Black Coral Research Articles

Newspeciesofblackcorals(Cnidaria:Anthozoa:Antipatharia)fromdeep-seaseamountsandridgesinthe NorthPacific.

Three new species of antipatharian corals are described from deep-sea (677-2,821 m) seamounts and ridges in the North Pacific, including Antipathes sylospongia, Alternatipathes venusta, and Umbellapathes litocrada. Most of the material for these descriptions was collected on expeditions aboard NOAA Ship Okeanos Explorer that were undertaken as part of the Campaign to Address Pacific Monument Science, Technology, and Ocean Needs (CAPSTONE). One of the main goals of CAPSTONE was to characterize the deep-sea fauna in protected waters of the U.S. Pacific, as well as in the Prime Crust Zone, the area with the highest known concentration of commercially valuable deep-sea minerals in the Pacific. Species descriptions and distribution data are supplemented with in situ photo records, including those from deep-sea exploration programs that have operated in the North Pacific in addition to CAPSTONE, namely the Hawaii Undersea Research Laboratory (HURL), the Ocean Exploration Trust (OET), and the Monterey Bay Aquarium Research Institute (MBARI).

Unveiling asexual reproductive traits in black corals: polyp bail-out in Antipathella subpinnata

Cnidarians are known to undergo reverse development as a survival mechanism against adverse environmental conditions. Polyp bail-out consists in the polyps’ detachment from the mother colony due to stressful conditions, followed by a complete tissue and cells rearrangement and in some cases in a regression into a simple, ciliated form. Here we describe a massive polyp bail-out event occurred in the mesophotic black coral Antipathella subpinnata in reared conditions. This is the first report of a bail-out event in this species providing new insights into the life cycle and ecology of black corals.

Local Conditions Influence the Prokaryotic Communities Associated With the Mesophotic Black Coral Antipathella subpinnata.

Black corals are important habitat-forming species in the mesophotic and deep-sea zones of the world’s oceans because of their arborescent colony structure and tendency to form animal forests. Although we have started unraveling the ecology of mesophotic black corals, the importance of the associated microbes to their health has remained unexplored. Here, we provide in-depth assessments of black coral-microbe symbioses by investigating the spatial and temporal stability of these associations, and make comparisons with a sympatric octocoral with similar colony structure. To this end, we collected samples of Antipathella subpinnata colonies from three mesophotic shoals situated along the Ligurian Coast of the Mediterranean Sea (Bordighera, Portofino, Savona) in the spring of 2017. At the Portofino shoal, samples of A. subpinnata and the gorgonian Eunicella cavolini were collected in November 2016 and May 2017. Bacterial communities were profiled using 16S rRNA gene amplicon sequencing. The bacterial community of E. cavolini was consistently dominated by Endozoicomonas. Contrastingly, the black coral microbiome was more diverse, and was primarily composed of numerous Bacteroidetes, Alpha- and Gammaproteobacterial taxa, putatively involved in all steps of the nitrogen and sulfur cycles. Compositional differences in the A. subpinnata microbiome existed between all locations and both time points, and no phylotypes were consistently associated with A. subpinnata. This highlights that local conditions may influence the bacterial community structure and potentially nutrient cycling within the A. subpinnata holobiont. But it also suggests that this coral holobiont possesses a high degree of microbiome flexibility, which may be a mechanism to acclimate to environmental change.

Testing Side-Scan Sonar and Multibeam Echosounder to Study Black Coral Gardens: A Case Study from Macaronesia

Black corals (order Antipatharia) are important components of mesophotic and deep-water marine communities, but due to their inaccessibility, there is limited knowledge about the basic aspects of their distribution and ecology. The aim of this study was to test methodologies to map and study colonies of a branched antipatharian species, Antipathella wollastoni, in the Canary Islands (Spain). Acoustic tools, side-scan sonar (SSS), and a multibeam echosounder (MBES), coupled with ground-truthing video surveys, were used to determine the habitat characteristics of Antipathella wollastoni. Below 40 m depth, colonies of increasing height (up to 1.3 m) and abundance (up to 10 colonies/m2) were observed, particularly on steep and current-facing slopes on rocky substrates. However, coral presence was not directly imaged on backscatter mosaics and bathymetric data. To improve this situation, promising initial attempts of detecting Antipathella wollastoni by utilizing the MBES water column scatter in an interval for 0.75 m to 1 m above the seafloor are reported.

