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Sample records for octocoral pseudopterogorgia elisabethae

  1. Light-mediated 15N fractionation in Caribbean gorgonian octocorals: implications for pollution monitoring

    Science.gov (United States)

    Baker, D. M.; Kim, K.; Andras, J. P.; Sparks, J. P.

    2011-09-01

    The stable nitrogen isotope ratio ( δ 15N) of coral tissue is a useful recorder of anthropogenic pollution in tropical marine ecosystems. However, little is known of the natural environmentally induced fractionations that affect our interpretation of coral δ 15N values. In symbiotic scleractinians, light affects metabolic fractionation of N during photosynthesis, which may confound the identification of N pollution between sites of varied depth or turbidity. Given the superiority of octocorals for δ 15N studies, our goal was to quantify the effect of light on gorgonian δ 15N in the context of monitoring N pollution sources. Using field collections, we show that δ 15N declined by 1.4‰ over 20 m depth in two species of gorgonians, the common sea fan, Gorgonia ventalina, and the slimy sea plume, Pseudopterogorgia americana. An 8-week laboratory experiment with P. americana showed that light, not temperature causes this variation, whereby the lowest fractionation of the N source was observed in the highest light treatment. Finally, we used a yearlong reciprocal depth transplant experiment to quantify the time frame over which δ 15N changes in G. ventalina as a function of light regime . Over the year, δ 15N was unchanged and increased slightly in the deep control colonies and shallow colonies transplanted to the deep site, respectively. Within 6 months, colonies transplanted from deep to shallow became enriched by 0.8‰, mirroring the enrichment observed in the shallow controls, which was likely due to the combined effect of an increase in the source δ 15N and reduced fractionation. We conclude that light affects gorgonian δ 15N fractionation and should be considered in sampling designs for N pollution monitoring. However, these fractionations are small relative to differences observed between natural and anthropogenic N sources.

  2. Octocoral diseases in a changing ocean

    Science.gov (United States)

    Weil, Ernesto; Rogers, Caroline S.; Croquer, Aldo

    2017-01-01

    Octocorals (Cnidaria, Octocorallia) constitute a geographically widely distributed and common group of marine invertebrates commonly referred to as “soft-corals,” “sea fans,” “horny corals,” “sea feathers,” and “sea plumes.” They are found from shallow coastal habitats to mesophotic and abyssal depths. Octocorals are important members of most Atlantic-Caribbean, Indo-Pacific, and Mediterranean coastal and mesophotic reef communities; however, information about their susceptibility to diseases, predation, and competition, and their relationship with changing environmental conditions is limited. At least 19 diseases have been observed in at least 42 common octocoral species throughout their range. Twelve of these have been reported in the wider Caribbean (CA), one in Brazil (BR), two in the Mediterranean (ME), one in the Eastern Pacific (EP), and three in the western Pacific (WP). Pathogenic and/or environmental causes have been identified for eight diseases, including viruses, terrestrial fungi, protozoans, bacteria and cyanobacteria, filamentous algae, parasitic copepods, and high temperature. Only a few of the suspected pathogens have been tested with Koch’s postulates. At least eight disease outbreaks have led to extensive octocoral mortalities in the CA, ME, BR, and EP with detrimental ecological consequences. The fungal disease Aspergillosis has produced the highest mortalities in the CA and the EP. Other fungi, protozoans, and the bacterium Vibrio coralliilyticus were identified as potential causes of the death of millions of colonies in two Mediterranean disease outbreaks. Bacterial and fungal agents seemed to be responsible for the mass mortalities in Brazil and the WP. Most outbreaks in all regions were linked to high thermal anomalies associated with climate change, which seems to be the major driver. Other biological stressors such as predation and/or competition produce injuries that may contribute to the spread of infections and

  3. Terpenoids from the Octocoral Sinularia gaweli

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    Wun-Jie Lin

    2015-08-01

    Full Text Available Two eudesmane sesquiterpenoids, verticillatol (1 and 5α-acetoxy-4(14-eudesmene-1β-ol (2 and two cembrane diterpenoids, (–-leptodiol acetate (3 and sinulacembranolide A (4 were isolated from the octocoral Sinularia gaweli and compounds 2–4 are new isolates. The structures of new terpenoids 2–4 were elucidated by spectroscopic methods and by comparison the spectral data with those of known analogues. Terpenoid 4 was found to inhibit the accumulation of the pro-inflammatory inducible nitric oxide synthase (iNOS protein of the lipopolysaccharide (LPS-stimulated RAW264.7 marcophage cells.

  4. Energy Budget for the Cultured, Zooxanthellate Octocoral Sinularia flexibilis

    NARCIS (Netherlands)

    Khalesi, M.K.; Beeftink, H.H.; Wijffels, R.H.

    2011-01-01

    The zooxanthellate octocoral Sinularia flexibilis is a producer of potential pharmaceutically important metabolites such as antimicrobial and cytotoxic substances. Controlled rearing of the coral, as an alternative for commercial exploitation of these compounds, requires the study of

  5. Does elevated pCO2 affect reef octocorals?

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    Gabay, Yasmin; Benayahu, Yehuda; Fine, Maoz

    2013-03-01

    Increasing anthropogenic pCO2 alters seawater chemistry, with potentially severe consequences for coral reef growth and health. Octocorals are the second most important faunistic component in many reefs, often occupying 50% or more of the available substrate. Three species of octocorals from two families were studied in Eilat (Gulf of Aqaba), comprising the zooxanthellate Ovabunda macrospiculata and Heteroxenia fuscescens (family Xeniidae), and Sarcophyton sp. (family Alcyoniidae). They were maintained under normal (8.2) and reduced (7.6 and 7.3) pH conditions for up to 5 months. Their biolological features, including protein concentration, polyp weight, density of zooxanthellae, and their chlorophyll concentration per cell, as well as polyp pulsation rate, were examined under conditions more acidic than normal, in order to test the hypothesis that rising pCO2 would affect octocorals. The results indicate no statistically significant difference between the octocorals exposed to reduced pH values compared to the control. It is therefore suggested that the octocorals' tissue may act as a protective barrier against adverse pH conditions, thus maintaining them unharmed at high levels of pCO2.

  6. Report on a few Octocorals from Eniwetok Atoll, Marshall Islands

    NARCIS (Netherlands)

    Verseveldt, J.

    1972-01-01

    In 1969 Dr. Arthur G. Humes, Boston University, Massachusetts, U.S.A., collected a number of octocorals at Eniwetok Atoll, Marshall Islands. He found that most of these corals were the hosts of copepods, just like the corals collected by him in the waters north-west of Madagascar (vide Verseveldt,

  7. Discovery of New Eunicellins from an Indonesian Octocoral Cladiella sp.

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    Chen, Yung-Husan; Tai, Chia-Ying; Su, Yin-Di; Chang, Yu-Chia; Lu, Mei-Chin; Weng, Ching-Feng; Su, Jui-Hsin; Hwang, Tsong-Long; Wu, Yang-Chang; Sung, Ping-Jyun

    2011-01-01

    Two new 11-hydroxyeunicellin diterpenoids, cladieunicellin F (1) and (–)-solenopodin C (2), were isolated from an Indonesian octocoral Cladiella sp. The structures of eunicellins 1 and 2 were established by spectroscopic methods, and eunicellin 2 was found to be an enantiomer of the known eunicellin solenopodin C (3). Eunicellin 2 displayed inhibitory effects on the generation of superoxide anion and the release of elastase by human neutrophils. The previously reported structures of two eunicellin-based compounds, cladielloides A and B, are corrected in this study. PMID:21747739

  8. Natural product antifoulants from the octocorals of Indian waters

    Digital Repository Service at National Institute of Oceanography (India)

    Raveendran, T.V.; LimnaMol, V.P.; Parameswaran, P.S.

    stream_size 22497 stream_content_type text/plain stream_name Int_Biodeterior_Biodegrad_65_265a.pdf.txt stream_source_info Int_Biodeterior_Biodegrad_65_265a.pdf.txt Content-Encoding UTF-8 Content-Type text/plain; charset=UTF-8... 1 Author version: International Biodeterioration & Biodegradation, vol.65(1); 2011; 265-268 Natural Product Antifoulants from the Octocorals of Indian waters T.V. Raveendran * , V.P. Limna Mol, P.S. Parameswaran National Institute...

  9. Octocoral Density for the Florida Keys National Marine Sanctuary from 1999-2009. (NODC Accession 0123059)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Using data collected from 1999 to 2009, the dataset includes species density of benthic octocorals collected from multiple habitat types across the south Florida...

  10. Octocoral Species Assembly and Coexistence in Caribbean Coral Reefs.

    Science.gov (United States)

    Velásquez, Johanna; Sánchez, Juan A

    2015-01-01

    What are the determinant factors of community assemblies in the most diverse ecosystem in the ocean? Coral reefs can be divided in continental (i.e., reefs that develop on the continental shelf, including siliciclastic reefs) and oceanic (i.e., far off the continental shelf, usually on volcanic substratum); whether or not these habitat differences impose community-wide ecological divergence or species exclusion/coexistence with evolutionary consequences, is unknown. Studying Caribbean octocorals as model system, we determined the phylogenetic community structure in a coral reef community, making emphasis on species coexistence evidenced on trait evolution and environmental feedbacks. Forty-nine species represented in five families constituted the species pool from which a phylogenetic tree was reconstructed using mtDNA. We included data from 11 localities in the Western Caribbean (Colombia) including most reef types. To test diversity-environment and phenotype-environment relationships, phylogenetic community structure and trait evolution we carried out comparative analyses implementing ecological and evolutionary approaches. Phylogenetic inferences suggest clustering of oceanic reefs (e.g., atolls) contrasting with phylogenetic overdispersion of continental reefs (e.g., reefs banks). Additionally, atolls and barrier reefs had the highest species diversity (Shannon index) whereas phylogenetic diversity was higher in reef banks. The discriminant component analysis supported this differentiation between oceanic and continental reefs, where continental octocoral species tend to have greater calyx apertures, thicker branches, prominent calyces and azooxanthellate species. This analysis also indicated a clear separation between the slope and the remaining habitats, caused by the presence or absence of Symbiodinium. K statistic analysis showed that this trait is conserved as well as the branch shape. There was strong octocoral community structure with opposite diversity

  11. Octocoral Species Assembly and Coexistence in Caribbean Coral Reefs.

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    Johanna Velásquez

    Full Text Available What are the determinant factors of community assemblies in the most diverse ecosystem in the ocean? Coral reefs can be divided in continental (i.e., reefs that develop on the continental shelf, including siliciclastic reefs and oceanic (i.e., far off the continental shelf, usually on volcanic substratum; whether or not these habitat differences impose community-wide ecological divergence or species exclusion/coexistence with evolutionary consequences, is unknown.Studying Caribbean octocorals as model system, we determined the phylogenetic community structure in a coral reef community, making emphasis on species coexistence evidenced on trait evolution and environmental feedbacks. Forty-nine species represented in five families constituted the species pool from which a phylogenetic tree was reconstructed using mtDNA. We included data from 11 localities in the Western Caribbean (Colombia including most reef types. To test diversity-environment and phenotype-environment relationships, phylogenetic community structure and trait evolution we carried out comparative analyses implementing ecological and evolutionary approaches.Phylogenetic inferences suggest clustering of oceanic reefs (e.g., atolls contrasting with phylogenetic overdispersion of continental reefs (e.g., reefs banks. Additionally, atolls and barrier reefs had the highest species diversity (Shannon index whereas phylogenetic diversity was higher in reef banks. The discriminant component analysis supported this differentiation between oceanic and continental reefs, where continental octocoral species tend to have greater calyx apertures, thicker branches, prominent calyces and azooxanthellate species. This analysis also indicated a clear separation between the slope and the remaining habitats, caused by the presence or absence of Symbiodinium. K statistic analysis showed that this trait is conserved as well as the branch shape.There was strong octocoral community structure with opposite

  12. Chemical study and antifouling activity of Caribbean octocoral Eunicea laciniata

    International Nuclear Information System (INIS)

    Cuadrado Silva, Carmen Tatiana; Castellanos Hernandez, Leonardo; Osorno Reyes, Oscar Eduardo; Ramos Rodriguez, Freddy Alejandro; Duque Beltran, Carmenza

    2010-01-01

    The bioassay guided purification of the octocoral Eunicea laciniata organic extract, collected at Santa Marta bay, Colombia, allowed the isolation of the new compound (-)-3β-pregna-5,20-dienyl-β-D-arabinopyranoside (1), along with the known compounds 1(S * ),11(R * )-dolabell-3(E),7(E),12(18)-triene (2), 13-keto-1(S),11(R)-dolabell-3(E),7(E),12(18)-triene (3), cholest- 5,22-dien-3β-ol (4), cholesterol (5), y brassicasterol (6). The structure and absolute configuration of 1 was determined on based spectroscopic analyses (NMR and CD). The extract showed antifouling activity against five strains of marine bacteria associated to heavy fouled surfaces. Also showed activity against the cypris of the cosmopolitan barnacle Balanus amphitrite, and low toxicity in Artemia salina test. (author)

  13. Responses to high seawater temperatures in zooxanthellate octocorals.

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    Sammarco, Paul W; Strychar, Kevin B

    2013-01-01

    Increases in Sea Surface Temperatures (SSTs) as a result of global warming have caused reef-building scleractinian corals to bleach worldwide, a result of the loss of obligate endosymbiotic zooxanthellae. Since the 1980's, bleaching severity and frequency has increased, in some cases causing mass mortality of corals. Earlier experiments have demonstrated that zooxanthellae in scleractinian corals from three families from the Great Barrier Reef, Australia (Faviidae, Poritidae, and Acroporidae) are more sensitive to heat stress than their hosts, exhibiting differential symptoms of programmed cell death - apoptosis and necrosis. Most zooxanthellar phylotypes are dying during expulsion upon release from the host. The host corals appear to be adapted or exapted to the heat increases. We attempt to determine whether this adaptation/exaptation occurs in octocorals by examining the heat-sensitivities of zooxanthellae and their host octocoral alcyonacean soft corals - Sarcophyton ehrenbergi (Alcyoniidae), Sinularia lochmodes (Alcyoniidae), and Xenia elongata (Xeniidae), species from two different families. The soft coral holobionts were subjected to experimental seawater temperatures of 28, 30, 32, 34, and 36°C for 48 hrs. Host and zooxanthellar cells were examined for viability, apoptosis, and necrosis (in hospite and expelled) using transmission electron microscopy (TEM), fluorescent microscopy (FM), and flow cytometry (FC). As experimental temperatures increased, zooxanthellae generally exhibited apoptotic and necrotic symptoms at lower temperatures than host cells and were expelled. Responses varied species-specifically. Soft coral hosts were adapted/exapted to higher seawater temperatures than their zooxanthellae. As with the scleractinians, the zooxanthellae appear to be the limiting factor for survival of the holobiont in the groups tested, in this region. These limits have now been shown to operate in six species within five families and two orders of the Cnidaria

