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

Alex Mustard / Hard coral reef (Porites sp.) exposed by a low spring tide in front of an island. Yillet Island, Misool, Raja Ampat, West Papua, Indonesia. Ceram Sea. Tropical West Pacific Ocean.

Alex Mustard / Hard coral (Porites sp.) micro-atoll. A microatoll is a circular colony of coral, dead on the top from exposure to air at low tide, but living around the edge. Their presence in coral reef fossils is...

SCOTLAND: The Big Picture / Colourful rocky reef with Dead man's finger (Alcyonium digitatum) and Kelp forest, North Sea, Shetland

SCOTLAND: The Big Picture / Soft coral / Dead man's finger (Alcyonium digitatum) growing on a rocky reef with kelp forest above, Scotland, UK, February.

Linda Pitkin / Stony coral (Porites sp.) with Anthias (Pseudanthias squamipinnis) Ras Ghozlani, Ras Mohammed National Park, Egypt, Red Sea.

Linda Pitkin / Stony coral (Porites sp.) with Anthias (Pseudanthias squamipinnis), and diver Ras Ghozlani, Ras Mohammed National Park, Egypt, Red Sea.

Linda Pitkin / Green finger sponge (Iotrochota birotulata), with colonies of Golden zoanthids (Parazoanthus swiftii), on Netted barrel sponge (Verongula gigantea), on coral reef Klein Bonaire, Bonaire, Leeward Antil...

Alex Mustard / Reef octopus (Octopus cyanea) emerges from its den in a hole in a large hard coral (Porites sp.) at sunset. Sha'ab Mahmood, Sinai, Egypt. Red Sea

Alex Mustard / Hard corals (Porites sp. ) grow in shallow water around limestone rock islands. Korror, Palau, Mirconesia. Tropical west Pacific Ocean

Sue Daly / Deadman's finger soft coral (Alcyonium digitatum) Trondheimsfjord, Norway, July.

Constantinos Petrinos / Giant flathead (Cymbacephalus beauforti) lying on a Finger Leather Coral (Sinularia polydactyla) Lembeh Strait, North Sulawesi, Indonesia.

Constantinos Petrinos / Giant flathead (Cymbacephalus beauforti) lying on a Finger Leather Coral (Sinularia polydactyla) Lembeh Strait, North Sulawesi, Indonesia.

Constantinos Petrinos / Giant flathead (Cymbacephalus beauforti) lying on a Finger Leather Coral (Sinularia polydactyla) Lembeh Strait, North Sulawesi, Indonesia.

SCOTLAND: The Big Picture / Elegant anemone (Sagartia elegans) and Dead man's finger (Alcyonium digitatum) with fish swimming in plankton bloom in background, South Arran Marine Protected Area, Isle of Arran, Scotland, UK, Augus...

Doug Perrine / Plate and Pillar coral (Porites rus) and Cauliflower coral (Pocillopora meandrina) bleached by warm sea temperatures during 2015 El Nino event, Honaunau Bay, Kona, Hawaii, USA.

Alex Mustard / Dome coral (Porites nodifera) pinnacle or bommie surrounded by fish, including Scalefin anthias (Pseudanthias squamipinnis), with diver Fury Shoal, Egypt. Red Sea.

Alex Mustard / Chocolate-dip chromis (Chromis dimidiata) male over out of focus hard coral (Porites nodifera). Sha'ab Claudia, Fury Shoal, Egypt. Red Sea

Pete Oxford / Squirrelfish (Holocentrus adscensionis) Halfmoon Caye, Lighthouse Reef Atoll. Belize.

Alex Mustard / Colony of Finger coral (Porites porites) on a shallow coral reef. Cayman Brac, Cayman Islands. Caribbean Sea.

Georgette Douwma / Porites coral, stony coral boulders. Egypt, Red Sea.

Pascal Kobeh / Diver near barrel sponge (Xestospongia testudinaria), hard coral (Porites sp) and red whip coral (Ctenocella sp), Walindi, Papua New Guinea, Bismarck Sea.

Pascal Kobeh / Debris of dead corals (Acropora and Porites ) probably due to the bleaching of 1998 an El Nino year which killed a large amount of Maldive corals, Maldives. Indian Ocean.