Shallow-water black corals (Cnidaria: Anthozoa: Hexacorallia:Antipatharia) from SW Madagascar.

Antipatharians, also known as black corals, represent a small group of anthozoan hexacorallians found in all oceans of the world. They are generally considered a deep-water taxon; however, some of the most diverse communities are known from tropical shallow waters. With a few poorly detailed exceptions, shallow-water black corals from the Indian Ocean and especially those from Madagascar are mostly unknown. In this study, we report for the first time a highly diverse black coral assemblage of the Western Indian Ocean thriving in shallow waters and upper mesophotic depths (10-52 m depth) along the SW coast of Madagascar. A total of 22 species belonging to six genera (Antipathes, Arachnopathes, Cirrhipathes, Cupressopathes, Myriopathes and Stichopathes) and two families (Antipathidae and Myriopathidae) are described, of which 20 are found in the northern pass of the Great Reef of Toliara, thus representing the most diverse site of the areas investigated. Most of the shallow-water species from the Indian Ocean were originally described more than a century ago, sometimes without being reported again until now. All the descriptions herein rely solely on morphology and include detailed in situ pictures and scanning electron microscope images, in addition to range expansions for many species.

Feeding biology of a habitat-forming antipatharian in the Azores Archipelago

Benthic suspension feeders have developed a variety of feeding strategies and food availability has often proven to be a key factor explaining their occurrence and distribution. The feeding biology of coral species has been the target of an increasing number of studies, however most of them focus on Scleractinia and Octocorallia, while information for Antipatharia is very scarce. The present study focused on Antipathella wollastoni, a common habitat-forming antipatharian in the Azores Archipelago, forming dense black coral forests between 20 and 150 m. The objective of the study was to investigate the food preferences of the target species upon availability of different isotopically enriched food substrates and determine its ability to capture zooplankton prey under different flow speeds. The species was able to utilize different food sources including live phytoplankton, live zooplankton and dissolved organic matter (DOM), indicating the ability to exploit seasonally available food sources. However, ingestion of zooplankton enhanced carbon (C) and nitrogen (N) incorporation in coral tissue and metabolic activity, highlighting the importance of zooplankton prey for vital physiological processes such as growth and reproduction. Maximum zooplankton capture rates occurred under 4 cm−1, however the species displayed high capacity to capture zooplankton prey over different flow rates highlighting the ability of A. wollastoni to exploit high quantities of shortly available prey.

Morphological and molecular description of a new genus and species of black coral (Cnidaria: Anthozoa: Hexacorallia: Antipatharia: Antipathidae: Blastopathes) from Papua New Guinea.

Blastopathes medusa gen. nov., sp. nov., is described from Kimbe Bay, Papua New Guinea, based on morphological and molecular data. Blastopathes, assigned to the Antipathidae, is a large, mythology-inspiring black coral characterized by clusters of elongate stem-like branches that extend out at their base and then curve upward. Colonies are not pinnulate and contain single branches, which could represent new branch cluster formations. Morphological and molecular (mitochondrial DNA and targeted capture of nuclear loci) evidence supporting the establishment of a new genus is discussed. This is the first study to utilize the target capture of ultraconserved elements (UCEs) and exonic loci to elucidate phylogenetic relationships among black corals and to identify and place a new genus and species.