  14. Responses to high seawater temperatures in zooxanthellate octocorals.

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    Paul W Sammarco

    Full Text Available Increases in Sea Surface Temperatures (SSTs as a result of global warming have caused reef-building scleractinian corals to bleach worldwide, a result of the loss of obligate endosymbiotic zooxanthellae. Since the 1980's, bleaching severity and frequency has increased, in some cases causing mass mortality of corals. Earlier experiments have demonstrated that zooxanthellae in scleractinian corals from three families from the Great Barrier Reef, Australia (Faviidae, Poritidae, and Acroporidae are more sensitive to heat stress than their hosts, exhibiting differential symptoms of programmed cell death - apoptosis and necrosis. Most zooxanthellar phylotypes are dying during expulsion upon release from the host. The host corals appear to be adapted or exapted to the heat increases. We attempt to determine whether this adaptation/exaptation occurs in octocorals by examining the heat-sensitivities of zooxanthellae and their host octocoral alcyonacean soft corals - Sarcophyton ehrenbergi (Alcyoniidae, Sinularia lochmodes (Alcyoniidae, and Xenia elongata (Xeniidae, species from two different families. The soft coral holobionts were subjected to experimental seawater temperatures of 28, 30, 32, 34, and 36°C for 48 hrs. Host and zooxanthellar cells were examined for viability, apoptosis, and necrosis (in hospite and expelled using transmission electron microscopy (TEM, fluorescent microscopy (FM, and flow cytometry (FC. As experimental temperatures increased, zooxanthellae generally exhibited apoptotic and necrotic symptoms at lower temperatures than host cells and were expelled. Responses varied species-specifically. Soft coral hosts were adapted/exapted to higher seawater temperatures than their zooxanthellae. As with the scleractinians, the zooxanthellae appear to be the limiting factor for survival of the holobiont in the groups tested, in this region. These limits have now been shown to operate in six species within five families and two orders of

  15. Diversity of algal endosymbionts (zooxanthellae) in octocorals: the roles of geography and host relationships.

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    Van Oppen, M J H; Mieog, J C; Sánchez, C A; Fabricius, K E

    2005-07-01

    The presence, genetic identity and diversity of algal endosymbionts (Symbiodinium) in 114 species from 69 genera (20 families) of octocorals from the Great Barrier Reef (GBR), the far eastern Pacific (EP) and the Caribbean was examined, and patterns of the octocoral-algal symbiosis were compared with patterns in the host phylogeny. Genetic analyses of the zooxanthellae were based on ribosomal DNA internal transcribed spacer 1 (ITS1) region. In the GBR samples, Symbiodinium clades A and G were encountered with A and G being rare. Clade B zooxanthellae have been previously reported from a GBR octocoral, but are also rare in octocorals from this region. Symbiodinium G has so far only been found in Foraminifera, but is rare in these organisms. In the Caribbean samples, only Symbiodinium clades B and C are present. Hence, Symbiodinium diversity at the level of phylogenetic clades is lower in octocorals from the Caribbean compared to those from the GBR. However, an unprecedented level of ITS1 diversity was observed within individual colonies of some Caribbean gorgonians, implying either that these simultaneously harbour multiple strains of clade B zooxanthellae, or that ITS1 heterogeneity exists within the genomes of some zooxanthellae. Intracladal diversity based on ITS should therefore be interpreted with caution, especially in cases where no independent evidence exists to support distinctiveness, such as ecological distribution or physiological characteristics. All samples from EP are azooxanthellate. Three unrelated GBR taxa that are described in the literature as azooxanthellate (Junceella fragilis, Euplexaura nuttingi and Stereonephthya sp. 1) contain clade G zooxanthellae, and their symbiotic association with zooxanthellae was confirmed by histology. These corals are pale in colour, whereas related azooxanthellate species are brightly coloured. The evolutionary loss or gain of zooxanthellae may have altered the light sensitivity of the host tissues, requiring the

  16. Octocoral densities and mortalities in Gorgona Island, Colombia, Tropical Eastern Pacific

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    Juan A. Sánchez

    2014-02-01

    Full Text Available Owing to the decrease of reef organisms in general, it has become essential to study populations that are prone to marine diseases, with the purpose of developing accurate survivorship predictions and in turn alarm on triggers and drivers of disease outbreaks. In this study, we quantified the octocorals of Gorgona island, Tropical Eastern Pacific (Colombia, during 2007 and 2009 documenting a mass mortality occurred during 2008. We recorded 16 octocoral species with densities that ranged between 2 and 30 colonies m-2. Most abundant octocorals were Leptogorgia alba and Pacifigorgia spp. (Gorgoniidae: Octocorallia. During 2009 we noticed a mass mortality involving Pacifigorgia irene, P. adamsi, P. rubicunda and P. eximia, with a reduction of 70% of the colonies between 12 and 20 m in water depth. Around 5% of seafans during 2007 had an epizootic disease similar to aspergillosis, which seems the cause of the mass octocoral mortality. This disease outbreak observed in Gorgona island, and other nearby areas of the Colombian Pacific during 2007-2010, corresponded to extended periods of anomalous elevated seawater surface temperatures and thermal anomalies during the upwelling season of 2008. Constant monitoring of seawater temperatures and octocoral populations are urgently needed in this area to understand the nature of this new disease outbreak. Rev. Biol. Trop. 62 (Suppl. 1: 209-219. Epub 2014 February 01.

  17. Amphidinolide P from the Brazilian octocoral Stragulum bicolor

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    Thiciana S. Sousa

    Full Text Available Abstract Dinoflagellates are an important source of unique bioactive secondary metabolites. Symbiotic species, commonly named zooxanthellae, transfer most of their photosynthetically fixed carbon to their host. The mutualistic relationship provides the organic metabolites used for energy production but there are very few reports of the role of the dinoflagellates in the production of secondary metabolites in the symbiotic association. Corals and other related cnidarians are the most well-known animals containing symbiotic dinoflagellates. In the present paper we describe the isolation of amphidinolide P (1 from the octocoral Stragulum bicolor and its prey, the nudibranch Marionia limceana, collected off the coasts of Fortaleza (Ceará, Brazil. The coral extracts also contained 3-O-methyl derivative (2 of amphidinolide P, together with minor compounds still under investigation. Amphidinolides have been so far reported only in laboratory cultures of Amphidinium sp., thus compounds 1 and 2 represents the first identification of these polyketides in invertebrates. The finding proves the possibility to isolate amphidinolides from a natural symbiosis, enabling further biological and biotechnological studies.

  18. Energy budget for the cultured, zooxanthellate octocoral Sinularia flexibilis.

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    Khalesi, Mohammad K; Beeftink, H H; Wijffels, R H

    2011-12-01

    The zooxanthellate octocoral Sinularia flexibilis is a producer of potential pharmaceutically important metabolites such as antimicrobial and cytotoxic substances. Controlled rearing of the coral, as an alternative for commercial exploitation of these compounds, requires the study of species-specific growth requirements. In this study, phototrophic vs. heterotrophic daily energy demands of S. flexibilis was investigated through light and Artemia feeding trials in the laboratory. Rate of photosynthetic oxygen by zooxanthellae in light (≈200 μmol quanta m⁻² s⁻¹) was measured for the coral colonies with and without feeding on Artemia nauplii. Respiratory oxygen was measured in the dark, again with and without Artemia nauplii. Photosynthesis-irradiance curve at light intensities of 0, 50, 100, 200, and 400 μmol quanta m⁻² s⁻¹ showed an increase in photosynthetic oxygen production up to a light intensity between 100 and 200 μmol quanta m⁻² s⁻¹. The photosynthesis to respiration ratio (P/R > 1) confirmed phototrophy of S. flexibilis. Both fed and non-fed colonies in the light showed high carbon contribution by zooxanthellae to animal (host) respiration values of 111-127%. Carbon energy equivalents allocated to the coral growth averaged 6-12% of total photosynthesis energy (mg C g⁻¹ buoyant weight day⁻¹ and about 0.02% of the total daily radiant energy. "Light utilization efficiency (ε)" estimated an average ε value of 75% 12 h⁻¹ for coral practical energetics. This study shows that besides a fundamental role of phototrophy vs. heterotrophy in daily energy budget of S. flexibilis, an efficient fraction of irradiance is converted to useable energy.

  19. Partial quantification of pigments extracted from the zooxanthellate octocoral Sinularia flexibilis at varying irradiances

    NARCIS (Netherlands)

    Khalesi, M.K.; Lamers, P.P.

    2010-01-01

    Chlorophyll-a (chl-a) and carotenoid pigments of the zooxanthellate octocoral Sinularia flexibilis were analyzed using high performance liquid chromatography following exposure to three light intensities for over 30 days. From the coral fragments located at different light intensities, a total

  20. Cladielloides A and B: New Eunicellin-Type Diterpenoids from an Indonesian Octocoral Cladiella sp

    Science.gov (United States)

    Chen, Yung-Husan; Tai, Chia-Ying; Hwang, Tsong-Long; Weng, Ching-Feng; Li, Jan-Jung; Fang, Lee-Shing; Wang, Wei-Hsien; Wu, Yang-Chang; Sung, Ping-Jyun

    2010-01-01

    Two new eunicellin-type diterpenoids, cladielloides A (1) and B (2), which were found to possess a 2-hydroxybutyroxy group in their structures, were isolated from an Indonesian octocoral identified as Cladiella sp. The structures of eunicellins 1 and 2 were elucidated by spectroscopic methods. Cladielloide B (2) exhibited moderate cytotoxicity toward CCRF-CEM tumor cells and this compound displayed significant inhibitory effects on superoxide anion generation and elastase release by human neutrophils. PMID:21339957

  1. The masquerade game: marine mimicry adaptation between egg-cowries and octocorals

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    Juan A. Sánchez

    2016-08-01

    Full Text Available Background. Background matching, as a camouflage strategy, is one of the most outstanding examples of adaptation, where little error or mismatch means high vulnerability to predation. It is assumed that the interplay of natural selection and adaptation are the main evolutionary forces shaping the great diversity of phenotypes observed in mimicry; however, there may be other significant processes that intervene in the development of mimicry such as phenotypic plasticity. Based on observations of background mismatching during reproduction events of egg-cowries, sea snails of the family Ovulidae that mimic the octocoral where they inhabit, we wondered if they match the host species diversity. Using observations in the field and molecular systematics, we set out to establish whether the different egg-cowrie color/shape polymorphisms correspond to distinct lineages restricted to specific octocoral species. Methods. Collection and observations of egg-cowries and their octocoral hosts were done using SCUBA diving between 2009 and 2012 at two localities in the Tropical Eastern Pacific (TEP, Malpelo Island and Cabo Corrientes (Colombia. Detailed host preference observations were done bi-annually at Malpelo Island. We analyzed the DNA sequence of the mitochondrial genes COIand 16S rDNA, extensively used in phylogenetic and DNA barcoding studies, to assess the evolutionary relationship among different egg-cowrie colorations and morphologies. Results. No genetic divergence among egg-cowries associated to different species of the same octocoral genus was observed based on the two mitochondrial genes analyzed. For instance, all egg-cowrie individuals from the two sampled localities observed on 8 different Pacifigorgia-Eugorgia species showed negligible mitochondrial divergence yet large morphologic divergence, which suggests that morphologies belonging to at least two sea snail species, Simnia avena(=S. aequalis and Simnialena rufa, can cross

  2. Microbiomes of Muricea californica and M. fruticosa: Comparative Analyses of Two Co-occurring Eastern Pacific Octocorals.

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    Holm, Johanna B; Heidelberg, Karla B

    2016-01-01

    Octocorals are sources of novel but understudied microbial diversity. Conversely, scleractinian or reef-building coral microbiomes have been heavily examined in light of the threats of climate change. Muricea californica and Muricea fruticosa are two co-occurring species of gorgonian octocoral abundantly found in the kelp forests of southern California, and thus provide an excellent basis to determine if octocoral microbiomes are host specific. Using Illumina MiSeq amplicon sequencing and replicate samples, we evaluated the microbiomes collected from multiple colonies of both species of Muricea to measure both inter- and intra-colony microbiome variabilities. In addition, microbiomes from overlying sea water and nearby zoanthids (another benthic invertebrate) were also included in the analysis to evaluate whether bacterial taxa specifically associate with octocorals. This is also the first report of microbiomes from these species of Muricea. We show that microbiomes isolated from each sample type are distinct, and specifically, that octocoral species type had the greatest effect on predicting the composition of the Muricea microbiome. Bacterial taxa contributing to compositional differences include distinct strains of Mycoplasma associated with either M. californica or M. fruticosa, an abundance of Spirochaetes observed on M. californica, and a greater diversity of γ-Proteobacteria associated with M. fruticosa. Many of the bacterial taxa contributing to these differences are known for their presence in photosymbiont-containing invertebrate microbiomes.

  3. Octocorals in a changing environment: Seasonal response of stress biomarkers in natural populations of Veretillum cynomorium

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    Madeira, Carolina; Madeira, Diana; Vinagre, Catarina; Diniz, Mário

    2015-09-01

    Current concerns about climate change emphasize the need for an accurate monitoring of physiological conditions in wild populations. Therefore, the aims of this work were to a) assess the response of the octocoral Veretillum cynomorium to thermal variation in natural populations during low tide, by quantifying several biochemical indicators of thermal and oxidative stress and b) evaluate the effect of seasonality in the results and the adequacy of the use of biochemical indicators of stress in field monitoring studies in octocorals. Sampling took place during spring (April) and summer (June). Heat shock protein (Hsp70) and ubiquitin (Ub) content, enzyme activities - superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), and lipid peroxidation (LPO) were assessed in rachis and peduncle tissues separately. The results showed significant seasonal fluctuations in the set of biomarkers tested. Differences were detected between spring and summer, with significant decreases in biomarker levels from April to June being a major observed trend. These results suggest that V. cynomorium is thermo-tolerant during summer low tide conditions. Seasonal variation seems to reflect a metabolic suppression strategy and/or may also be related to seasonal changes in food availability and reproductive status. Differences in activity between tissue types were also found significant for GST, LPO and Ub. Biomarker levels were correlated with total protein concentration, but not with wet body weight of the specimens. This study suggests that season influences the expression of biomarkers and must be taken into consideration in the preliminary stages of sampling design for climate change biomonitoring studies. In addition, the results suggest that this octocoral species is likely to survive in future challenging thermal conditions.

