodon aureus) and Threadfin anthias (Pseudanthias huchti) swimming around a large gorgonian (Subergorgia sp.) on a coral reef wall, Tubbataha Atolls, Palawan, Philip...

Sergio Hanquet / Gorgonian fan coral (Subergorgia mollis) on coral reef, Ari Atoll, Maldives, Indian Ocean.

David Fleetham / Diver swimming past coral reef with Gorgonian fans (Alcyonacea sp.), Red whip corals (Leptogorgia virgulata), Bluespot butterflyfish (Chaetodon plebeius), Fiji, Pacific Ocean.

Joel Sartore / Photo Ark / Red finger gorgonian (Diodogorgia nodulifera) portrait, Butterfly Pavilion, Colorado. Captive.

Franco Banfi / Forkbeard / Musdea (Phycis phycis) swimming through Red gorgonian (Paramuricea clavata), Marine Protected area Punta Campanella, Costa Amalfitana, Italy, Tyrrhenian Sea.

Franco Banfi / Gold coral (Savalia Savaglia) colonising Red gorgonian (Paramuricea clavata), Marine Protected area Punta Campanella, Costa Amalfitana, Italy, Tyrrhenian Sea.

Franco Banfi / Spiny starfish (Marthasterias glacialis), Sponge (Sarcotragus foetidus) and Red gorgonian (Paramuricea clavata) colonising the crossbars of a sunken electricity pylon that fell into the sea during a s...

Franco Banfi / Red and yellow gorgonian (Paramuricea clavata) and Sponge (Sarcotragus foetidus) colonising the crossbars of a sunken electricity pylon that fell into the sea during a storm, Capri Island, Costa Amalf...

Franco Banfi / Shoal of Mediterranean Fairy basslet (Anthias anthias) swimming between Red gorgonian (Paramuricea clavata) that have colonised the crossbars of a sunken electricity pylon that fell into the sea durin...

Franco Banfi / Shoal of Mediterranean Fairy basslet (Anthias anthias) swimming between Red gorgonian (Paramuricea clavata) that have colonised the crossbars of a sunken electricity pylon that fell into the sea durin...

Franco Banfi / Shoal of Mediterranean Fairy basslet (Anthias anthias) swimming between Red gorgonian (Paramuricea clavata) that have colonised the crossbars of a sunken electricity pylon that fell into the sea durin...

Noemie Stroh / Gorgonian fans (Annella mollis) on a healthy reef, Gordon Reef, Strait of Tiran, Red Sea, Egypt, September.

Alex Mustard / Tiny (1cm) Pygmy seahorse (Hippocampus bargibanti) hides in the branches of its home seafan (Muricella sp.) on a coral reef. Daram Islands, Misool, Raja Ampat, West Papua, Indonesia. Ceram Sea.

Franco Banfi / Catshark egg, (Scyliorhinus sp.), on Red Gorgonian, (Paramuricea clavata), Punta Campanella Marine Protected area, Costa Amalfitana / Amalfi coast, Italy, Tyrrhenian Sea, Mediterranean. October

Franco Banfi / Scuba diver with Red gorgonian (Paramuricea clavata) Punta Campanella Marine Protected Area, Costa Amalfitana, Italy, Tyrrhenian Sea, Mediterranean.

Franco Banfi / Scuba diver with red gorgonian (Paramuricea clavata) Punta Campanella Marine Protected Area, Costa Amalfitana, Italy, Tyrrhenian Sea, Mediterranean.

Franco Banfi / Catshark egg cases (Scyliorhinus sp.) on Red gorgonian (Paramuricea clavata) Banco di Santa Croce, Penisola Sorrentina, Costa Amalfitana, Italy, Tyrrhenian Sea, Mediterranean.

Franco Banfi / Seafan / Red gorgonian (Paramuricea clavata) and Light-bulb sea squirt (Clavelina lepadiformis) Punta Carena, Capri Island, Sorrentine Peninsula, Italy, Tyrrhenian Sea, Mediterranean.

Franco Banfi / Red sea fan (Paramuricea clavata) with gorgonian corals and Light-bulb sea squirt (Clavelina lepadiformis) Punta Carena, Capri Island, Sorrentine Peninsula, Italy, Tyrrhenian Sea, Mediterranean.

Franco Banfi / Red sea fan (Paramuricea clavata) with gorgonian corals and Light-bulb sea squirt (Clavelina lepadiformis) Punta Carena, Capri Island, Sorrentine Peninsula, Italy, Tyrrhenian Sea, Mediterranean.