Social-Cultural Impact of Bead work in East Africa: the Nexus between the Dinka, Samburu & Masaai Ethnicities

Beadwork has been practiced in Africa and worldwide for centuries. In East Africa, different communities made beads from a wide range of materials available to them. This materials range from black coral collected from the Indian Ocean to the use of bone from their livestock. This study is an analysis of beadwork uses in the following East African communities; Dinka of South Sudan, Maasai of Kenya and Tanzania, and the Samburu of Kenya. Conducted in Nairobi, the objective was to establish its social-cultural significance as an art form. It was also a part of the annual design symposia, workshops and presentations involving master's students, faculty, experts and stakeholders. The research used an interview guide, observation and a historical research method. The findings established that beadwork was used for social, cultural and religious practices in all the communities. These include, rites of passage, decoration and ornamentation, and also for political and leadership purposes. Despite the similarities in occasions, the types, and colors of beads used differed. The findings further pointed out the unique characteristics in color, materials, shape of beads in each community.

Phylogenetics and Mitogenome Organisation in Black Corals (Anthozoa: Hexacorallia: Antipatharia): An Order-Wide Survey Inferred From Complete Mitochondrial Genomes

Black corals (Anthozoa: Antipatharia) are an ecologically and culturally important group of deep-sea cnidarians. However, as the majority of species inhabit depths >50 m, they are relatively understudied. The inaccessibility of well-preserved tissue for species of interest has limited the scope of molecular analysis, and as a result only a small number of antipatharian mitochondrial genomes have been published. Using next generation sequencing, eighteen complete and five partial antipatharian mitochondrial genomes were assembled, increasing the number of complete mitochondrial genomes to twenty-two. This includes species from six antipatharian families, four of which were previously unrepresented, enabling the first family-level, full mitochondrial gene analysis over the whole order. The circular mitogenomes ranged in size from 17681 to 21669 bp with the large range in size due to the addition of an intron in COX1 in some species and size variation of intergenic regions. All mitogenomes contained the genes standard to all hexacoral mitogenomes (13 protein coding genes, two rRNAs and two tRNAs). The only difference in gene content is the presence of the COX1 intron in five families. The most variable mitochondrial gene is ND4 which may have implications for future barcoding studies. Phylogenetic analysis confirms that Leiopathidae is sister to all other families. Families Antipathidae, Cladopathidae and Schizopathidae are polyphyletic, supporting previous studies that call for a taxonomic revision.

Ageing Deep-Sea Black Coral Bathypathes patula

Deep-sea corals are a highly diverse group of marine organisms, several of which are characterised by slow growth and extreme longevity up to thousands of years. Due to their fragile forms, skeletal composition, and location, they are vulnerable to various anthropogenic threats, with some groups expected to have little to no ability to recover. Within the New Zealand region an understanding of age and growth parameters and recovery potential for some deep-sea coral fauna is being developed, but a limited understanding remains for some of the key Antipatharian black coral fauna. Ten individual colonies of the black coral species Bathypathes patula were sourced from the National Institute of Water and Atmospheric Research Invertebrate Collection for the purposes of this age estimation study. Corals were selected based on their size, completeness of the colony (whole colony from base to tip), and the regional water mass within which they grew. Coral samples from the Chatham Rise, east of New Zealand, and the Bay of Plenty, north-eastern New Zealand, were selected as the water masses for these two regions are reasonably well understood. Thin section preparations of the main stem of the 10 specimens of B. patula were observed with compound microscopes. Two interpretation protocols were used to describe the zone structures observed, both the coarse wide zones and the thin fine zones, and counts were then made of these structures. Four of the specimens were also sampled for radiocarbon assay. The radiocarbon isotope (14C) age data results were used to independently verify if either of the developed zone counting protocols reflected annual periodicity. Neither method was verified, indicating zone counting protocols could not be used to generate reliable age estimates for B. patula. Twenty radiocarbon assays from four specimens were used to derive the age and growth rate estimates presented here. The radiocarbon results from this work show B. patula to be a long-lived species, attaining ages in excess of 385 years, with linear growth rates of 5.2-9.6 mm/yr, and radial growth rates ranging from 11.1 to 35.7 mm/yr. The delicate nature of these organisms along with their longevity and slow growth rates means a low resilience and low recoverability from anthropogenic activities such as fishing and mining.