Pascal Kobeh / Diver on top of a flatreef with hard corals and Acropora tables (Acropora and Porites ) and reef fish, Maldives. Indian Ocean. March 2013.

Pascal Kobeh / Diver on a reef with hard corals (Porites) and Table corals (Acropora) and Magnificent sea anemone (Heteractis magnifica) with Maldives anemonefish (Amphiprion nigripes) Maldives. Indian Ocean. March...

Pascal Kobeh / Coral drop off with soft corals (Dendronephthya) and (Sarcophyton ), hard corals (Acropora) and (Porites) and Jewel fairy basslets (Pseudanthias squamipinnis) Sudan. Red Sea.

Pascal Kobeh / Coral drop off with hard corals possibly (Porites) and Kewel fairy basslets (Pseudanthias squamipinnis) Sudan. Red Sea.

Pascal Kobeh / Coral drop off with hard corals (Porites) and jewel fairy basslets (Pseudanthias squamipinnis) and two-band anemonefish (Amphiprion bicinctus) in a Mertens' sea anemone (Stichodactyla mertensii) Sudan...

Pascal Kobeh / Yellowmouth / Starry moray (Gymnothorax nudivomer) coming out of its hole in a hard coral reef (Porites), coast of Dhofar and Hallaniyat islands, Oman. Arabian Sea.

Pascal Kobeh / Oman anemonefish / clownfish (Amphiprion omanensis) in a Leathery sea anemone (Heteractis crispa) near a hard coral (Porites) with Variable-lined fusiliers (Caesio varilineata) and a diver in the back...

Pascal Kobeh / Common bigeyes (Priacanthus hamrur) on a hard coral reef with (Acropora) and (Porites) Palau. Philippine Sea.

Alex Mustard / Hard, reef building corals (Acropora spp) and (Porites sp.) growing on shallow coral bommie. The Alternatives, Ras Mohammed, Sinai, Egypt. Red Sea.

Solvin Zankl / Christmas tree worms (Spirobranchus giganteus) on Porites coral (Porites sp) Raja Ampat, West Papua, Indonesia, Pacific Ocean.

Alex Mustard / Mixed hard coral including finger coral (Porites porites) and soft corals growing on reef, Little Cayman, Cayman Islands, British West Indies, Caribbean Sea.

Alex Mustard / Star coral (Montastraea annularis) black searod (Plexaura homomalla) and finger coral (Porites porites) with a snorkeller exploring a shallow coral reef, East End, Grand Cayman, Cayman Islands, Britis...

Jeff Rotman / Stony Finger Coral (Acropora humilis). Papua New Guinea, Bismarck Sea.

Pete Oxford / Clubbed Finger Coral (Porites porites), Bonaire, Netherlands Antilles, Caribbean

Juergen Freund / Hard / stone coral (Porites sp) Moluccas Islands, Indonesia.

Juergen Freund / Coral reef with a big boulder coral (Porites sp.) and diver. Misool, Raja Ampat, West Papua, Indonesia, January 2010.

Juergen Freund / Finger coral (Porites sp) growing from a coral pillar, Sipadan, Malaysia.

Martha Holmes / Club finger coral {Porites porites} with extended polyps, Jamaica, Caribbean

GEORGETTE DOUWMA / Finger coral {Porites cylindrica} and Bristlestar, Great Barrier Reef, Australia

GEORGETTE DOUWMA / Porites / Finger coral (Porites genus) with bite marks of a Bumphead parrotfish (Bolbometopon muricatum) Misool, Raja Ampat, West Papua, Indonesia.

GEORGETTE DOUWMA / Porites / Finger coral (Porites genus) with bite marks of a Bumphead parrotfish (Bolbometopon muricatum). Misool, Raja Ampat, West Papua, Indonesia.

Tim Laman / Massive hard coral (Porites sp.) with bite marks from feeding Parrot fish (Scarus sp) on a coral reef in Palau, Micronesia.