  4. Uprolides N, O and P from the Panamanian Octocoral Eunicea succinea

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    Daniel Torres-Mendoza

    2016-06-01

    Full Text Available Three new diterpenes, uprolide N (1, uprolide O (2, uprolide P (3 and a known one, dolabellane (4, were isolated from the CH2Cl2-MeOH extract of the gorgonian octocoral Eunicea succinea, collected from Bocas del Toro, on the Caribbean coast of Panama. Their structures were determined using spectroscopic analyses, including 1D and 2D NMR and high-resolution mass spectrometry (HRMS together with molecular modeling studies. Compounds 1–3 displayed anti-inflammatory properties by inhibiting production of Tumor Necrosis Factor (TNF and Interleukin (IL-6 induced by lipopolysaccharide (LPS in murine macrophages.

  5. A taxonomic survey of Saudi Arabian Red Sea octocorals (Cnidaria: Alcyonacea)

    KAUST Repository

    Haverkort-Yeh, Roxanne D.

    2013-05-04

    A preliminary survey of Saudi Arabian Alcyonacea is presented, which combines classical taxonomy, multilocus molecular barcodes, and in situ photographs. We explored 14 locations along the west coast of the Kingdom of Saudi Arabia to assess the regional taxonomic diversity of non-gorgonian alcyonaceans. We collected samples from a total of 74 colonies, distributed among four families: 18 colonies of Alcyoniidae, 14 of Nephtheidae, 9 of Tubiporidae, and 33 of Xeniidae. We sequenced the octocorals using multiple nuclear [ribosomal Internal Transcribed Spacers (ITS) and ATP Synthetase Subunit α (ATPSα)] and mitochondrial [MutS homolog (mtMutS) and Cytochrome C Oxidase subunit one (COI)] loci, providing molecular barcodes which will: (1) allow direct comparison of biodiversity from this location to others for which molecular data are available, and (2) facilitate future identifications of these taxa. Finally, this preliminary phylogeny of sampled taxa provides insights on the resolution of mitochondrial versus nuclear loci, and highlights octocoral taxa that require further taxonomic attention. © 2013 Senckenberg Gesellschaft für Naturforschung and Springer-Verlag Berlin Heidelberg.

  6. Briarenols C–E, New Polyoxygenated Briaranes from the Octocoral Briareum excavatum

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    Nan-Fu Chen

    2017-03-01

    Full Text Available Three new polyoxygenated briarane diterpenoids, briarenols C–E (1–3, were isolated from the octocoral Briareum excavatum. The structures of briaranes 1–3 were elucidated by interpretation of spectroscopic data, and the methylenecyclohexane ring in 1 was found to exist in a twisted boat conformation. Briarenol D (2 displayed an inhibitory effect on the release of elastase by human neutrophils with an IC50 value of 4.65 μM. Briarenol E (3 was found to inhibit the protein expression of pro-inflammatory inducible nitric oxide synthase (iNOS in a murine macrophage-like cell line, RAW 264.7, stimulated with lipopolysaccharides (LPS.

  7. Molecular and Morphological Species Boundaries in the Gorgonian Octocoral Genus Pterogorgia (Octocorallia: Gorgoniidae.

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    Herman H Wirshing

    Full Text Available Most gorgonian octocoral species are described using diagnostic characteristics of their sclerites (microscopic skeletal components. Species in the genus Pterogorgia, however, are separated primarily by differences in their calyx and branch morphology. Specimens of a morphologically unusual Pterogorgia collected from Saba Bank in the NE Caribbean Sea were found with calyx morphology similar to P. citrina and branch morphology similar to P. guadalupensis. In order to test morphological species boundaries, and the validity of calyx and branch morphology as systematic characters, a phylogenetic analysis was undertaken utilizing partial gene fragments of three mitochondrial (mtMutS, cytochrome b, and igr4; 726bp total and two nuclear (ITS2, 166bp; and SRP54 intron, 143bp loci. The datasets for nuclear and mitochondrial loci contained few phylogenetically informative sites, and tree topologies did not resolve any of the morphological species as monophyletic groups. Instead, the mitochondrial loci and SRP54 each recovered two clades but were slightly incongruent, with a few individuals of P. guadalupensis represented in both clades with SRP54. A concatenated dataset of these loci grouped all P. anceps and P. guadalupensis in a clade, and P. citrina and the Pterogorgia sp. from Saba Bank in a sister clade, but with minimal variation/resolution within each clade. However, in common with other octocoral taxa, the limited genetic variation may not have been able to resolve whether branch variation represents intraspecific variation or separate species. Therefore, these results suggest that there are at least two phylogenetic lineages of Pterogorgia at the species level, and the atypical Pterogorgia sp. may represent an unusual morphotype of P. citrina, possibly endemic to Saba Bank. Branch morphology does not appear to be a reliable morphological character to differentiate Pterogorgia species (e.g., branches "flat" or "3-4 edges" in P. guadalupensis and P

  8. Complete mitochondrial genomes elucidate phylogenetic relationships of the deep-sea octocoral families Coralliidae and Paragorgiidae

    Science.gov (United States)

    Figueroa, Diego F.; Baco, Amy R.

    2014-01-01

    In the past decade, molecular phylogenetic analyses of octocorals have shown that the current morphological taxonomic classification of these organisms needs to be revised. The latest phylogenetic analyses show that most octocorals can be divided into three main clades. One of these clades contains the families Coralliidae and Paragorgiidae. These families share several taxonomically important characters and it has been suggested that they may not be monophyletic; with the possibility of the Coralliidae being a derived branch of the Paragorgiidae. Uncertainty exists not only in the relationship of these two families, but also in the classification of the two genera that make up the Coralliidae, Corallium and Paracorallium. Molecular analyses suggest that the genus Corallium is paraphyletic, and it can be divided into two main clades, with the Paracorallium as members of one of these clades. In this study we sequenced the whole mitochondrial genome of five species of Paragorgia and of five species of Corallium to use in a phylogenetic analysis to achieve two main objectives; the first to elucidate the phylogenetic relationship between the Paragorgiidae and Coralliidae and the second to determine whether the genera Corallium and Paracorallium are monophyletic. Our results show that other members of the Coralliidae share the two novel mitochondrial gene arrangements found in a previous study in Corallium konojoi and Paracorallium japonicum; and that the Corallium konojoi arrangement is also found in the Paragorgiidae. Our phylogenetic reconstruction based on all the protein coding genes and ribosomal RNAs of the mitochondrial genome suggest that the Coralliidae are not a derived branch of the Paragorgiidae, but rather a monophyletic sister branch to the Paragorgiidae. While our manuscript was in review a study was published using morphological data and several fragments from mitochondrial genes to redefine the taxonomy of the Coralliidae. Paracorallium was subsumed

  9. Search for mesophotic octocorals (Cnidaria, Anthozoa and their phylogeny: I. A new sclerite-free genus from Eilat, northern Red Sea

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    Yehuda Benayahu

    2017-06-01

    Full Text Available This communication describes a new octocoral, Altumia delicata gen. n. & sp. n. (Octocorallia: Clavulariidae, from mesophotic reefs of Eilat (northern Gulf of Aqaba, Red Sea. This species lives on dead antipatharian colonies and on artificial substrates. It has been recorded from deeper than 60 m down to 140 m and is thus considered to be a lower mesophotic octocoral. It has no sclerites and features no symbiotic zooxanthellae. The new genus is compared to other known sclerite-free octocorals. Molecular phylogenetic analyses place it in a clade with members of families Clavulariidae and Acanthoaxiidae, and for now we assign it to the former, based on colony morphology. The polyphyletic family Clavulariidae is, however, in need of a thorough revision once the morphological distinctions among its phylogenetically distinct clades are better understood.

  10. Circulation of fluids in the gastrovascular system of a stoloniferan octocoral.

    Science.gov (United States)

    Parrin, Austin P; Netherton, Sarah E; Bross, Lori S; McFadden, Catherine S; Blackstone, Neil W

    2010-10-01

    Cilia-based transport systems characterize sponges and placozoans. Cilia are employed in cnidarian gastrovascular systems as well, but typically function in concert with muscular contractions. Previous reports suggest that anthozoans may be an exception to this pattern, utilizing only cilia in their gastrovascular systems. With an inverted microscope and digital image analysis, we used stoloniferan octocoral colonies growing on microscope cover glass to quantitatively describe the movement of fluids in this system for the first time. Flow in stolons (diameter ≈300 μm) is simultaneously bidirectional, with average velocities of 100-200 μm/s in each direction. Velocities are maximal immediately adjacent to the stolon wall and decrease to a minimum in the center of the stolon. Flow velocity is unaffected by stolonal contractions, suggesting that muscular peristalsis is not a factor in propelling the flow. Stolon intersections (diameter ≈500 μm) occur below polyps and serve as traffic roundabouts with unidirectional, circular flow. Such cilia-driven transport may be the plesiomorphic state for the gastrovascular system of cnidarians.

  11. Bacterial community diversity of the deep-sea octocoral Paramuricea placomus

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    Christina A. Kellogg

    2016-09-01

    Full Text Available Compared to tropical corals, much less is known about deep-sea coral biology and ecology. Although the microbial communities of some deep-sea corals have been described, this is the first study to characterize the bacterial community associated with the deep-sea octocoral, Paramuricea placomus. Samples from five colonies of P. placomus were collected from Baltimore Canyon (379–382 m depth in the Atlantic Ocean off the east coast of the United States of America. DNA was extracted from the coral samples and 16S rRNA gene amplicons were pyrosequenced using V4-V5 primers. Three samples sequenced deeply (>4,000 sequences each and were further analyzed. The dominant microbial phylum was Proteobacteria, but other major phyla included Firmicutes and Planctomycetes. A conserved community of bacterial taxa held in common across the three P. placomus colonies was identified, comprising 68–90% of the total bacterial community depending on the coral individual. The bacterial community of P. placomus does not appear to include the genus Endozoicomonas, which has been found previously to be the dominant bacterial associate in several temperate and tropical gorgonians. Inferred functionality suggests the possibility of nitrogen cycling by the core bacterial community.

  12. Productivity links morphology, symbiont specificity and bleaching in the evolution of Caribbean octocoral symbioses.

    Science.gov (United States)

    Baker, David M; Freeman, Christopher J; Knowlton, Nancy; Thacker, Robert W; Kim, Kiho; Fogel, Marilyn L

    2015-12-01

    Many cnidarians host endosymbiotic dinoflagellates from the genus Symbiodinium. It is generally assumed that the symbiosis is mutualistic, where the host benefits from symbiont photosynthesis while providing protection and photosynthetic substrates. Diverse assemblages of symbiotic gorgonian octocorals can be found in hard bottom communities throughout the Caribbean. While current research has focused on the phylo- and population genetics of gorgonian symbiont types and their photo-physiology, relatively less work has focused on biogeochemical benefits conferred to the host and how these benefits vary across host species. Here we examine this symbiosis among 11 gorgonian species collected in Bocas del Toro, Panama. By coupling light and dark bottle incubations (P/R) with (13)C-bicarbonate tracers, we quantified the link between holobiont oxygen metabolism with carbon assimilation and translocation from symbiont to host. Our data show that P/R varied among species, and was correlated with colony morphology and polyp size. Sea fans and sea plumes were net autotrophs (P/R>1.5), while nine species of sea rods were net heterotrophs with most below compensation (P/R<1.0). (13)C assimilation corroborated the P/R results, and maximum δ(13)Chost values were strongly correlated with polyp size, indicating higher productivity by colonies with high polyp SA:V. A survey of gorgonian-Symbiodinium associations revealed that productive species maintain specialized, obligate symbioses and are more resistant to coral bleaching, whereas generalist and facultative associations are common among sea rods that have higher bleaching sensitivities. Overall, productivity and polyp size had strong phylogenetic signals with carbon fixation and polyp size showing evidence of trait covariance.

  13. Histology and ultrastructure of the coenenchyme of the octocoral Swiftia exserta, a model organism for innate immunity/graft rejection.

    Science.gov (United States)

    Menzel, L P; Tondo, C; Stein, B; Bigger, C H

    2015-04-01

    The octocoral Swiftia exserta has been utilized extensively in our laboratory to study innate immune reactions in Cnidaria such as wound healing, auto- and allo-graft reactions, and for some classical "foreign body" phagocytosis experiments. All of these reactions occur in the coenenchyme of the animal, the colonial tissue surrounding the axial skeleton in which the polyps are embedded, and do not rely on nematocysts or directly involve the polyps. In order to better understand some of the cellular reactions occurring in the coenenchyme, the present study employed several cytochemical methods (periodic acid-Schiff reaction, Mallory's aniline blue collagen stain, and Gomori's trichrome stain) and correlated the observed structures with electron microscopy (both scanning and transmission). Eight types of cells were apparent in the coenenchyme of S. exserta, exclusive of gastrodermal tissue: (i) epithelial ectoderm cells, (ii) oblong granular cells, (iii) granular amoebocytes, (iv) morula-like cells, (v) mesogleal cells, (vi) sclerocytes, (vii) axial epithelial cells, and (viii) cnidocytes with mostly atrichous isorhiza nematocysts. Several novel organizational features are now apparent from transmission electron micrographs: the ectoderm consists of a single layer of flat epithelial cells, the cell types of the mesoglea extend from beneath the thin ectoderm throughout the mesogleal cell cords, the organization of the solenia gastroderm consists of a single layer of cells, and two nematocyst types have been found. A new interpretation of the cellular architecture of S. exserta, and more broadly, octocoral biology is now possible. Copyright © 2014 Elsevier GmbH. All rights reserved.

  14. Molecular and morphological systematics of the Ellisellidae (Coelenterata: Octocorallia): Parallel evolution in a globally distributed family of octocorals

    KAUST Repository

    Bilewitch, Jaret P.