From five to one: Sandyella species (Palaemonidae) are distinct ontogenetic stages of a single species

AbstractThe palaemonid genus Sandyella includes S. tricornuta (Isla María Madre, Mexico), S. mclaughlinae, S. bicornuta, S. quadricornuta and S. sexicornuta (Clipperton Island, France). These species were first described in the genus Chacella based on collections of few individuals and limited to no ecological information. Sandyella was later erected to differentiate Chacella kerstitchi from Chacella tricornuta and Chacella mclaughlinae. The remaining three Chacella species (<3 mm cephalothorax length) were later also moved to Sandyella and distinguished mainly based on variation in the less than three protuberances on the cephalothorax and number of protuberances on the abdomen. Since their description from their type localities, only Sandyella tricornuta has been additionally recorded from Bahía de La Paz, Mexico. Collections done at 13 locations along the Gulf of California (2009–2010) yielded 2,905 specimens including representatives of all Sandyella species as epibionts of 57 black coral colonies Antipathes galapagensis, which prompted a closer taxonomic examination. Based on observations of live and preserved specimens, including type material, population cephalothorax size frequency and mitochondrial COI data, we inferred that all current Sandyella species (a) exhibit three protuberances on the cephalothorax; (b) cephalothorax length and number of protuberances appear to be progressive among species; (c) species exhibit high COI sequence similarity; and d) the five Sandyella species were observed cohabiting the same black coral colony. Therefore, we conclude that the five current Sandyella species are in fact distinct ontogenetic stages of a single species, S. tricornuta, and our results of a morphological Bayesian analysis led us conclude that this species belongs to the genus Sandyella rather than Chacella.

Electrochemical Approach for Isolation of Chitin from the Skeleton of the Black Coral Cirrhipathes sp. (Antipatharia).

The development of novel and effective methods for the isolation of chitin, which remains one of the fundamental aminopolysaccharides within skeletal structures of diverse marine invertebrates, is still relevant. In contrast to numerous studies on chitin extraction from crustaceans, mollusks and sponges, there are only a few reports concerning its isolation from corals, and especially black corals (Antipatharia). In this work, we report the stepwise isolation and identification of chitin from Cirrhipathes sp. (Antipatharia, Antipathidae) for the first time. The proposed method, aiming at the extraction of the chitinous scaffold from the skeleton of black coral species, combined a well-known chemical treatment with in situ electrolysis, using a concentrated Na2SO4 aqueous solution as the electrolyte. This novel method allows the isolation of α-chitin in the form of a microporous membrane-like material. Moreover, the extracted chitinous scaffold, with a well-preserved, unique pore distribution, has been extracted in an astoundingly short time (12 h) compared to the earlier reported attempts at chitin isolation from Antipatharia corals.

Morphological and molecular characterization of a new species of black coral from Elvers Bank, north-western Gulf of Mexico (Cnidaria: Anthozoa: Hexacorallia: Antipatharia: Aphanipathidae: Distichopathes)

AbstractThe continental shelf edge of the NW Gulf of Mexico supports dozens of reefs and banks, including the West and East Flower Garden Banks (FGB) and Stetson Bank that comprise the Flower Garden Banks National Marine Sanctuary (FGBNMS). Discovered by fishermen in the early 1900s, the FGBs are named after the colourful corals, sponges and algae that dominate the region. The reefs and banks are the surface expression of underlying salt domes and provide important habitat for mesophotic coral ecosystems (MCE) and deep coral communities to 300 m depth. Since 2001, FGBNMS research teams have utilized remotely operated vehicles (e.g. ‘Phantom S2’, ‘Mohawk’, ‘Yogi’) to survey and characterize benthic habitats of this region. In 2016, a Draft Environmental Impact Statement proposed the expansion of the current sanctuary boundaries to incorporate an additional 15 reefs and banks, including Elvers Bank. Antipatharians (black corals) were collected within the proposed expansion sites and analysed using morphological and molecular methods. A new species, Distichopathes hickersonae, collected at 172 m depth on Elvers Bank, is described within the family Aphanipathidae. This brings the total number of black coral species in and around the sanctuary to 14.

A mesophotic black coral forest in the Adriatic Sea

A forest of the black coral Antipathella subpinnata was found from 52 to 80 m depth in three different sites at Tremiti Islands Marine Protected Area (MPA; Mediterranean Sea), with two of them hosting a monospecific forest on horizontal and vertical substrates. Colonies of A. subpinnata showed a mean density between 0.22 ± 0.03 and 2.40 ± 0.26 colonies m−2 (maximum local values of 2.4–7.2 colonies m−2). The link between the local distribution of A. subpinnata and the main oceanographic features confirmed the fundamental role of the currents in shaping the distribution of the species in presence of hard substrata. This black coral forest represents the only one known thus far in the Adriatic Sea, but it could be linked with other unseen forests all over the Mediterranean Sea. The associated megafauna highlights the importance of these forests as habitat for species of both conservation and commercial importance but, at the same time, makes such habitat a target for fishing practices, as many lost fishing gears were found within the coral forest. The enlargement of the MPA borders and the enforcement of controls in the area of the A. subpinnata forest is urgently needed for the proper conservation of this protected species.

Growth and longevity of New Zealand black corals

Deep-sea corals are an important component of benthic ecosystems, but are potentially very vulnerable to ecological disturbance due to their extreme longevity and slow growth rates. Among the slowest growing genera are the ‘Black Corals’ (Family Antipatharia), which can have lifespans of millennia. The waters around New Zealand contain a variety of black corals, including species that grow at shallow depths in the southern Fjords. However, while growth rates in black corals have been reported for many other parts of the world, New Zealand's black corals have received little attention. Here we present a series of high-resolution radiocarbon dates for coral colonies of the genera Antipathella, Leiopathes and Antipathes. Our results illustrate some corals have lifespans of up to 3000 years and slow but highly variable growth (averaging 10–100 μm/yr) for genera Leiopathes and Antipathes and fast growth (averaging 2–3 cm/yr) for genera Antipathella, with no obvious regional variability in growth rates over time. Our results are broadly consistent with other black coral growth rate studies, and reinforce that New Zealand's black corals likely have low resilience to any disturbance.

Deep-sea Coral Taxonomy Workshop, Colombia 2019

Corals are some of the conspicuous taxa in deep-sea ecosystems. Yet, characterizing coral diversity is difficult and requires a combination of both morphological and genetic data. Many leading coral taxonomy experts are close-to retirement or have already retired. It is now imperative that the hands-on expertise that these taxonomists have – much of which is not captured in manuscripts or books – is transferred to the next generation. The Deep-Sea Coral Taxonomy Workshop, funded by a Lounsbery award from the Deep-Sea Biology Society, aimed to provide a training opportunities and build taxonomic capacity in Colombia and Latin America. Workshop participants examined the deep-sea coral diversity of the southern western Caribbean, a poorly explored region. The three-day workshop was based mainly on hands-on activities focused on octocorals and black corals, and included introductory talks to the taxonomy of these groups and identification activities using specimens. Thanks to the workshop, it was possible to review and update the classification database of the Makuriwa Marine Natural History Museum collection. Additionally, four new species from the families Clavulariidae, Plexauridae and Gorgoniidae were identified and will be described in the near future.

A new distributional record of the black coral Antipathes cf. griggi in Mactan Island, Philippines.

The black coral Antipathes cf. griggi was reported for the first time outside the Hawaiian Archipelago. This short report provides details and short description of the newly recorded species in Mactan Island, Philippines.

The impact of marine litter from fish aggregation devices on vulnerable marine benthic habitats of the central Mediterranean Sea

The aim of this research was to assess marine litter abundance and its effects on the benthic fauna in an area of the central Mediterranean Sea exploited by fisheries using fish aggregating devices (FAD). The study was carried out by means of a remotely-operated vehicle (ROV). Derelict fishing gear, mainly FAD ropes, represented the main source of marine debris, contributing 96.2% to the overall litter. About 47% of debris items (mostly FAD ropes) entangled colonies of the protected black coral Leiopathes glaberrima. The results of this research will assist in the monitoring of “impact/harm” to the coral and other benthic communities, as recommended by the Marine Strategy Framework Directive and by the Integrated Monitoring and Assessment Programme. Preventive and mitigation measures (i.e., biodegradable fishing gear, onboard technology to locate and retrieve gear, reception and/or payment for old/retrieved gear, and introduction of no-take zones) to reduce the problem are discussed.

Compositional variation between high and low prokaryotic diversity coral reef biotopes translates to different predicted metagenomic gene content.

In a previous study, we identified host species that housed high and low diversity prokaryotic communities. In the present study, we expand on this and assessed the prokaryotic communities associated with seawater, sediment and 11 host species from 7 different phyla in a Taiwanese coral reef setting. The host taxa sampled included hard, octo- and black corals, molluscs, bryozoans, flatworms, fish and sea urchins. There were highly significant differences in composition among host species and all host species housed distinct communities from those found in seawater and sediment. In a hierarchical clustering analysis, samples from all host species, with the exception of the coral Galaxea astreata, formed significantly supported clusters. In addition to this, the coral G. astreata and the bryozoan Triphyllozoon inornatum on the one hand and the coral Tubastraea coccinea, the hermit crab Calcinus laevimanus and the flatworm Thysanozoon nigropapillosum on the other formed significantly supported clusters. In addition to composition, there were highly pronounced differences in richness and evenness among host species from the most diverse species, the bryozoan T. inornatum at 2518 ± 240 OTUs per 10,000 sequences to the least diverse species, the octocoral Cladiella sp. at 142 ± 14 OTUs per 10,000 sequences. In line with the differences in composition, there were significant differences in predicted metagenomic gene counts among host species. Furthermore, there were pronounced compositional and predicted functional differences between high diversity hosts (Liolophura japonica, G. astreata, T. coccinea, C. laevimanus, T. inornatum) and low diversity hosts (Antipathes sp., Pomacentrus coelestis, Modiolus auriculatus, T. nigropapillosum, Cladiella sp. and Diadema savigny). In particular, we found that all tested low diversity hosts were predicted to be enriched for the phosphotransferase system compared to high diversity hosts.

Seasonal variation of the stable C and N isotopic composition of the mesophotic black coral Antipathella subpinnata (Ellis & Solander, 1786)

Trophic relationships significantly influence ecosystem functioning, ultimately affecting populations’ abundance, size structure and distribution. There is still a substantial knowledge gap on the trophic ecology of deep-sea organisms, particularly those living in the mesophotic depths (30–150 m), despite their crucial importance as ecosystem engineers. The trophic ecology of the most common mesophotic black coral species of the Mediterranean Sea, Antipathella subpinnata (Ellis & Solander, 1786), was studied by means of stable isotopes analysis in two seasons. The δ13C and δ15N analysis of the tissue of A. subpinnata, of the sediment, as well as the main planktonic fractions (pico-nanoplankton, microplankton, and mesozooplankton) indicate a diet based on pico-nanoplankton in autumn and mesozooplankton in spring. We calculated a trophic enrichment of 1‰ in δ13C and of 2.5‰ δ15N between prey and predator. Such information contributes towards drawing a complete picture of the pelagic-benthic coupling in the Mediterranean mesophotic coral forests.