Norbert Wu / Common Squirrelfish (Holocentrus adscensionis) Pennant Bannerfish (Heniochus chrysostomus) and Emperor Angelfish (Pomacanthus imperator) near soft coral ledge, Raja Ampat Islands, Indonesia

Martha Holmes / Club finger coral (Porites porites) with polyps extended, Jamaica, Caribbean

Juergen Freund / Stone coral {Porites sp} with parrotfish bite scratches, Indo-Pacific

Doug Perrine / Longsnout seahorse {Hippocampus reidi} in Finger coral {Porites sp} Caribbean

Fred Bavendam / Clubbed Finger Coral (Porites porites), South Caicos, British West Indies

Jeff Rotman / Finger-like towers of Staghorn coral (Tubinaria mesenterina), Red Sea, Egypt

Jeff Rotman / Reef fish asleep amongst fingers of Staghorn Coral (Acropora sp) Red Sea, Egypt

Francis Abbott / Finger coral {Porites lutea} Bahrain, Persian Gulf

Francis Abbott / Finger coral {Porites nodifera} Persian Gulf

Jeff Rotman / Finger coral {Porites sp} Papua New Guinea

Roberto Rinaldi / Diver looking at Orange finger sponge (Neoesperiopsis rigida), Tasmania, Australia

Roberto Rinaldi / Orange finger sponge (Neoesperiopsis rigida) and silhouette of diver, Tasmania, Australia.

Roberto Rinaldi / Reef crab / seven-eleven / dark finger coral crab (Carpilius macultatus), Sipadan, Borneo, Malaysia.

Roberto Rinaldi / A scuba diver exploring underwater with Whip corals (Gorgonacea sp) and Orange finger sponges (Neoesperiopsis rigida), Tasmania, Australia

Roberto Rinaldi / Blue coral (heliopora sp) surrounded by finger leather coral (Sinularia sp), Lankayan island, Borneo, Malaysia.

Doug Perrine / Flame angelfish (Centropyge loriculus) swimming on coral reef, with Finger coral (Porites compressa) behind, Ho'okena, South Kona, Hawaii, Pacific Ocean.

Doug Perrine / White-tail chromis (Chromis leucura) swimming amongst branches of Finger coral (Porites compressa), Ho'okena, South Kona, The Big Island, Hawaii, USA, Pacific Ocean.

Alex Mustard / Boulder coral (Porites sp.) bleached on a coral reef as a result of elevated water temperatures, which cause the coral to expel its zooxanthellae. This bleaching occured in late 2022, due to warming w...

Tui De Roy / Razor surgeonfish (Prionurus laticlavius) and schooling Blacktip cardinalfish (Apogon atradorsatus) swimming over coral reef with Lobe coral (Porites lobata). Galapagos Islands, Ecuador. Pacific Oce...

Doug Perrine / Day octopus (Octopus cyanea) resting on Fringe coral (Porites compressa) in coral reef, Honokohau, North Kona, Big Island, Hawaiian Islands, Pacific Ocean.

Doug Perrine / Day octopus (Octopus cyanea) sitting on Lobe coral (Porites lobata) and placing tentacles beneath it to flush out fish, shadowed by Manybar goatfish (Parupeneus multifasciatus), their hunting partner...

Joel Sartore / Photo Ark / Corky sea finger (Briareum asbestinum) portrait, Indianapolis Zoo, Indiana. Captive.

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

David Fleetham / Rice coral (Montipora flabellata) attempting to outgrow finger coral (Porites compressa) on coral reef, Hawaii, Pacific Ocean.

Doug Perrine / Teardrop butterflyfish (Chaetodon unimaculatus) feeding on Lobe coral (Porites lobata) on reef, North Kona, Hawaii, Pacific Ocean.

Doug Perrine / Big longnose butterflyfish (Forcipiger longirostris) displaying rare, half-dark color phase, swimming over Finger coral ( Porites compressa), North Kona, Hawaii, Pacific Ocean.

Alex Mustard / Papuan scorpionfish (Scorpaenopsis papuensis) resting on hard coral (Porites sp.) on the reef, Similan Islands, Thailand, Andaman Sea.

Joel Sartore / Photo Ark / Cabbage leather coral (Sinularia brassica) on white background, Fort Wayne Children's Zoo. Captive.

Joel Sartore / Photo Ark / Corky sea finger (Briareum asbestinum) on white background, Indianapolis Zoo.

Doug Perrine / Whitesaddle goatfish (Parupeneus porphyreus) resting on head of Lobe coral (Porites lobata), South Kohala, Hawaii, Pacific Ocean.

Alex Mustard / Female Slingjaw wrasse (Epibulus insidiator) swimming over hard corals (Pavona sp.), (Porites sp.) and (Pocillopora sp.) in shallow water, Jackson Reef, Sinai, Egypt, Red Sea.

Alex Mustard / Hard coral (Pocillopora sp.), (Acropora sp.) and (Porites sp.) garden in shallow water, Jackson Reef, Sinai, Egypt, Red Sea.

Alex Mustard / Abundant growth of hard coral including (Porites sp.) and (Acropora sp.) with schools of Blue-green chromis (Chromis viridis) in the background, Laamu Atoll, Maldives, Indian Ocean.

Claudio Contreras / Diver inspecting Staghorn coral (Acropora cervicornis) and Finger coral (Porites porites) colonies. Roatan Island, Honduras. Caribbean Sea.

SCOTLAND: The Big Picture / Dead-man's finger (Alcyonium digitatum), close up of feeding polyps, Levenwick, Shetland, Scotland, North Atlantic Ocean, UK.

SCOTLAND: The Big Picture / Common hermit crab (Pagurus bernhardus) nestled in the polyps of Dead-man's finger (Alcyonium digitatum), Lwerick, Shetland, Scotland, North Atlantic Ocean, UK..

Franco Banfi / Yellow sun seastar (Solaster endeca) and Dead man's finger (Alcyonium digitatum) on rock, Trondheimfjord, Norway, North Atlantic Ocean.

Shane Gross / Finger sponge (Isodictya quatsinoensis) and juvenile Widow rockfish (Sebastes entomelas) along with various anemone and coral species on a wall, Browning Passage, Queen Charlotte Strait, Vancouver Isl...

David Fleetham / Mandarinfish (Synchiropus splendidus) leaving the protection of finger coral to look for a mate at dusk, Yap, Micronesia, Pacific Ocean.

Pascal Kobeh / A coral reef with soft corals (Dendronephthya sp. and Scleronephthya sp.), hard corals (Acropora sp. and Porites sp.), fire corals (Millepora tenella) and Jewel fairy basslets (Pseudanthias squamipinn...

Alex Mustard / Orange and white soft corals, Dead men's finger (Alcyonium digitatum) are surrounded by pink/purple feather stars (Antedon pelasus). Lochcarron, Ross-shire, Ross and Cromarty, Highlands, Scotland,...

David Fleetham / Bridled anemonefish (Amphiprion frenatus) in a Bulb-tenacle sea anemone (Entacmaea quadricolor) in reef of finger coral, Yap, Micronesia.

Alex Mustard / Dense and diverse growth of hard corals (including Porites sp. and Acropora spp.). Sha'ab Claudia, Fury Shoal, Egypt. Red Sea

Alex Mustard / Split level photo of mangrove scenery, with hard corals ( including Goniopora sp.; Heliopora sp; Porites sp.) growing below Red mangrove tree: (Rhizophora mangle). Nampale Islands, Misool, Raja Ampat,...

Alex Mustard / Coral pinnacle covered in rich hard coral growth Finger coral (Porites sp) and Star coral (Orbicella faveolata). Bodden Town, Grand Cayman, Cayman Islands, British West Indies. Caribbean Sea.

Doug Perrine / Algae growing over dead Finger coral (Porites compressa), coral bleaching caused by high ocean temperatures during El Nino event. Honaunau Bay, Kona, Hawaii, USA. September 2015.

Doug Perrine / Lobe coral (Porites lobata) bleached during marine heatwave, coral head on left is dead and eroding. Honaunau Bay, South Kona, Hawaii, USA. 2019.

Doug Perrine / Coral reef with Hard coral (Porites sp), bleached due to high water temperatures during El Nino event. Fish swimming above reef. Kamakahonu, Kailua Bay, Kona, Hawaii, USA. December 2015.

Doug Perrine / Bleached coral reef with dead Cauliflower coral (Pocillopora grandis) in middle of large Plate and pillar coral (Porites rus). Bleached by high ocean temperatures during El Nino event. Honaunau Bay, K...

David Hall / Schooling yellowtail rockfish (Sebastes flavidus) with white plumose anemones, red soft coral, brown finger sponges, and an orange bloodstar. This fish often schools with other rockfish species. Hunt...