    2014-04-01

    The octocorals of the Ellisellidae constitute a diverse and widely distributed family with subdivisions into genera based on colonial growth forms. Branching patterns are repeated in several genera and congeners often display region-specific variations in a given growth form. We examined the systematic patterns of ellisellid genera and the evolution of branching form diversity using molecular phylogenetic and ancestral morphological reconstructions. Six of eight included genera were found to be polyphyletic due to biogeographical incompatibility with current taxonomic assignments and the creation of at least six new genera plus several reassignments among existing genera is necessary. Phylogenetic patterns of diversification of colony branching morphology displayed a similar transformation order in each of the two primary ellisellid clades, with a sea fan form estimated as the most-probable common ancestor with likely origins in the Indo-Pacific region. The observed parallelism in evolution indicates the existence of a constraint on the genetic elements determining ellisellid colonial morphology. However, the lack of correspondence between levels of genetic divergence and morphological diversity among genera suggests that future octocoral studies should focus on the role of changes in gene regulation in the evolution of branching patterns. © 2014 Elsevier Inc.

  15. Molecular and morphological systematics of the Ellisellidae (Coelenterata: Octocorallia): Parallel evolution in a globally distributed family of octocorals

    KAUST Repository

    Bilewitch, Jaret P.; Ekins, Merrick; Hooper, John; Degnan, Sandie M.

    2014-01-01

    The octocorals of the Ellisellidae constitute a diverse and widely distributed family with subdivisions into genera based on colonial growth forms. Branching patterns are repeated in several genera and congeners often display region-specific variations in a given growth form. We examined the systematic patterns of ellisellid genera and the evolution of branching form diversity using molecular phylogenetic and ancestral morphological reconstructions. Six of eight included genera were found to be polyphyletic due to biogeographical incompatibility with current taxonomic assignments and the creation of at least six new genera plus several reassignments among existing genera is necessary. Phylogenetic patterns of diversification of colony branching morphology displayed a similar transformation order in each of the two primary ellisellid clades, with a sea fan form estimated as the most-probable common ancestor with likely origins in the Indo-Pacific region. The observed parallelism in evolution indicates the existence of a constraint on the genetic elements determining ellisellid colonial morphology. However, the lack of correspondence between levels of genetic divergence and morphological diversity among genera suggests that future octocoral studies should focus on the role of changes in gene regulation in the evolution of branching patterns. © 2014 Elsevier Inc.

  16. Application of DNA barcoding in biodiversity studies of shallow-water octocorals: molecular proxies agree with morphological estimates of species richness in Palau

    Science.gov (United States)

    McFadden, C. S.; Brown, A. S.; Brayton, C.; Hunt, C. B.; van Ofwegen, L. P.

    2014-06-01

    The application of DNA barcoding to anthozoan cnidarians has been hindered by their slow rates of mitochondrial gene evolution and the failure to identify alternative molecular markers that distinguish species reliably. Among octocorals, however, multilocus barcodes can distinguish up to 70 % of morphospecies, thereby facilitating the identification of species that are ecologically important but still very poorly known taxonomically. We tested the ability of these imperfect DNA barcodes to estimate species richness in a biodiversity survey of the shallow-water octocoral fauna of Palau using multilocus ( COI, mtMutS, 28S rDNA) sequences obtained from 305 specimens representing 38 genera of octocorals. Numbers and identities of species were estimated independently (1) by a taxonomic expert using morphological criteria and (2) by assigning sequences to molecular operational taxonomic units (MOTUs) using predefined genetic distance thresholds. Estimated numbers of MOTUs ranged from 73 to 128 depending on the barcode and distance threshold applied, bracketing the estimated number of 118 morphospecies. Concordance between morphospecies identifications and MOTUs ranged from 71 to 75 % and differed little among barcodes. For the speciose and ecologically dominant genus Sinularia, however, we were able to identify 95 % of specimens correctly simply by comparing mtMutS sequences and in situ photographs of colonies to an existing vouchered database. Because we lack a clear understanding of species boundaries in most of these taxa, numbers of morphospecies and MOTUs are both estimates of the true species diversity, and we cannot currently determine which is more accurate. Our results suggest, however, that the two methods provide comparable estimates of species richness for shallow-water Indo-Pacific octocorals. Use of molecular barcodes in biodiversity surveys will facilitate comparisons of species richness and composition among localities and over time, data that do not

  17. Toxicity of oil and dispersant on the deep water gorgonian octocoral Swiftia exserta, with implications for the effects of the Deepwater Horizon oil spill.

    Science.gov (United States)

    Frometa, Janessy; DeLorenzo, Marie E; Pisarski, Emily C; Etnoyer, Peter J

    2017-09-15

    Benthic surveys of mesophotic reefs in the Gulf of Mexico post Deepwater Horizon (DWH) showed that Swiftia exserta octocorals exhibited significantly more injury than in years before the spill. To determine the vulnerability of S. exserta to oil and dispersants, 96h toxicity assays of surrogate DWH oil water-accommodated fractions (WAF), Corexit® 9500 dispersant, and the combination of both (CEWAF) were conducted in the laboratory. Fragment mortality occurred within 48h for some fragments in the dispersant-alone and oil-dispersant treatments, while the WAF group remained relatively unaffected. The 96h LC 50 values were 70.27mg/L for Corexit-alone and 41.04mg/L for Corexit in CEWAF. This study provides new information on octocoral sensitivity to toxins, and indicates that combinations of oil and dispersants are more toxic to octocorals than exposure to oil alone. These results have important implications for the assessment of effects of the DWH spill on deep-water organisms. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Environmental influences on the Indo-Pacific octocoral Isis hippuris Linnaeus 1758 (Alcyonacea: Isididae): genetic fixation or phenotypic plasticity?

    Science.gov (United States)

    Rowley, Sonia J; Pochon, Xavier; Watling, Les

    2015-01-01

    As conspicuous modular components of benthic marine habitats, gorgonian (sea fan) octocorals have perplexed taxonomists for centuries through their shear diversity, particularly throughout the Indo-Pacific. Phenotypic incongruence within and between seemingly unitary lineages across contrasting environments can provide the raw material to investigate processes of disruptive selection. Two distinct phenotypes of the Isidid Isis hippurisLinnaeus, 1758 partition between differing reef environments: long-branched bushy colonies on degraded reefs, and short-branched multi/planar colonies on healthy reefs within the Wakatobi Marine National Park (WMNP), Indonesia. Multivariate analyses reveal phenotypic traits between morphotypes were likely integrated primarily at the colony level with increased polyp density and consistently smaller sclerite dimensions at the degraded site. Sediment load and turbidity, hence light availability, primarily influenced phenotypic differences between the two sites. This distinct morphological dissimilarity between the two sites is a reliable indicator of reef health; selection primarily acting on colony morphology, porosity through branching structure, as well as sclerite diversity and size. ITS2 sequence and predicted RNA secondary structure further revealed intraspecific variation between I. hippuris morphotypes relative to such environments (ΦST = 0.7683, P < 0.001). This evidence suggests-but does not confirm-that I. hippuris morphotypes within the WMNP are two separate species; however, to what extent and taxonomic assignment requires further investigation across its full geographic distribution. Incongruence between colonies present in the WMNP with tenuously described Isis alternatives (Isis reticulataNutting, 1910, Isis minorbrachyblastaZou, Huang & Wang, 1991), questions the validity of such assignments. Furthermore, phylogenetic analyses confirm early taxonomic suggestion that the characteristic jointed axis of the Isididae is in

  19. Environmental influences on the Indo–Pacific octocoral Isis hippuris Linnaeus 1758 (Alcyonacea: Isididae): genetic fixation or phenotypic plasticity?

    Science.gov (United States)

    Pochon, Xavier; Watling, Les

    2015-01-01

    As conspicuous modular components of benthic marine habitats, gorgonian (sea fan) octocorals have perplexed taxonomists for centuries through their shear diversity, particularly throughout the Indo–Pacific. Phenotypic incongruence within and between seemingly unitary lineages across contrasting environments can provide the raw material to investigate processes of disruptive selection. Two distinct phenotypes of the Isidid Isis hippuris Linnaeus, 1758 partition between differing reef environments: long-branched bushy colonies on degraded reefs, and short-branched multi/planar colonies on healthy reefs within the Wakatobi Marine National Park (WMNP), Indonesia. Multivariate analyses reveal phenotypic traits between morphotypes were likely integrated primarily at the colony level with increased polyp density and consistently smaller sclerite dimensions at the degraded site. Sediment load and turbidity, hence light availability, primarily influenced phenotypic differences between the two sites. This distinct morphological dissimilarity between the two sites is a reliable indicator of reef health; selection primarily acting on colony morphology, porosity through branching structure, as well as sclerite diversity and size. ITS2 sequence and predicted RNA secondary structure further revealed intraspecific variation between I. hippuris morphotypes relative to such environments (ΦST = 0.7683, P < 0.001). This evidence suggests—but does not confirm—that I. hippuris morphotypes within the WMNP are two separate species; however, to what extent and taxonomic assignment requires further investigation across its full geographic distribution. Incongruence between colonies present in the WMNP with tenuously described Isis alternatives (Isis reticulata Nutting, 1910, Isis minorbrachyblasta Zou, Huang & Wang, 1991), questions the validity of such assignments. Furthermore, phylogenetic analyses confirm early taxonomic suggestion that the characteristic jointed axis of the

  20. Environmental influences on the Indo–Pacific octocoral Isis hippuris Linnaeus 1758 (Alcyonacea: Isididae: genetic fixation or phenotypic plasticity?

    Directory of Open Access Journals (Sweden)

    Sonia J. Rowley

    2015-08-01

    Full Text Available As conspicuous modular components of benthic marine habitats, gorgonian (sea fan octocorals have perplexed taxonomists for centuries through their shear diversity, particularly throughout the Indo–Pacific. Phenotypic incongruence within and between seemingly unitary lineages across contrasting environments can provide the raw material to investigate processes of disruptive selection. Two distinct phenotypes of the Isidid Isis hippuris Linnaeus, 1758 partition between differing reef environments: long-branched bushy colonies on degraded reefs, and short-branched multi/planar colonies on healthy reefs within the Wakatobi Marine National Park (WMNP, Indonesia. Multivariate analyses reveal phenotypic traits between morphotypes were likely integrated primarily at the colony level with increased polyp density and consistently smaller sclerite dimensions at the degraded site. Sediment load and turbidity, hence light availability, primarily influenced phenotypic differences between the two sites. This distinct morphological dissimilarity between the two sites is a reliable indicator of reef health; selection primarily acting on colony morphology, porosity through branching structure, as well as sclerite diversity and size. ITS2 sequence and predicted RNA secondary structure further revealed intraspecific variation between I. hippuris morphotypes relative to such environments (ΦST = 0.7683, P < 0.001. This evidence suggests—but does not confirm—that I. hippuris morphotypes within the WMNP are two separate species; however, to what extent and taxonomic assignment requires further investigation across its full geographic distribution. Incongruence between colonies present in the WMNP with tenuously described Isis alternatives (Isis reticulata Nutting, 1910, Isis minorbrachyblasta Zou, Huang & Wang, 1991, questions the validity of such assignments. Furthermore, phylogenetic analyses confirm early taxonomic suggestion that the characteristic jointed

  1. Pseudopterosin Biosynthesis: Aromatization of the Diterpene Cyclase Product, Elisabethatriene

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    Amber C. Kohl

    2003-11-01

    Full Text Available Abstract: Putative precursors in pseudopterosin biosynthesis, the hydrocarbons isoelisabethatriene (10 and erogorgiaene (11, have been identified from an extract of Pseudopterogorgia elisabethae collected in the Florida Keys. Biosynthetic experiments designed to test the utilization of these compounds in pseudopterosin production revealed that erogorgiaene is transformed to pseudopterosins A-D. Together with our previous data, it is now apparent that early steps in pseudopterosin biosynthesis involve the cyclization of geranylgeranyl diphosphate to elisabethatriene followed by the dehydrogenation and aromatization to erogorgiaene.

  2. Large-Scale Genotyping-by-Sequencing Indicates High Levels of Gene Flow in the Deep-Sea Octocoral Swiftia simplex (Nutting 1909 on the West Coast of the United States.

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    Meredith V Everett

    Full Text Available Deep-sea corals are a critical component of habitat in the deep-sea, existing as regional hotspots for biodiversity, and are associated with increased assemblages of fish, including commercially important species. Because sampling these species is so difficult, little is known about the connectivity and life history of deep-sea octocoral populations. This study evaluates the genetic connectivity among 23 individuals of the deep-sea octocoral Swiftia simplex collected from Eastern Pacific waters along the west coast of the United States. We utilized high-throughput restriction-site associated DNA (RAD-tag sequencing to develop the first molecular genetic resource for the deep-sea octocoral, Swiftia simplex. Using this technique we discovered thousands of putative genome-wide SNPs in this species, and after quality control, successfully genotyped 1,145 SNPs across individuals sampled from California to Washington. These SNPs were used to assess putative population structure across the region. A STRUCTURE analysis as well as a principal coordinates analysis both failed to detect any population differentiation across all geographic areas in these collections. Additionally, after assigning individuals to putative population groups geographically, no significant FST values could be detected (FST for the full data set 0.0056, and no significant isolation by distance could be detected (p = 0.999. Taken together, these results indicate a high degree of connectivity and potential panmixia in S. simplex along this portion of the continental shelf.

  3. Isolation and biological activities of secondary metabolites from the sponges monanchora aff. arbuscula, aplysina sp. petromica ciocalyptoides and topsentia ophiraphidies, from the ascidian didemnum ligulum and from the octocoral carijoa riisei; Isolamento e atividades biologicas de produtos naturais das esponjas monanchora arbuscula, aplysina sp., petromica ciocalyptoides e topsentia ophiraphidites, da ascidia didemnum ligulum e do octocoral carijoa riisei

    Energy Technology Data Exchange (ETDEWEB)

    Kossuga, Miriam H.; Lira, Simone P. de; Nascimento, Andrea M.; Gambardella, Maria Teresa P.; Berlinck, Roberto G.S. [Universidade de Sao Paulo (USP), Sao Carlos, SP (Brazil). Inst. de Quimica]. E-mail: rgsberlinck@iqsc.usp.br; Torres, Yohandra R. [Universidade Estadual do Centro-Oeste, Guarapuava, PR (Brazil). Dept. de Quimica; Nascimento, Gislene G.F. [Universidade Metodista de Piracicaba (UNIMEP), SP (Brazil). Faculdade de Ciencias da Saude; Pimenta, Eli F.; Silva, Marcio; Thiemann, Otavio H.; Oliva, Glaucius [Universidade de Sao Paulo (USP), Sao Carlos, SP (Brazil). Inst. de Fisica; Tempone, Andre G.; Melhem, Marcia S.C. [Instituto Adolfo Lutz, Sao Paulo, SP (Brazil). Div. de Biologia Medica; Souza, Ana O. de; Galetti, Fabio C.S.; Silva, Celio L. [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Medicina. Dept. de Bioquimica e Imunologia; Cavalcanti, Bruno; Pessoa, Claudia O.; Moraes, Manoel O. [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Faculdade de Medicina. Dept. de Fisiologia e Farmacologia; Hajdu, Eduardo [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Museu Nacional; Peixinho, Solange [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil). Dept. de Biologia; Rocha, Rosana M. [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Setor de Ciencias Biologicas. Dept. de Zoologia

    2007-09-15

    The investigation of extracts from six species of marine invertebrates yielded one new and several known natural products. Isoptilocaulin from the sponge Monanchora aff. arbuscula displayed antimicrobial activity at 1.3 mg/mL against an oxacillin-resistant strain of Staphylococcus aureus. Five inactive known dibromotyrosine derivatives, 2 6, were isolated from a new species of marine sponge, Aplysina sp. The sponges Petromica ciocalyptoides and Topsentia ophiraphidites yielded the known halistanol sulfate A (7) as an inhibitor of the antileishmanial target adenosine phosphoribosyl transferase. The ascidian Didemnum ligulum yielded asterubin (10) and the new N,N-dimethyl-O-methylethanolamine (11). The octocoral Carijoa riisei yielded the known 18-acetoxypregna-1,4,20-trien-3-one (12), which displayed cytotoxic activity against the cancer cell lines SF295, MDA-MB435, HCT8 and HL60. (author)

  4. Species distribution models of two critically endangered deep-sea octocorals reveal fishing impacts on vulnerable marine ecosystems in central Mediterranean Sea.

    Science.gov (United States)

    Lauria, V; Garofalo, G; Fiorentino, F; Massi, D; Milisenda, G; Piraino, S; Russo, T; Gristina, M

    2017-08-14

    Deep-sea coral assemblages are key components of marine ecosystems that generate habitats for fish and invertebrate communities and act as marine biodiversity hot spots. Because of their life history traits, deep-sea corals are highly vulnerable to human impacts such as fishing. They are an indicator of vulnerable marine ecosystems (VMEs), therefore their conservation is essential to preserve marine biodiversity. In the Mediterranean Sea deep-sea coral habitats are associated with commercially important crustaceans, consequently their abundance has dramatically declined due to the effects of trawling. Marine spatial planning is required to ensure that the conservation of these habitats is achieved. Species distribution models were used to investigate the distribution of two critically endangered octocorals (Funiculina quadrangularis and Isidella elongata) in the central Mediterranean as a function of environmental and fisheries variables. Results show that both species exhibit species-specific habitat preferences and spatial patterns in response to environmental variables, but the impact of trawling on their distribution differed. In particular F. quadrangularis can overlap with fishing activities, whereas I. elongata occurs exclusively where fishing is low or absent. This study represents the first attempt to identify key areas for the protection of soft and compact mud VMEs in the central Mediterranean Sea.

  5. Natural heterotrophic feeding by a temperate octocoral with symbiotic zooxanthellae: a contribution to understanding the mechanisms of die-off events

    Science.gov (United States)

    Coma, Rafel; Llorente-Llurba, Eduard; Serrano, Eduard; Gili, Josep-Maria; Ribes, Marta

    2015-06-01

    Octocorals are among the most emblematic and representative organisms of sublittoral communities in both tropical and temperate seas. Eunicella singularis is the most abundant gorgonian in shallow waters and the only gorgonian with symbiotic zooxanthellae in the Mediterranean Sea. We studied the natural diet and prey capture rate of this species over an annual cycle and characterized prey digestion time over the natural temperature regime. The species captured zooplankton prey between 40 and 920 µm. A mean content of 0.14 ± 0.02 prey polyp-1 was observed throughout the year. The strong pattern of decrease in digestion time with temperature increase (from 25 h at 13 °C to 8 h at 21 °C) allowed us to estimate that the prey capture rate was 0.017 ± 0.002 prey polyp-1 h-1 (mean ± SE); the ingestion rate exhibited a seasonal pattern with higher values in spring (0.007 µg C polyp-1 h-1). Feeding on zooplankton had a low contribution to the respiratory expenses of E. singularis except in early spring. Then, heterotrophic nutrition in the natural environment seems unable to meet basal metabolic requirements, especially in summer and fall. This result, in conjunction with the documented collapse of photosynthetic capacity above a warm temperature threshold, indicates the occurrence of a resource acquisition limitation that may play a role in the repeated summer die-off events of the species.

  6. Isolation and biological activities of secondary metabolites from the sponges monanchora aff. arbuscula, aplysina sp. petromica ciocalyptoides and topsentia ophiraphidies, from the ascidian didemnum ligulum and from the octocoral carijoa riisei

    International Nuclear Information System (INIS)

    Kossuga, Miriam H.; Lira, Simone P. de; Nascimento, Andrea M.; Gambardella, Maria Teresa P.; Berlinck, Roberto G.S.; Torres, Yohandra R.; Nascimento, Gislene G.F.; Pimenta, Eli F.; Silva, Marcio; Thiemann, Otavio H.; Oliva, Glaucius; Tempone, Andre G.; Melhem, Marcia S.C.; Souza, Ana O. de; Galetti, Fabio C.S.; Silva, Celio L.; Cavalcanti, Bruno; Pessoa, Claudia O.; Moraes, Manoel O.; Hajdu, Eduardo; Peixinho, Solange; Rocha, Rosana M.

    2007-01-01

    The investigation of extracts from six species of marine invertebrates yielded one new and several known natural products. Isoptilocaulin from the sponge Monanchora aff. arbuscula displayed antimicrobial activity at 1.3 mg/mL against an oxacillin-resistant strain of Staphylococcus aureus. Five inactive known dibromotyrosine derivatives, 2 6, were isolated from a new species of marine sponge, Aplysina sp. The sponges Petromica ciocalyptoides and Topsentia ophiraphidites yielded the known halistanol sulfate A (7) as an inhibitor of the antileishmanial target adenosine phosphoribosyl transferase. The ascidian Didemnum ligulum yielded asterubin (10) and the new N,N-dimethyl-O-methylethanolamine (11). The octocoral Carijoa riisei yielded the known 18-acetoxypregna-1,4,20-trien-3-one (12), which displayed cytotoxic activity against the cancer cell lines SF295, MDA-MB435, HCT8 and HL60. (author)

  7. IDENTIFICACIÓN DE ALGUNOS METABOLITOS SECUNDARIOS DEL EXTRACTO EN ACETATO DE ETILO DE Muricea sp.I IDENTIFICATION OF SOME SECONDARY METABOLITES FROM THE ETHYL- ACETATE-EXTRACT OF THE OCTOCORAL, Muricea sp.

    Directory of Open Access Journals (Sweden)

    Ángel Camacho

    2018-04-01

    Full Text Available Some chromatographic fractions obtained from the ethyl-acetate-extract of the unidentified octocoral species of the genus, Muricea , showed antibacterial activity against Escherichia coli , Salmonella enteritidis , Citrobacter freundii , Staphylococcus aureus , and Bacillus subtlis , which indicates the presence of bioactive compounds in it. The GC/MS analysis of some fractions obtained by continuous chromatographic separation, allowed identification of metabolites, such that: ( Z -9-octadecenoic acid methyl ester, octadecenoic acid methyl ester, 1-methyl-4-ethoxy-δ(3-pyrrolin-2-one, endo-1-bourbonanol, dibutylphtalate, 4,5-epoxy-1-isopropyl-4-methyl- 1-cyclohexene, 1,3,3-trimethyl-7-oxabcyclo[2.2.1]heptane-2-carboxylic acid ethyl ester, 2,6-dimethyl-2-trans- 6-octadiene, farnesol, 3β-cholesta-5,22-dien-3-ol, cholesterol, (3β,22 E ,24S-ergosta-5,22-dien-3-ol, (3β,5α-2- methylenecholestan-3-ol, 3-hidroxylongifolol, by comparison with the WILEY and NIST databases and the study of the fragmentation patterns of their mass spectra.

  8. North Atlantic octocorals: Distribution, Ecology and Phylogenetics

    OpenAIRE

    Morris, Kirsty Janet

    2011-01-01

    Most studies of deep-sea benthic fauna have concentrated on soft sediments with little sampling in rocky areas and even less on non-vent mid-ocean ridges and within submarine canyons, mainly as a result of difficulty accessing them. To assess the distribution and abundance of cold-water corals along an Axial Volcanic Ridges along the Mid-Atlantic ridge at 45oN 27oW, and within the Whittard Canyon along the Irish Margin video footage from the ROV Isis taken during a three scientific cruises wa...

  9. Metabolitos secundarios, letalidad y actividad antimicrobiana de los extractos de tres corales y tres moluscos marinos de Sucre, Venezuela

    Directory of Open Access Journals (Sweden)

    Gabriel Ordaz

    2010-06-01

    Full Text Available A los extractos crudos de los octocorales Eunicea sp., Muricea sp. y Pseudopterogorgia acerosa y de los moluscos Pteria colymbus, Phylonotus pomum y Chicoreus brevifrons, se les realizaron pruebas químicas, las cuales evidenciaron en todos ellos, la presencia de metabolitos secundarios como alcaloides, esteroles insaturados y triterpenos pentacíclicos. Sólo se detectaron sesquiterpenlactonas, saponinas, taninos, glicósidos cianogénicos y glicósidos cardiotónicos en algunos de los extractos de los octocorales, lo cual sugiere que la biosíntesis de estos metabolitos es propia de este grupo de organismos. Asimismo, se evaluó la actividad letal y antimicrobiana de los extractos de los octocorales y moluscos. En el bioensayo de letalidad, todos los extractos resultaron letales frente al crustáceo Artemia salina (CL50Secondary metabolites, lethality and antimicrobial activity of extracts from three corals and three marine mollusks from Sucre, Venezuela. The study of biochemical activity of extracts obtained from marine organisms is gaining interest as some have proved to have efficient health or industrial applications. To evaluate lethality and antimicrobial activities, some chemical tests were performed on crude extracts of the octocorals Eunicea sp., Muricea sp. and Pseudopterogorgia acerosa and the mollusks Pteria colymbus, Phyllonotus pomum and Chicoreus brevifrons, collected in Venezuelan waters. The presence of secondary metabolites like alkaloids, unsaturated sterols and pentacyclic triterpenes in all invertebrates, was evidenced. Additionally, sesquiterpenlactones, saponins, tannins, cyanogenic and cardiotonic glycosides were also detected in some octocoral extracts, suggesting that biosynthesis of these metabolites is typical in this group. From the lethality bioassays, all extracts resulted lethal to Artemia salina (LC50<1.000μg/ml with an increased of lethal activity with exposition time. P. pomum extract showed the highest

  10. Oxygen consumption in Mediterranean octocorals under different temperatures

    NARCIS (Netherlands)

    Previati, M.; Scinto, A.; Cerrano, C.; Osinga, R.

    2010-01-01

    Ecosystem resilience to climate anomalies is related to the physiological plasticity of organisms. To characterize the physiological response of some common Mediterranean gorgonians to fluctuations in temperature, four species (Paramuricea clavata, Eunicella singularis, Eunicella cavolinii and

  11. Nine microsatellite loci developed from the octocoral, Paragorgia arborea

    Science.gov (United States)

    Coykendall, D. Katharine; Morrison, Cheryl L.

    2015-01-01

    Paragorgia arborea, or bubblegum coral, occurs in continental slope habitats worldwide, which are increasingly threatened by human activities such as energy development and fisheries practices. From 101 putative loci screened, nine microsatellite markers were developed from samples taken from Baltimore canyon in the western North Atlantic Ocean. The number of alleles ranged from two to thirteen per locus and each displayed equilibrium. These nuclear resources will help further research on population connectivity in threatened coral species where mitochondrial markers are known to lack fine-scale genetic diversity.

  12. ANÁLISIS POR CG/EM Y ACTIVIDAD ANTIMICROBIANA DE ALGUNAS FRACCIONES DEL EXTRACTO EN ACETATO DE ETILO DE Pseudopterogorgia acerosa I ANALYSIS BY GC/MS AND ANTIMICROBIAL ACTIVITY OF SOME ChROMATOGRAPhIC FRACTIONS OF ThE Pseudopterogorgia acerosa EThYL ACETATE EXTRACT

    Directory of Open Access Journals (Sweden)

    Gabriel Ordaz

    2014-02-01

    Full Text Available Psudopterogorgia acerosa, showed antimicrobial activity against Salmonella enteritidis, Bacillus subtlis, Staphylococcus aureus and Citrobacter freundii bacteria and the fungus Candida albicans, indicating the presence of bioactive constituents in these fractions. Moreover, the GC/MS analysis of some subfractions obtained through continuous chromatographic separation., allowed the identification of the constituents: pristane, bis(3,5,5-trimethylhexyl ether, 4-octadecanolide, tricloroeicosylsilane, (2-endo,7-exo-7-ethyl-2,4-dimethyl-6,8-dioxabycicle[3,2,1]oct-3-ene,1-methoxy-12-octoherbertene, butylphtalylbutylglycolate, N-methyl-N-(4-(4-methoxy-1-hexahydropyridil-2-butynylacetamide, diisobutylphtalate, 3-(4-(diphenylmethylphenyl-1-phenyl-4,4-dimethyl-1-pentanone, by comparison with WILEY databases and the study of the patterns of fragmentation of their mass spectra

  13. Development of long-term primary cell aggregates from Mediterranean octocorals.

    Science.gov (United States)

    Huete-Stauffer, Carla; Valisano, Laura; Gaino, Elda; Vezzulli, Luigi; Cerrano, Carlo

    2015-09-01

    In lower metazoans, the aggregative properties of dissociated cells leading to in vitro stable multicellular aggregates have furnished a remarkable experimental material to carry out investigations in various research fields. One of the main expectations is to find good models for the study in vitro of the first steps of biomineralization processes. In this study, we examined five common Mediterranean gorgonians (Paramuricea clavata, Corallium rubrum, Eunicella singularis, Eunicella cavolinii, and Eunicella verrucosa) using mechanical cell aggregate production techniques. In particular, we investigated the conditions of aggregate formation, their number and survival in experimental conditions, the DNA synthesizing activity using 5'-bromo-2'-deoxyuridine (BrdU) tests, and the response to calcein addition and observed the secretion of newly formed sclerites. The BrdU tests showed that cell proliferation depends on the size of aggregates and on the presence/absence of symbiotic zooxanthellae. With epifluorescent and confocal imaging from calcein addition assays, we observed the presence of calcium ions within cells, a possible clue for prediction of sclerite formation or calcium deposition. The species-specific efficiency in production of cell aggregates is correlated to the size of polyps, showing that the higher density of polyps and their diameter correspond to higher production of cell aggregates. Regarding the long-term maintenance, we obtained the best results from E. singularis, which formed multicellular aggregates of 0.245 mm ± 0.086 mm in size and maintained symbiotic association with zooxanthellae throughout the experimental run. Formation of sclerites within aggregates opens a wide field of investigation on biomineralization, since de novo sclerites were observed around 30 d after the beginning of the experiment.

  14. Life history and viability of a long-lived marine invertebrate: the octocoral Paramuricea clavata.

    Science.gov (United States)

    Linares, Cristina; Doak, Daniel F; Coma, Rafel; Díaz, David; Zabala, Mikel

    2007-04-01

    The red gorgonian Paramuricea clavata is a long-lived, slow-growing sessile invertebrate of ecological and conservation importance in the northwestern Mediterranean Sea. We develop a series of size-based matrix models for two Paramuricea clavata populations. These models were used to estimate basic life history traits for this species and to evaluate the viability of the red gorgonian populations we studied. As for many other slow-growing species, sensitivity and elasticity analysis demonstrate that gorgonian population growth is far more sensitive to changes in survival rates than to growth, shrinkage, or reproductive rates. The slow growth and low mortality of red gorgonians results in low damping ratios, indicating slow convergence to stable size structures (at least 50 years). The stable distributions predicted by the model did not differ from the observed ones. However, our simulations point out the fragility of this species, showing both populations in decline and high risk of extinction over moderate time horizons. These declines appear to be related to a recent increase in anthropogenic disturbances. Relative to their life span, the values of recruitment elasticity for Paramuricea clavata are lower than those reported for other marine organisms but are similar to those reported for some long-lived plants. These values and the delayed age of sexual maturity, in combination with the longevity of the species, show a clear fecundity/mortality trade-off. Full demographic studies of sessile marine species are quite scarce but can provide insight into population dynamics and life history patterns for these difficult and under-studied species. While our work shows clear results for the red gorgonian, the variability in some of our estimates suggest that future work should include data collection over longer temporal and spatial scales to better understand the long-term effects of natural and anthropogenic disturbances on red gorgonian populations.

  15. A taxonomic survey of Saudi Arabian Red Sea octocorals (Cnidaria: Alcyonacea)

    KAUST Repository

    Haverkort-Yeh, Roxanne D.; McFadden, Catherine S.; Benayahu, Yehuda; Berumen, Michael L.; Halá sz, Anna; Toonen, Robert J.

    2013-01-01

    direct comparison of biodiversity from this location to others for which molecular data are available, and (2) facilitate future identifications of these taxa. Finally, this preliminary phylogeny of sampled taxa provides insights on the resolution

  16. New C sub(21) Delta sup(20) pregnanes, inhibitors of mitochondrial respiratory chain,from Indopacific octocoral Carijoa sp.

    Digital Repository Service at National Institute of Oceanography (India)

    Ciavatta, M.L.; Gresa, M.P.L.; Manzo, E.; Gavagnin, M.; Wahidullah, S.; Cimino, G.

    , m), 1.65 (H-8, m), 1.58 (H-16b, m), 1.28 (H-15b, m), 1.24 (H 3 -19, s), 1.10 (H-9, m), 1.08 (H-7b, m), 1.07 (H-12b, m), 1.02(H-14, m), 0.67 (H 3 -18, s); 13 C NMR (75.13MHz, CDCl 3 ): d 186.5 (C-3, s), 169.0 (C-5, s), 155.9 (C-1, d), 139.3 (C-20, d...), 127.5 (C- 2, d), 123.8 (C-4, d), 114.9 (C-21, t), 55.1 (C-17, d), 54.6 (C-14, d), 52.7 (C-9, d), 43.6 (C-10 and C-13, s·2), 37.1 (C-12, t), 35.7 (C-8, d), 33.7 (C-7, t), 32.9 (C-6, t), 27.1 (C-16, t), 24.9 (C-15, t), 22.5 (C-11, t), 18.7 (C-19, q), 12...

  17. Octocoral Species Richness for the Florida Keys National Marine Sanctuary from 1999-2009 (NODC Accession 0123059)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The dataset includes species richness of benthic branching and encrusting gorgonians collected from multiple habitat types across the south Florida shelf, inside and...

  18. 77 FR 73219 - Endangered and Threatened Wildlife and Plants: Proposed Listing Determinations for 82 Reef...

    Science.gov (United States)

    2012-12-07

    ... octocorals, they have near microscopic polyps containing tentacles with stinging cells. Reef-building coral... within the mother colony (brooders) or outside of the mother colony, adrift in the ocean (broadcast...

  19. 75 FR 23245 - Gulf of Mexico Fishery Management Council; Public Meeting

    Science.gov (United States)

    2010-05-03

    ... alternatives for allowable octocorals, stone crab claws, royal red shrimp, and the Peneid shrimp species in the Generic ACL/AM Amendment options paper; and (7) discuss possible strategies to resolve differences between...

  20. Seasonal Stability in the Microbiomes of Temperate Gorgonians and the Red Coral Corallium rubrum Across the Mediterranean Sea

    KAUST Repository

    van de Water, Jeroen A. J. M.; Voolstra, Christian R.; Rottier, Cecile; Cocito, Silvia; Peirano, Andrea; Allemand, Denis; Ferrier-Pagè s, Christine

    2017-01-01

    dynamics were observed between locations and could primarily be attributed to locally variant bacteria. Overall, our data provide further evidence of the intricate symbiotic relationships that exist between Mediterranean octocorals and their associated

  1. The invasive snowflake coral (Carijoa riisei in the Tropical Eastern Pacific, Colombia

    Directory of Open Access Journals (Sweden)

    Juan Armando Sánchez

    2014-02-01

    Full Text Available Carijoa riisei (Octocorallia: Cnidaria, a western Atlantic species, has been reported in the Pacific as an invasive species for nearly forty years. C. riisei has been recently observed overgrowing native octocorals at several rocky-coral littorals in the Colombian Tropical Eastern Pacific-(TEP. C. riisei has inhabited these reefs for at least 15 years but the aggressive overgrowth on other octocorals have been noted until recently. Here, we surveyed for the first time the distribution and inter-specific aggression by C. riisei in both coastal and oceanic areas colonized in the Colombian TEP (Malpelo, Gorgona and Cabo Corrientes, including preliminary multiyear surveys during 2007-2013. We observed community-wide octocoral mortalities (including local extinction of some Muricea spp. and a steady occurrence of competing and overgrowing Pacifigorgia seafans and Leptogorgia seawhips. In Gorgona Island, at two different sites, over 87% (n=77 tagged colonies of octocorals (Pacifigorgia spp. and Leptogorgia alba died as a result of C. riisei interaction and/or overgrowth between 2011 and 2013. C. riisei overgrows octocorals with an estimate at linear growth rate of about 1cm m-1. The aggressive overgrowth of this species in TEP deserves more attention and regular monitoring programs. Rev. Biol. Trop. 62 (Suppl. 1: 199-207. Epub 2014 February 01.

  2. Fish, fans and hydroids: host species of pygmy seahorses

    Directory of Open Access Journals (Sweden)

    Bastian Reijnen

    2011-06-01

    Full Text Available An overview of the octocoral and hydrozoa host species of pygmy seahorses is provided, based on recently collected data for H. bargibanti, H. denise and H. pontohi and literature records. Seven new interspecific host-species associations are recognized, and an overview of the so far documented number of host species is given. Detailed re-examination of octocoral type material and a review of the taxonomic history are included, as a baseline for further studies. The host-specificity and colour morphs of pygmy seahorses are discussed, as well as the validity of (previous identifications and conservations issues.

  3. Fish, fans and hydroids: host species of pygmy seahorses.

    Science.gov (United States)

    Reijnen, Bastian T; van der Meij, Sancia E T; van Ofwegen, Leen P

    2011-01-01

    An overview of the octocoral and hydrozoan host species of pygmy seahorses is provided based on literature records and recently collected field data for Hippocampus bargibanti, Hippocampus denise and Hippocampus pontohi. Seven new associations are recognized and an overview of the so far documented host species is given. A detailed re-examination of octocoral type material and a review of the taxonomic history of the alcyonacean genera Annella (Subergorgiidae) and Muricella (Acanthogorgiidae) are included as baseline for future revisions. The host specificity and colour morphs of pygmy seahorses are discussed, as well as the reliability of (previous) identifications and conservation issues.

  4. Flow-dependent growth in the zooxanthellate soft coral Sinularia flexibilis

    NARCIS (Netherlands)

    Khalesi, M.K.; Beeftink, H.H.; Wijffels, R.H.

    2007-01-01

    Growth characteristics of colonies of the branching zooxanthellate octocoral Sinularia flexibilis, with potential pharmaceutical importance, were measured over a range of water velocities. The highest mean specific growth rate (¿ d¿ 1) was found at a flow velocity of 11 cm s¿ 1. An optimal range of

  5. Seasonal Stability in the Microbiomes of Temperate Gorgonians and the Red Coral Corallium rubrum Across the Mediterranean Sea.

    Science.gov (United States)

    van de Water, Jeroen A J M; Voolstra, Christian R; Rottier, Cecile; Cocito, Silvia; Peirano, Andrea; Allemand, Denis; Ferrier-Pagès, Christine

    2018-01-01

    Populations of key benthic habitat-forming octocoral species have declined significantly in the Mediterranean Sea due to mass mortality events caused by microbial disease outbreaks linked to high summer seawater temperatures. Recently, we showed that the microbial communities of these octocorals are relatively structured; however, our knowledge on the seasonal dynamics of these microbiomes is still limited. To investigate their seasonal stability, we collected four soft gorgonian species (Eunicella singularis, Eunicella cavolini, Eunicella verrucosa and Leptogorgia sarmentosa) and the precious red coral (Corallium rubrum) from two coastal locations with different terrestrial impact levels in the Mediterranean Sea, and used next-generation amplicon sequencing of the 16S rRNA gene. The microbiomes of all soft gorgonian species were dominated by the same 'core microbiome' bacteria belonging to the Endozoicomonas and the Cellvibrionales clade BD1-7, whereas the red coral microbiome was primarily composed of 'core' Spirochaetes, Oceanospirillales ME2 and Parcubacteria. The associations with these bacterial taxa were relatively consistent over time at each location for each octocoral species. However, differences in microbiome composition and seasonal dynamics were observed between locations and could primarily be attributed to locally variant bacteria. Overall, our data provide further evidence of the intricate symbiotic relationships that exist between Mediterranean octocorals and their associated microbes, which are ancient and highly conserved over both space and time, and suggest regulation of the microbiome composition by the host, depending on local conditions.

  6. Browse Title Index

    African Journals Online (AJOL)

    Items 1 - 25 of 1853 ... (Cnidaria: Actiniaria) a mobile sea anemone attacking octocorals, Abstract PDF. Karin Riemann-Zürneck, Charles L. Griffiths. Vol 35, No 2 (2000), Kroyeria deetsi n.sp. (Kroyeriidae: Siphonostomatoida), a parasitic copepod infecting gills of spinner sharks, Carcharhinus brevipinna (Müller & Henle, 1839), ...

  7. African Zoology - Vol 34, No 4 (1999)

    African Journals Online (AJOL)

    Korsaranthus natalensis (Carlgren, 1938) nov. comb. (Cnidaria: Actiniaria) a mobile sea anemone attacking octocorals · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. Karin Riemann-Zürneck, Charles L. Griffiths, 190-196 ...

  8. Coral reef condition and benthic sedimentation threat in four regions of south Puerto Rico

    Science.gov (United States)

    Scleractinian corals, gorgonian octocorals, sponges and fishes were assessed near the cities of LaParguera, Guánica, Guayanilla, and Jobos along the southern coast of Puerto Rico in November – December 2010. Survey sites were targeted near areas with varying benthic...

  9. ROLE OF CORAL DISEASES AND ANTHROPOGENIC STRESSORS ON TROPIC MARINE CORAL REEFS

    Science.gov (United States)

    Stony (scleractinian) and soft (octocorals) corals throughout the Western Atlantic have been affected by several fatal diseases in the last two decades. In many locations the communities have not recovered from these diseases and the ecosystem has permanently changed. Several hyp...

  10. Seasonal Stability in the Microbiomes of Temperate Gorgonians and the Red Coral Corallium rubrum Across the Mediterranean Sea

    KAUST Repository

    van de Water, Jeroen A. J. M.

    2017-07-05

    Populations of key benthic habitat-forming octocoral species have declined significantly in the Mediterranean Sea due to mass mortality events caused by microbial disease outbreaks linked to high summer seawater temperatures. Recently, we showed that the microbial communities of these octocorals are relatively structured; however, our knowledge on the seasonal dynamics of these microbiomes is still limited. To investigate their seasonal stability, we collected four soft gorgonian species (Eunicella singularis, Eunicella cavolini, Eunicella verrucosa and Leptogorgia sarmentosa) and the precious red coral (Corallium rubrum) from two coastal locations with different terrestrial impact levels in the Mediterranean Sea, and used next-generation amplicon sequencing of the 16S rRNA gene. The microbiomes of all soft gorgonian species were dominated by the same \\'core microbiome\\' bacteria belonging to the Endozoicomonas and the Cellvibrionales clade BD1-7, whereas the red coral microbiome was primarily composed of \\'core\\' Spirochaetes, Oceanospirillales ME2 and Parcubacteria. The associations with these bacterial taxa were relatively consistent over time at each location for each octocoral species. However, differences in microbiome composition and seasonal dynamics were observed between locations and could primarily be attributed to locally variant bacteria. Overall, our data provide further evidence of the intricate symbiotic relationships that exist between Mediterranean octocorals and their associated microbes, which are ancient and highly conserved over both space and time, and suggest regulation of the microbiome composition by the host, depending on local conditions.

  11. A redescription of the specimens of “Telesto humilis” (Octocorallia) collected by Prince Albert Ier of Monaco, with the descritpion of four new species

    NARCIS (Netherlands)

    Weinberg, Steven

    1990-01-01

    Four new octocoral species, Telestula stocki, Telestula batoni, Telestula verseveldti, and Telestula kuekenthali are described and illustrated and a redescription is given of Telesto humilis Thomson, 1927. All the species mentioned were collected during expeditions by Prince Albert Ier of Monaco in

  12. The light-dependent behaviour of planula larvae of Eunicella singularis and Corallium rubrum and its implication for octocorallian ecology

    NARCIS (Netherlands)

    Weinberg, Steven

    1979-01-01

    The behaviour of Mediterranean octocoral planulae was studied in light-dark situations and in a light gradient. Larvae of Eunicella singularis (Esper, 1794) reacted photopositively but it is uncertain which mechanism (klinotaxis or klinokinesis) determines this property. The blind larvae probably

  13. Autecology of shallow-water Octocorallia from Mediterranean rocky substrata, I. The Banyuls area

    NARCIS (Netherlands)

    Weinberg, Steven

    1979-01-01

    The autecology of eleven mediterranean octocoral species (3 Stolonifera, 4 Alcyonacea, 4 Gorgonacea) was studied near Banyuls-sur-Mer (southern France). Field observations were carried out by means of SCUBA-diving in forty underwater stations. The ecological amplitude of each species was determined

  14. Systematics of Vampyressa melissa Thomas, 1926 (Chiroptera, Phyllostomidae), with descriptions of two new species of Vampyressa

    Science.gov (United States)

    Tavares, Valéria da C.; Gardner, Alfred L.; Ramírez-Chaves, Héctor E.; Velazco, Paúl M.

    2014-01-01

    Vampyressa melissa is a poorly known phyllostomid bat listed as vulnerable by the International Union for Conservation of Nature (IUCN). Since its description in 1926, fewer than 40 V. melissa have been reported in the literature, and less than half of these may have been correctly identified. During revisionary studies of Vampyressa, we uncovered two previously unrecognized species related to V. melissa, all associated with higher elevation habitats (>1400 m), one from the Andes of Colombia (Vampyressa sinchi, new species) and the other from western Panama (Vampyressa elisabethae, new species) revealing that V. melissa, as traditionally defined, is a composite of at least three species. In this paper, we provide a restricted diagnosis for the genus Vampyressa, an emended diagnosis of V. melissa, and descriptions of the two new species. The separation of these frugivorous bats, previously identified as V. melissa, into three isolated upper-elevation species, each having restricted distributions further highlights their fragile conservation status.

  15. Aspergillosis in the common sea fan Gorgonia ventalina: isolation of waterborne hyphae and spores.

    Science.gov (United States)

    Troeger, Victoria J; Sammarco, Paul W; Caruso, John H

    2014-07-03

    The octocoral disease aspergillosis is caused by the terrestrial fungus Aspergillus sydowii. The possibility of secondary (horizontal) transmission of aspergillosis among common sea fans Gorgonia ventalina would require waterborne transmission of hyphae and/or spores. A laboratory filtration experiment confirmed that fungal hyphae and spores were shed into the water by infected fans. This suggests that secondary infection might be possible in this species. It remains to be determined whether healthy fans actually develop aspergillosis after contact with hyphae-laden water.

  16. Diversity of zoanthids (anthozoa: hexacorallia) on Hawaiian seamounts: description of the Hawaiian gold coral and additional zoanthids.

    Science.gov (United States)

    Sinniger, Frederic; Ocaña, Oscar V; Baco, Amy R

    2013-01-01

    The Hawaiian gold coral has a history of exploitation from the deep slopes and seamounts of the Hawaiian Islands as one of the precious corals commercialised in the jewellery industry. Due to its peculiar characteristic of building a scleroproteic skeleton, this zoanthid has been referred as Gerardia sp. (a junior synonym of Savalia Nardo, 1844) but never formally described or examined by taxonomists despite its commercial interest. While collection of Hawaiian gold coral is now regulated, globally seamounts habitats are increasingly threatened by a variety of anthropogenic impacts. However, impact assessment studies and conservation measures cannot be taken without consistent knowledge of the biodiversity of such environments. Recently, multiple samples of octocoral-associated zoanthids were collected from the deep slopes of the islands and seamounts of the Hawaiian Archipelago. The molecular and morphological examination of these zoanthids revealed the presence of at least five different species including the gold coral. Among these only the gold coral appeared to create its own skeleton, two other species are simply using the octocoral as substrate, and the situation is not clear for the final two species. Phylogenetically, all these species appear related to zoanthids of the genus Savalia as well as to the octocoral-associated zoanthid Corallizoanthus tsukaharai, suggesting a common ancestor to all octocoral-associated zoanthids. The diversity of zoanthids described or observed during this study is comparable to levels of diversity found in shallow water tropical coral reefs. Such unexpected species diversity is symptomatic of the lack of biological exploration and taxonomic studies of the diversity of seamount hexacorals.

  17. Diversity of zoanthids (anthozoa: hexacorallia on Hawaiian seamounts: description of the Hawaiian gold coral and additional zoanthids.

    Directory of Open Access Journals (Sweden)

    Frederic Sinniger

    Full Text Available The Hawaiian gold coral has a history of exploitation from the deep slopes and seamounts of the Hawaiian Islands as one of the precious corals commercialised in the jewellery industry. Due to its peculiar characteristic of building a scleroproteic skeleton, this zoanthid has been referred as Gerardia sp. (a junior synonym of Savalia Nardo, 1844 but never formally described or examined by taxonomists despite its commercial interest. While collection of Hawaiian gold coral is now regulated, globally seamounts habitats are increasingly threatened by a variety of anthropogenic impacts. However, impact assessment studies and conservation measures cannot be taken without consistent knowledge of the biodiversity of such environments. Recently, multiple samples of octocoral-associated zoanthids were collected from the deep slopes of the islands and seamounts of the Hawaiian Archipelago. The molecular and morphological examination of these zoanthids revealed the presence of at least five different species including the gold coral. Among these only the gold coral appeared to create its own skeleton, two other species are simply using the octocoral as substrate, and the situation is not clear for the final two species. Phylogenetically, all these species appear related to zoanthids of the genus Savalia as well as to the octocoral-associated zoanthid Corallizoanthus tsukaharai, suggesting a common ancestor to all octocoral-associated zoanthids. The diversity of zoanthids described or observed during this study is comparable to levels of diversity found in shallow water tropical coral reefs. Such unexpected species diversity is symptomatic of the lack of biological exploration and taxonomic studies of the diversity of seamount hexacorals.

  18. Limitations of mitochondrial gene barcoding in Octocorallia.

    Science.gov (United States)

    McFadden, Catherine S; Benayahu, Yehuda; Pante, Eric; Thoma, Jana N; Nevarez, P Andrew; France, Scott C

    2011-01-01

    The widespread assumption that COI and other mitochondrial genes will be ineffective DNA barcodes for anthozoan cnidarians has not been well tested for most anthozoans other than scleractinian corals. Here we examine the limitations of mitochondrial gene barcoding in the sub-class Octocorallia, a large, diverse, and ecologically important group of anthozoans. Pairwise genetic distance values (uncorrected p) were compared for three candidate barcoding regions: the Folmer region of COI; a fragment of the octocoral-specific mitochondrial protein-coding gene, msh1; and an extended barcode of msh1 plus COI with a short, adjacent intergenic region (igr1). Intraspecific variation was barcodes, and there was no discernible barcoding gap between intra- and interspecific p values. In a case study to assess regional octocoral biodiversity, COI and msh1 barcodes each identified 70% of morphospecies. In a second case study, a nucleotide character-based analysis correctly identified 70% of species in the temperate genus Alcyonium. Although interspecific genetic distances were 2× greater for msh1 than COI, each marker identified similar numbers of species in the two case studies, and the extended COI + igr1 + msh1 barcode more effectively discriminated sister taxa in Alcyonium. Although far from perfect for species identification, a COI + igr1 + msh1 barcode nonetheless represents a valuable addition to the depauperate set of characters available for octocoral taxonomy. © 2010 Blackwell Publishing Ltd.

  19. The unforgotten sisters female astronomers and scientists before Caroline Herschel

    CERN Document Server

    Bernardi, Gabriella

    2016-01-01

    Taking inspiration from Siv Cedering’s poem in the form of a fictional letter from Caroline Herschel that refers to “my long, lost sisters, forgotten in the books that record our science”, this book tells the lives of twenty-five female scientists, with specific attention to astronomers and mathematicians. Each of the presented biographies is organized as a kind of "personal file" which sets the biographee’s life in its historical context, documents her main works, highlights some curious facts, and records citations about her. The selected figures are among the most representative of this neglected world, including such luminaries as Hypatia of Alexandra, Hildegard of Bingen, Elisabetha Hevelius, and Maria Gaetana Agnesi. They span a period of about 4000 years, from En HeduAnna, the Akkadian princess, who was one of the first recognized female astronomers, to the dawn of the era of modern astronomy with Caroline Herschel and Mary Somerville. The book will be of interest to all who wish to learn more ...

  20. Três biografias quinhentistas da Rainha Santa Isabel

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    Helena Costa Toipa

    2016-12-01

    Full Text Available Dando continuidade aos esforços de canonização de D. Isabel de Aragão, D. João III obteve do Papa, em 1556, a autorização para alargar o culto da já beata D. Isabel a todo o reino. Solicitou, então, aos responsáveis dos mosteiros portugueses, nomeadamente à abadessa do mosteiro de Santa Clara, a composição de uma biografia da rainha, a partir de documentos existentes nesse mosteiro. Surgiram, então, três biografias, todas inspiradas nos referidos documentos: De Vita et Moribus Beatae Elisabethae Lusitaniae Reginae do padre jesuíta Pedro João Perpinhão; Vida e milagres da gloriosa Raynha sancta Ysabel, molher do catholico Rey dom Dinis sexto de Portugal, editada pelos mordomos da Confraria da Rainha Santa Isabel, e “ Vida da Bemaventurada sancta Isabel Raynha de Portugal”, de Frei Marcos de Lisboa, inclusa na Segunda Parte das suas Chronicas da Ordemdos Frades Menores.

  1. Zoantharians (Hexacorallia: Zoantharia Associated with Cold-Water Corals in the Azores Region: New Species and Associations in the Deep Sea

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    Marina Carreiro-Silva

    2017-04-01

    Full Text Available Zoantharians are a group of cnidarians that are often found in association with marine invertebrates, including corals, in shallow and deep-sea environments. However, little is known about deep-sea zoantharian taxonomy, specificity and nature of their associations with their coral hosts. In this study, analyses of molecular data (mtDNA COI, 16S, and 12S rDNA coupled with ecological and morphological characteristics were used to examine zoantharian specimens associated with cold-water corals (CWC at depths between 110 and 800 m from seamounts and island slopes in the Azores region. The zoantharians examined were found living in association with stylasterids, antipatharians and octocorals. From the collected specimens, four new species were identified: (1 Epizoanthus martinsae sp. n. associated with the antipatharian Leiopathes sp.; (2 Parazoanthus aliceae sp. n. associated with the stylasterid Errina dabneyi (Pourtalès, 1871; (3 Zibrowius alberti sp. n. associated with octocorals of the family Primnoidae [Paracalyptrophora josephinae (Lindström, 1877] and the family Plexauridae (Dentomuricea aff. meteor Grasshoff, 1977; (4 Hurlizoanthus hirondelleae sp. n. associated with the primnoid octocoral Candidella imbricata (Johnson, 1862. In addition, based on newly collected material, morphological and molecular data and phylogenic reconstruction, the zoantharian Isozoanthus primnoidus Carreiro-Silva, Braga-Henriques, Sampaio, de Matos, Porteiro & Ocaña, 2011, associated with the primnoid octocoral Callogorgia verticillata (Pallas, 1766, was reclassified as Zibrowius primnoidus comb. nov. The zoantharians, Z. primnoidus comb. nov., Z. alberti sp. n., and H. hirondelleae sp. n. associated with octocorals showed evidence of a parasitic relationship, where the zoantharian progressively eliminates gorgonian tissue and uses the gorgonian axis for structure and support, and coral sclerites for protection. In contrast, the zoantharian P. aliceae sp. n

  2. Responses of the tropical gorgonian coral Eunicea fusca to ocean acidification conditions

    Science.gov (United States)

    Gómez, C. E.; Paul, V. J.; Ritson-Williams, R.; Muehllehner, N.; Langdon, C.; Sánchez, J. A.

    2015-06-01

    Ocean acidification can have negative repercussions from the organism to ecosystem levels. Octocorals deposit high-magnesium calcite in their skeletons, and according to different models, they could be more susceptible to the depletion of carbonate ions than either calcite or aragonite-depositing organisms. This study investigated the response of the gorgonian coral Eunicea fusca to a range of CO2 concentrations from 285 to 4,568 ppm (pH range 8.1-7.1) over a 4-week period. Gorgonian growth and calcification were measured at each level of CO2 as linear extension rate and percent change in buoyant weight and calcein incorporation in individual sclerites, respectively. There was a significant negative relationship for calcification and CO2 concentration that was well explained by a linear model regression analysis for both buoyant weight and calcein staining. In general, growth and calcification did not stop in any of the concentrations of pCO2; however, some of the octocoral fragments experienced negative calcification at undersaturated levels of calcium carbonate (>4,500 ppm) suggesting possible dissolution effects. These results highlight the susceptibility of the gorgonian coral E. fusca to elevated levels of carbon dioxide but suggest that E. fusca could still survive well in mid-term ocean acidification conditions expected by the end of this century, which provides important information on the effects of ocean acidification on the dynamics of coral reef communities. Gorgonian corals can be expected to diversify and thrive in the Atlantic-Eastern Pacific; as scleractinian corals decline, it is likely to expect a shift in these reef communities from scleractinian coral dominated to octocoral/soft coral dominated under a "business as usual" scenario of CO2 emissions.

  3. Rapid change with depth in megabenthic structure-forming communities of the Makapu'u deep-sea coral bed

    Science.gov (United States)

    Long, Dustin J.; Baco, Amy R.

    2014-01-01

    Seamounts are largely unexplored undersea mountains rising abruptly from the ocean floor, which can support an increased abundance and diversity of organisms. Deep-sea corals are important benthic structure-formers on current-swept hard substrates in these habitats. While depth is emerging as a factor structuring the fauna of seamounts on a large spatial scale, most work addressing deep-sea coral and seamount community structure has not considered the role of small-scale variation in species distributions. Video from six ROV dives over a depth range of ~320-530 m were analyzed to assess the diversity and density of benthic megafaunal invertebrates across the Makapu'u deep-sea coral bed, offshore of Oahu, Hawaii. At the same time, the physical environment along the dive track was surveyed to relate biotic patterns with abiotic variables including depth, aspect, rugosity, substrate, slope and relief to test the factors structuring community assemblages. Despite the narrow range examined, depth was found to be the strongest structuring gradient, and six unique macrobenthic communities were found, with a 93% faunal dissimilarity over the depth surveyed. Relief, rugosity and slope were also factors in the final model. Alcyonacean octocorals were the dominant macrofaunal invertebrates at all but the deepest depth zone. The commercially harvested precious coral C. secundum was the dominant species at depths 370-470 m, with a distribution that is on average deeper than similar areas. This may be artificial due to the past harvesting of this species on the shallower portion of its range. Primnoid octocorals were the most abundant octocoral family overall. This work yields new insight on the spatial ecology of seamounts, pointing out that community changes can occur over narrow depth ranges and that communities can be structured by small-scale physiography.

  4. A new species of Ovabunda (Octocorallia, Xeniidae from the Andaman Sea, Thailand with notes on the biogeography of this genus

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    Michael Janes

    2014-08-01

    Full Text Available A survey of xeniid octocorals was carried out in the waters off Southwestern Thailand in September, 2007. Microscopic investigation of the colonies revealed that three specimens belonged to the genus Ovabunda. Gross morphological examination is presented here accompanied by scanning electron micrographs of the sclerites. Molecular phylogenetic analysis showed identical genotypes at mtMutS, COI, and 28S rDNA for all three specimens and supports their generic assignment. Colony size and shape, sclerite size, and pinnule arrangement differ from nominal species of Ovabunda and thus a new species, O. andamanensis is introduced here. This work also presents a new eastern geographical record for the genus Ovabunda.

  5. Seawater Carbonate Chemistry of Deep-sea Coral Beds off the Northwestern Hawaiian Islands

    Science.gov (United States)

    Brooks, J.; Shamberger, K.; Roark, E. B.; Miller, K.; Baco-Taylor, A.

    2016-02-01

    Many species of deep-sea octocorals produce calcium carbonate (CaCO3) skeletons and form coral beds that support diverse ecosystems crucial to fisheries. The geochemistry of deep-sea coral skeletons can provide valuable paleoceanographic information on ocean circulation and nutrient cycling. Deep-sea corals in the older bottom waters of the Pacific are naturally exposed to higher carbon dioxide (CO2) concentrations and lower pH than in the Atlantic where much of the previous deep-sea coral work has occurred. Therefore, some Pacific deep-sea corals may live and calcify in waters that are corrosive to their skeletons, but there have been few current seawater carbonate chemistry measurements of the waters surrounding deep-sea coral beds to assess this. The input of anthropogenic atmospheric CO2 known as ocean acidification (OA) lowers ocean pH and causes an expansion of these corrosive waters. Seawater carbonate chemistry must be characterized before accurate predictions can be made for the effects of OA on these important ecosystems. Total Alkalinity (TA) and Dissolved Inorganic Carbon (DIC) samples were collected in the fall of 2014 and 2015 from the surface to 1450 m depth off the Northwestern Hawaiian Island chain where deep-sea octocorals are found. The partial pressure of CO2 increased and pH, calcite saturation state (Ωca) and aragonite saturation state (Ωar) decreased with increasing latitude and depth. Notably, waters were undersaturated with respect to calcite and aragonite (Ωca and Ωar less than 1) below 800 m and 500 m, respectively. Therefore, deep-sea corals below these depths must calcify in waters that are thermodynamically favorable for CaCO3 dissolution. How deep-sea octocorals cope with such adverse seawater chemistry is critical to understanding future effects of OA. It is not known whether OA is currently negatively impacting deep-sea octocorals, but their naturally acidified environments could make them particularly susceptible to OA.

  6. A new genus of soft coral (Cnidaria, Octocorallia from the Republic of Congo (Pointe-Noire Region

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    Leen P. van Ofwegen

    2014-12-01

    Full Text Available A new genus of soft coral from the Republic of Congo is described, Complexum gen. n. Nine West African octocoral species previously described in the genus Alcyonium by Tixier-Durivault (1955 are referred to this new genus, and a new species is described and figured, C. pusillum sp. n. The new species is characterized by having encrusting growth form and abundant spiny clubs in the surface of the polyparium. It colonizes shallow calcareous rocky banks (5 to 20 m depth existing in coastal water of the region of Pointe-Noire. Based on molecular phylogeny this new genus is well separated from Alcyonium species.

  7. Abundance of Corals on Offshore Oil and Gas Platforms in the Gulf of Mexico

    Science.gov (United States)

    Kolian, Stephan R.; Sammarco, Paul W.; Porter, Scott A.

    2017-08-01

    Scleractinian, octocoral, and antipatharian corals have colonized many of the offshore oil and gas platforms in the northern Gulf of Mexico. We surveyed 25 offshore oil and gas platforms for these cnidarians. Few to no corals were detected on inshore, shallow-water structures at data suggest that the offshore platforms located in waters of >25-30 m in the study area are often colonized by these corals. We recommend that structures located in deeper waters should be surveyed for coral and, if the populations are substantial, consider alternate uses for the retired platforms, and leaving them in place, when feasible.

  8. Macrobiotic Communities of Vailulu'u Seamount, Samoan Archipelago

    Science.gov (United States)

    Young, C. M.; Lee, R. W.; Pile, A. J.; Hudson, I. R.; Brooke, S. D.; Ted, P.; Staudigel, H.; Hart, S.; Bailey, B. E.; Haucke, L.; Koppers, A.; Konter, J.; Templeton, A.; Tebo, B.

    2005-12-01

    Vailulu'u, the active seamount on the hotspot at the Eastern end of the Samoan volcanic chain, was the focus of two research cruises in April and June 2005 using the Pisces V submersible. Warm-water vents on the summit of a newly formed volcanic cone in the crater supported a low-diversity community dominated by thick microbial mats and the synaphobranchid eel Dysommina rugosa. Isotope and gut analyses indicated that the eels feed not on the mats but on planktonic crustaceans imported to the system from the overlying water column. The microbial mat exhibited isotopic signatures consistent with local chemosynthesis, but not methane-based chemosynthesis; Anutrition from microbes of vent origin, while those on the outside feed on oceanic plankton. The background megafauna of the outer flank was dominated by octocorals and hexactinellid sponges, with occasional asteroids, ophiuroids and crinoids. Most megafaunal organisms collected from the outer flanks were isotopically heavy, with isotope values similar to those of non-vent deep-sea animals. However, the octocoral Anthomastis collected from low-elevation breaches on the cauldera summit were intermediate in isotopic composition, indicating that they may consume particulate material derived from vent C and N.

  9. Phylogenetic treatment and taxonomic revision of the trapdoor spider genus Aptostichus Simon (Araneae, Mygalomorphae, Euctenizidae

    Directory of Open Access Journals (Sweden)

    Jason Bond

    2012-12-01

    Full Text Available This systematic study documents the taxonomy, diversity, and distribution of 40 species of the predominately Californian trapdoor spider genus Aptostichus Simon, 1891. Thirty-three of these species are newly described: A. dantrippi, A. cabrillo, A. pennjillettei, A. asmodaeus, A. nateevansi, A. chiricahua, A. icenoglei, A. isabella, A. muiri, A. barackobamai, A. sinnombre, A. hedinorum, A. aguacaliente, A. chemehuevi, A. sarlacc, A. derhamgiulianii, A. anzaborrego, A. serrano, A. mikeradtkei, A. edwardabbeyi, A. killerdana, A. cahuilla, A. satleri, A. elisabethae, A. fornax, A. lucerne, A. fisheri, A. bonoi, A. cajalco, A. sierra, A. huntington, A. dorothealangeae, and A. chavezi. Most of these species are restricted to the California Floristic Province, a known biodiversity hotspot. Of the 40 recognized species, over half are considered to be imperiled or vulnerable and two have likely gone extinct over the past half-century; the conservation status of only 11 species is considered to be secure. Using 73 quantitative and qualitative morphological characters I propose a preliminary phylogeny for the genus that recognizes four major lineages: the Atomarius, Simus, Hesperus, and Sierra species groups. Additionally, the phylogenetic analysis indicates that adaptations favoring the invasion of the arid desert habitats of southern California have evolved multiple times across the group. The existence of both desert and non - desert species in three of the four species groups makes this genus an ideal candidate for the study of the evolutionary ecology of desert arthropods. A set of molecular characters based on the contiguous mitochondrial DNA genes 16S-tRNA valine-12S is used in an independent analysis to assist in placement of specimens into species. The taxonomy section explicitly identifies the concept employed in species delimitation. Niche based distribution models are constructed to predict the ranges of species for which an adequate number of

  10. Microbial Regulation in Gorgonian Corals

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    Laura D. Mydlarz

    2012-06-01

    Full Text Available Gorgonian corals possess many novel natural products that could potentially mediate coral-bacterial interactions. Since many bacteria use quorum sensing (QS signals to facilitate colonization of host organisms, regulation of prokaryotic cell-to-cell communication may represent an important bacterial control mechanism. In the present study, we examined extracts of twelve species of Caribbean gorgonian corals, for mechanisms that regulate microbial colonization, such as antibacterial activity and QS regulatory activity. Ethanol extracts of gorgonians collected from Puerto Rico and the Florida Keys showed a range of both antibacterial and QS activities using a specific Pseudomonas aeruginosa QS reporter, sensitive to long chain AHLs and a short chain N-acylhomoserine lactones (AHL biosensor, Chromobacterium violaceium. Overall, the gorgonian corals had higher antimicrobial activity against non-marine strains when compared to marine strains. Pseudopterogorgia americana, Pseusopterogorgia acerosa, and Pseudoplexuara flexuosa had the highest QS inhibitory effect. Interestingly, Pseudoplexuara porosa extracts stimulated QS activity with a striking 17-fold increase in signal. The stimulation of QS by P. porosa or other elements of the holobiont may encourage colonization or recruitment of specific microbial species. Overall, these results suggest the presence of novel stimulatory QS, inhibitory QS and bactericidal compounds in gorgonian corals. A better understanding of these compounds may reveal insight into coral-microbial ecology and whether a therapeutic potential exists.

  11. Phylogenetic reconstruction using secondary structures of Internal Transcribed Spacer 2 (ITS2, rDNA: finding the molecular and morphological gap in Caribbean gorgonian corals

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    Sánchez Juan A

    2007-06-01

    Full Text Available Abstract Background Most phylogenetic studies using current methods have focused on primary DNA sequence information. However, RNA secondary structures are particularly useful in systematics because they include characteristics, not found in the primary sequence, that give "morphological" information. Despite the number of recent molecular studies on octocorals, there is no consensus opinion about a region that carries enough phylogenetic resolution to solve intrageneric or close species relationships. Moreover, intrageneric morphological information by itself does not always produce accurate phylogenies; intra-species comparisons can reveal greater differences than intra-generic ones. The search for new phylogenetic approaches, such as by RNA secondary structure analysis, is therefore a priority in octocoral research. Results Initially, twelve predicted RNA secondary structures were reconstructed to provide the basic information for phylogenetic analyses; they accorded with the 6 helicoidal ring model, also present in other groups of corals and eukaryotes. We obtained three similar topologies for nine species of the Caribbean gorgonian genus Eunicea (candelabrum corals with two sister taxa as outgroups (genera Plexaura and Pseudoplexaura on the basis of molecular morphometrics of ITS2 RNA secondary structures only, traditional primary sequence analyses and maximum likelihood, and a Bayesian analysis of the combined data. The latter approach allowed us to include both primary sequence and RNA molecular morphometrics; each data partition was allowed to have a different evolution rate. In addition, each helix was partitioned as if it had evolved at a distinct rate. Plexaura flexuosa was found to group within Eunicea; this was best supported by both the molecular morphometrics and combined analyses. We suggest Eunicea flexuosa (Lamouroux, 1821 comb. nov., and we present a new species description including Scanning Electron Microscopy (SEM images of

  12. Automatic Loop Parallelization via Compiler Guided Refactoring

    DEFF Research Database (Denmark)

    Larsen, Per; Ladelsky, Razya; Lidman, Jacob

    For many parallel applications, performance relies not on instruction-level parallelism, but on loop-level parallelism. Unfortunately, many modern applications are written in ways that obstruct automatic loop parallelization. Since we cannot identify sufficient parallelization opportunities...... for these codes in a static, off-line compiler, we developed an interactive compilation feedback system that guides the programmer in iteratively modifying application source, thereby improving the compiler’s ability to generate loop-parallel code. We use this compilation system to modify two sequential...... benchmarks, finding that the code parallelized in this way runs up to 8.3 times faster on an octo-core Intel Xeon 5570 system and up to 12.5 times faster on a quad-core IBM POWER6 system. Benchmark performance varies significantly between the systems. This suggests that semi-automatic parallelization should...

  13. New name for the soft coral Alcyonium rubrum Stokvis & van Ofwegen, 2006 (Alcyonacea, Alcyoniidae: Alcyonium burmedju nom. n.

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    Íris Sampaio

    2016-09-01

    Full Text Available Alcyonium rubrum Stokvis & van Ofwegen, 2006, an encrusting soft coral (Figure 1, was described from the Northeast Atlantic Ocean based on specimens collected during the Dutch CANCAP VII Expedition to the Cape Verde Archipelago (Stokvis & van Ofwegen 2006. This species was later reported from the Azores (Braga-Henriques et al. 2013.A review on the taxonomic literature of octocorals by the first author revealed the existence of a species described from Scandinavia under the same name, Alcyonium rubrum Müller, 1776, which was also reported from Ireland (Hassal 1841. In such a case of primary homonomy, the International Code of Zoological Nomenclature Article 60, states that the junior homonym is invalid and needs to be replaced by a new name. We propose to replace Alcyonium rubrum Stokvis & van Ofwegen, 2006 by Alcyonium burmedju nom. n.

  14. