Lophelia pertusa: Cold-water Coral Mounds from the northwest coast of Morocco.

Cold-water Coral Mounds are found around the margins of the Atlantic Ocean, and adjacent seas such as the Mediterranean and Gulf of Mexico, from Norway and North Carolina in the north to Angola and Argentina in the south, at depths of between 200 and 1000 m. These Coral Mounds are grouped into provinces, numbering from a few tens to many hundreds of individual Mounds, spread along isobaths (control lines) in generally linear arrangements, sometimes merging to form continuous reefs that stretch for hundreds of kilometres. The shape of individual Mounds varies considerably, from elongate or v-shaped to circular or oval, apparently in response to local current conditions, with Mounds ranging from a few metres in height to over 300 m, and extending laterally for tens to hundreds of metres. These Mounds are constructed principally by the Cold-water Coral Lophelia pertusa, with other Corals and Shellfish making a contribution, as well as trapped sediments, both carbonate and siliclastic, and form slowly over hundreds of thousands of years, and are thought to represent a significant sink for atmospheric carbon.

In a paper published in the journal Marine Geology in February 2019, Dierk Hebbeln, Maren Bender and Stefanie Gaide of the Center for Marine Environmental Sciences at the University of Bremen, Jürgen Titschack, also of the Center for Marine Environmental Sciences at the University of Bremen, and of the Marine Research Department at Senckenberg am Meer, Thomas Vandorpe of the Flanders Marine Institute, David Van Rooij of the Renard Centre of Marine Geology at Ghent University, and Paul Wintersteller and Claudia Wienberg, again of the Center for Marine Environmental Sciences at the University of Bremen, describe a new Cold-water Coral Mound Province on the northwest coast of Morocco.

Coral Mounds were first observed in this area in 2002 during an expedition by the Research Vessel Belgica, and were the revisited in 2014 by the Research Vessel Maria S. Merian, with the objective of mapping their extent, using a KONGSBERG EM122 multibeam echosounder system. A total area of 1440 km² was mapped using ESRI ArcGIS™ v.10.

Hebbeln et al. found a total of 3463 Coral Mounds within the 1440 km² study area, giving an average density of 2.4 mounds per km². These mounds were found at depths of between 565 and 1155 m, though most were concentrated in two bands, between 890 m and 980 m and between 720 and 870 m, with the shallower band being home to about 59% of the mounds and the deeper band to about 24%. These bands were found on areas where the continental slope had an inclination of about 2-3°, while the area between the bands had an inclination of less than 1°. About 4% of the mounds were found in the area between the two bands, another 4% were found deeper than the deeper band, with about 10% found in waters shallower than the shallower band.

(A) Bathymetric map of the Atlantic Moroccan Coral Mound Province (AMCP) off northwest Morocco, indicated as site 1 in the overview map shown in (B). In the northeast part of the area (grey shaded), Coral Mounds are present within the El Arraiche mud volcano province restricted to water depths of 500-700 m. In water depths deeper than 700 m, coral mounds are mostly arranged along two slope-parallel belts, which follow distinct depth levels (shallow belt: 720-870 m, orange dotted line; deep belt: 890-980, red dotted line). In addition, several large mud volcanoes (MV), one mud diapir (MD), and two fault lines belonging to the South Western Iberian Margin (SWIM) fault system (white dashed lines) are indicated. (B) Overview map of the northwest African margin showing known Coral Mound Provinces (red/orange boxes). (1) Atlantic Moroccan Coral Mound Province (red box - this study), (2) West and East Melilla Coral Mound Provinces in the southern Alboran Sea, (3) Eugen Seibold Coral Mound Province north of the Agadir Canyon, (4) Giant Mauritanian Coral Mound Province. Hebbeln et al. (2019).

The Coral Mounds range in length from 24 to 2075 m, in width from 12 m to 584 m, and in height from 4 m to 50 m (though it was possible to measure the height of only a limited number of Mounds). This means that the individual mounds cover areas of between 300 m² and 950 000 m², though most were towards the smaller end of this range, with only 20 exceeding 120 000 m². The majority of the mounds are elongate in shape, extending downslope rather than along the contour lines. There was no clear correlation between the depth, size and orientation of the Coral Mounds.

An acoustic bathymetric study of part of the area revealed that in an area where 166 Coral Mounds visible above the seafloor were present, there were a total of 615 buried Mounds. If this can be accurately extrapolated to the whole province it would imply that in addition to the 3463 visible Mounds, there should be about 12 500 buried Mounds, suggesting that there are about 16 000 Coral Mounds on the northwest coast of Morocco in total.

(A) Still photograph showing the surface of a Coral Mound of the Atlantic Moroccan Coral Mound Province taken by the Remotely Operated Vehicle Cherokee operating from the Research Vessel Pelagia. The surface of this Mound is covered by dead/fossil Coral framework. (B) PARASOUND sub-bottom profile showing exposed and buried Coral Mounds of the Atlantic Moroccan Coral Mound Province. The Mounds root on multiple horizons pointing to several Mound formation periods during the past. The small box highlights the reflection pattern associated with selected Coral Mounds. Hebbeln et al. (2019).

The approximately 140 m offset between bands of Coral Mounds has been observed before off the coasts of Ireland (where the gap averages about 200 m) and Mauritania (where it is about 150 m). This pattern, with gaps of 140-200 m, is remarkably similar to the estimated difference in sea level during Pleistocene glaciations and warm periods. However the Corals are not thought to have grown at both these times, with Coral growth in the cooler waters off the coast of Ireland thought to have been restricted to warmer interglacial periods, while that in the warmer waters of Morocco and Mauritania is thought to have taken place during periods of glaciation.

Hebbeln et al. estimate that the Coral Mounds, exposed and buried, have an average volume of 84 000 m³, so that the ~16 000 Mounds have a total volume of 1344 km³, including a high proportion of carbonate produced by the Corals, potentially a total of 700 million tons of carbonate, which in turn equates to 84 million tons of carbon, making the Mounds an important carbon sink. If the Coral Mounds have accumulated in the last 900 000 years, with that accumulation going on only during periods of glaciation during that time (about 450 000 years), then the mounds would have accumulated carbonate at a rate of 1550 tons per year across the Atlantic Moroccan Coral Mound Province during periods of active accumulation. This equates to a carbon sink taking 1200 grams of carbon per metre squared every year, which when compared by the rates achieved by boreal peatlands (20 carbon per metre squared every year) or boreal forests (44 carbon per metre squared every year), suggests that the Mounds play an important role in global atmospheric carbon budgets.

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Heliopora hiberniana: A second species of reef-building Octocoral from north Western Australia.

Scleractinian Corals are first appeared around the end of the Ordovician, and since the Triassic have been the major component of Coral Reefs around the world. However, these Corals appear to be threatened today by rising sea temperatures and novel pathogens, both of which have caused widespread bleaching (loss of symbiotic zooxanthellae) and Coral dieback, with potentially disastrous consequences for reef-dwelling communities, which rely on these Corals to build and maintain these habbits. However, there is a single non-Scleractinian reef-building Coral alive today, the sole species of the reef-building Octocoral group, Helioporidae. Heliopora coerulea is present on many reefs today, and forms the dominant constructing species on a number of Pacific Reefs, including Boliano Reef in the Phillippines, Shiraho Reef in Japan, Bikini Atoll in the Marshall Islands, and Tarawa Atoll in Kiribati. This species, known as the Blue Coral due to its distinctive blue skeleton, has apparently been around since the Cretaceous, when fossils identical to the modern form begin to appear. Importantly, the Blue Coral is apparently immune to bleaching, and populations of Blue Corals have survived a number of bleaching incidents in which Scleractinian Corals on the same reefs were more-or-less wiped out.

In a paper published in the journal Scientific Reports on 26 October 2018, Zoe Richards of the Western Australian Museum and the Trace and Environmental DNA Laboratory at Curtin University, Nina Yasuda of the Organization for Promotion of Tenure Track at University of Miyazaki, Taisei Kikuchi of Parasitology at the University of Miyazaki, Taryn Foster of the Australian Institute of Marine Science, Chika Mitsuyuki of the Field Science Center at Tohoku University, Michael Stat, also of the Trace and Environmental DNA Laboratory at Curtin University, and of the Department of Biological Sciences at Macquarie University, Yoshihisa Suyama, also of the Field Science Center at Tohoku University, and Nerida Wilson, also of the Western Australian Museum and the University of Western Australia, describe a second species of Heliopora from the reefs of northern Western Australia.

Octocorals are colonial Corals, Anthozoa, usually lacking the extensive mineralised skeletons of Stony Corals. Each polyp of the colony has only eight tentacles, giving the group its name, though these often have numerous side branches, giving them a feathery appearance.

The new species is named Heliopora hiberniana, in reference to Hibernia Reef, where it was first discovered during a survey of Corals on the reef. The first specimens were noticed because, while they resembled Heliopora coerulea in form they had a white, rather than a blue skeleton. Subsequent DNA analysis of these Corals found that while Heliopora coerulea always has a blue skeleton, Heliopora hiberniana can have either a blue or a white skeleton.

Heliopora hiberniana growing in situ on Hibernia Reef. (A) Branching clump growing in close association with Halimeda sp., (B) Small branching clump. (C) Heliopora hiberniana (top) growing in situ with Heliopora coerulea (bottom) at the type locality. (D) Heliopora hiberniana. with a broken branch showing the white skeleton, (E) Side attached open branching colony with encrusting base; (F) Heliopora hiberniana (background) growing in situ with Stylophora pistillata in the foreground. Richards et al. (2018).

Heliopora hiberniana forms tightly branching clumps up to 40 cm in diameter, with main branches club-shaped and up to 30 cm in length. The branches are rounded, but tend to flatten towards their tips. The species has been found Hibernia Reef, Ashmore Reef, Browse Island, and Scott Reef, off the coast of northern Western Australia; it is unclear to what extent (if any) it is found elsewhere. The observed specimens were living at depths of between one and twelve meters.

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Adelogorgia osculabunda, Adelogorgia hannibalis & Adelogorgia adusta: Three new species of Gorgonian from Costa Rica and Panama.

Octocorals are colonial Corals, Anthozoa, lacking the extensive mineralized skeletons of Stony Corals. Each polyp of the colony has only eight tentacles, giving the group its name, though these often have numerous side branches, giving them a feathery appearance. Gorgonians are a group of Octocaorals that tend to form fan shaped colonies in shallow environments with strong currents. The genus Adelogorgia currently contains two species, one from Baja California and one from the Galapagos Islands.

In a paper published in the journal Zootaxa on 5 January 2018, Odalisca Breedy of the Centro de Investigación en Estructuras Microscópicas at the Universidad de Costa Rica, and Hector Guzman of the Smithsonian Tropical Research Institute, describe three new species of Adelogorgia from the Pacific coasts of Costa Rica and Panama.

The first new species described is named Adelogorgia osculabunda, meaning 'the one that covers with kisses' in reference to the mouths of the polyps, which have distinctive red lips. This species forms fan shaped colonies reaching about 15 cm in height and about 15 cm in width, with two stems rising from a holdfast then dichotomously branching (branching by repeatedly splitting in two). These colonies are pink in colour, with prominent red polyp mounds. The species was found living at depths of between 40 and 60 m along the Pacific coast of Costa Rica, and at a depth of about 80 m in the Pearl Islands, off the Pacific coast of Panama.

Adelogorgia osculabunda, colony. Breedy & Guzman (2018).

The second species is named Adelogorgia hannibalis, meaning 'from Hannibal' in reference to Hannibal Bank, a coastal guyot-type seamount off the Pacific coast of Panama, within the Coiba National Park. This species also forms fan-shaped colonies, reaching about 18 cm in height and 16 cm in width, and orange in colour. This species is known only known from Hannibal Bank, where it was found growing at depths of between 180 and 200 m.

Adelogorgia hannibalis, colony. Breedy & Guzman (2018).

The third new species is named Adelogorgia adusta, meaning 'burnt', as it has a burnt or scorched appearance. This species forms bushy colonies up to 11 cm high and 13 cm across, red and orange in colour. This species was also found on Hannibal Bank, at depths of between 73 and 94 m.

Adelogorgia hannibalis, colony. Breedy & Guzman (2018).

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Analysing the distribution of shallow-water Black Corals in the Hawaiian Archipelago.

Black Corals, Antipatharia, are Anthozoan Hexacorallid Corals known from across the world’s oceans, particularly in waters below the photic zone, waters shallower than about 50 m where light levels are high and attached benthic communities are dominated by photosynthetic organisms, such as Macroalgae (Seaweeds) and Coral species which host symbiotic single-celled Algae, and have been recorded at depths below 8600 m in the Western Pacific. All Black Corals are colonial, they have largely proteinaceous skeletons with minute spines, mouths surrounded by eight non-retractable tentacles and stomachs with eight mesentery canals (single-ended digestive canals which much be emptied of waste matter by periodic eversion). Because most Black Corals live at depths where surveys by Scuba divers are impossible, very little is known about their distributions, with most species known only from single records, though in some areas where shallow-water Black Corals occur better records exist.

One area where such shallow-water Black Corals are abundant is the Hawaiian Archipelago. Here Black Corals are of some economic significance, having been used in traditional Hawaiian medicine, and with a commercial harvesting industry which collects Black Corals for the jewellery industry (Black Coral is the official State Gemstone of Hawaii). As such a large number of surveys of Black Corals at shallow depths have been carried out in Hawaii, although these are generally local in nature and concentrated around the inhabited islands in the southeast of the archipelago.

In a paper published in the journal Marine Biodiversity Records on 17 April 2015, Daniel Wagner of the NOAA’s Papahānaumokuākea Marine National Monument publishes an analysis of the distribution of shallow-water Black Coral species from the Hawaiian Archipelago, based upon collected surveys from the harvesting industry, collection records from museum specimens, and photographic and video records from submersible surveys carried out by the Hawai‘i Undersea Research Laboratory and Monterrey Bay Aquarium Research Institute as well as published records in scientific literature.

For the purpose of this study ‘shallow-water’ was defined as less than 150 m from the surface, the base of the mesophotic zone (the zone below the photic zone where photosynthesis is not carried out but the water is not in permanent darkness) in the clear waters of Hawaii. A total of eight species of Black Corals were recorded, though since the surveying was somewhat patchy in the northern part of the islands this cannot be concluded to be an exhaustive list of the species present. All species grow attached to hard substrates and favour areas of high currents; it is likely that the current affects the distribution of these Corals, but sufficient records were not available to include this in the survey.

The first species recorded is Antipathes griggi, a commercially significant species found throughout the islands from Hawai‘i to Pearl and Hermes Atoll at depths of between nine and 110 m, but most abundant between forty and fifty meters and fairly rare below sixty meters. The species was found to tolerate temperatures of 22.30-27.41˚C, and has a dense bushy crown which extends into the current flow.

(Left) Growing specimen of Antipathes griggi. (Right) The known distribution of the species within the Hawaiian Archipelago. Wagner (2015).

The second species recorded is Antipathes grandis, another commercially important species which is found from from Hawai‘i to Ni‘ihau at depths of depths of between 24 and 146 m, but which is most abundant between 90 and 110 m, and fairly uncommon shallower than 50 m or deeper than 120 m. This species also has a dense bushy crown, and lives at temperatures of 20.01-26.91˚C.

(Left) Growing specimen of Antipathes grandis. (Right) The known distribution of the species within the Hawaiian Archipelago. Wagner (2015).

The third species recorded is Cirrhipathes cf. anguina (i.e. probably Cirrhipathes anguina a specimen cannot actually be confirmed as belonging to a species without comparing it to the holotype – first specimen described – which with some older species, such as Cirrhipathes anguina which was described in 1846, is not always possible) which is found from across the archipelago from Hawai‘i to the north-west of Brooks Banks at depths of between nine and 150 m, although it is less common below 60 m. Cirrhipathes cf. anguina is a wire Coral (i.e. its colonies consist of a single wire-like strand) found at temperatures of 21.92-27.69˚C.

(Left) Growing colonies of Antipathes grandis. (Right) The known distribution of the species within the Hawaiian Archipelago. Wagner (2015).

The fourth species recorded is Stichopathes echinulata, which is found across the archipelago from Hawai‘i to Lisianski, at recorded depths of 90-150 m, and probably also deeper than it was possible to evaluate using the records available for this study. Stichopathes echinulata forms unbranching wire-shaped colonies and lives at temperatures of 19.59-22.91˚C.

(Left) Growing colony of Stichopathes echinulata being manipulated by the arm of a submersible. (Right) The known distribution of the species within the Hawaiian Archipelago. Wagner (2015).

The fifth Coral species recorded is Stichopathes? sp. (an unidentified species of Coral which probably belongs to the genus Stichopathes) which was found from Hawai‘i to French Frigate Shoals at depths of 9-58 m, though it was never abundant. This species also forms unbranching wire colonies, though insufficient data was available to determine its temperature preferences.

(Left) Growing colonies of Stichopathes? sp. (Right) The known distribution of the species within the Hawaiian Archipelago. Wagner (2015).

The sixth Coral species recorded is Aphanipathes verticillata, which has been found only in the Keyhole Pinnacle area of the Au‘au Channel, at depths of 88-130 m. This species forms flat branching colonies and is found at a temperature range of 19.88-22.96˚C. The Hawaiian population of Aphanipathes verticillata was only discovered in 2008, and is thought to be a distinct subspecies, Aphanipathes verticillata mauiensis, though it closely resembles the related Antipathes griggi, and cannot be differentiated without close examination of the polyps, making it likely that many older surveys have failed to identify this species, and that it is more widely distributed within the Hawaiian Archipelago than is currently appreciated. Other populations of Aphanipathes verticillata are known from Mauritius and Okinawa, which supports the idea of this species being more widely distributed.

(Left) Growing colonies of Aphanipathes verticillata mauiensis. (Right) The known distribution of the species within the Hawaiian Archipelago. Wagner (2015).

The seventh species of Coral recorded is Acanthopathes undulata, which is found across the archipelago from Hawai‘i to Laysan at depths of 32-150 m, although it is more common below 100 m. Acanthopathes undulata forms branching colonies. It was not possible to establish a range of temperature preferences for this study.

(Left) Growing colonies of Acanthopathes undulata. (Right) The known distribution of the species within the Hawaiian Archipelago. Wagner (2015).

The final species recorded was Myriopathes cf. ulex, which is a commercially exploited species found across the archipelago from 30-150 m; it is more commonly recorded at depths of 60 m or shallower, though this may reflect the limit of harvesting potential rather than the true distribution of colonies, and the species may also be present deeper than 150 m, the limit of the survey. Myriopathes cf. ulex forms densely branching fan-shaped colonies, and has a temperature range of 20.52-26.99˚C.

(Left) Growing colonies of Myriopathes cf. ulex. (Right) The known distribution of the species within the Hawaiian Archipelago. Wagner (2015).

All of the Coral species examined in this study had depth and temperature ranges which overlapped with other species. Nevertheless there was clear separation in the habitat preferences of these species, particularly in mean temperature (the average temperature at which colonies were found), with Antipathes griggi colonies found in waters with an average temperature of 26.25˚C, Cirrhipathes cf. anguina having a mean temperature of 26.27˚C, Antipathes grandis 24.25˚C, Myriopathes cf. ulex 22.56˚C, Aphanipathes verticillata 21.19˚C and Stichopathes echinulata 21.08 ˚C. Furthermore, where species pairs had close mean temperature preferences, such as Antipathes griggi and Cirrhipathes cf. anguina or Aphanipathes verticillata and Stichopathes echinulata, they quite often had very different polyp sizes, suggesting that they were exploiting different resources. It is very likely that the distribution of these Corals is affected by other factors, such as current speeds and food supply (i.e. the amount of edible food in the water passing over them), but these were beyond the scope of the current study.

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A new species of Soft Coral from the Republic of Congo.

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A new species of Anthazoan Coral from the Abrolhos Archipelago and Royal Charlotte Bank, Brazil.

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Two new species of Zoanthid Coral from Australia and Japan.

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A new species of Anthazoan Coral from the Abrolhos Archipelago and Royal Charlotte Bank, Brazil.

The Abrolhos Bank is an area of the Brazilian continental shelf to the south of Bahia State, noted for its large and rich coral reef fauna and unique geochemical nature, with high levels of siliclastic material (sand, quartz gravel etc.) being deposited in the area by the Brazil Current, which flows southward from the coast. The area includes the Abrolhos Archipelago, which is Brazil’s oldest marine reserve.

In a paper published in the journal Zootaxa on 4 July 2014, Sérgio Stampar of the Departamento de Ciências Biológicas at the Universidade Estadual Paulista and the Departamento de Zoologia at the Universidade de São Paulo, and André Morandini and Fábio Lang da Silveira, also of the Departamento de Zoologia at the Universidade de São Paulo, describe a new species of Anthazoan Coral from Abrolhos Archipelago and Royal Charlotte Bank on the Abrolhos Bank.

The new species is placed in the genus Pachycerianthus, and given the specific name schlenzae, in honour of Erika Schlenz formerly of the Departamento de Zoologia at the Universidade de São Paulo, and a well-known expert on Corals. Pachycerianthus schlenzae is a solitary Coral reaching about 15 cm in height, with 60-85 marginal tentacles reaching about 12 cm in length plus 60-80 labial tentacles, reaching about 4 cm. The tentacles are brown or purple with white spots.

Pachycerianthus schlenzae, live specimens. (A) From Guarapari in Espirito Santos State. (B) From Camamu Bay in Bahia State. Stampar et al. (2014).

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 Two new species of Zoanthid Coral from Australia and Japan.

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 Five new species of deepwater Corals from the South American continental shelf.

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 The vanishing Corals of Pelorus Island.

Corals on Australia's Great Barrier Reef, as in other parts of the world, are known to be in trouble, with declining Coral coverage, diebacks, bleaching events and replacement of Corals by Macroalgae (Seaweed) on much of the reef. Unfortunately, recording of Coral...

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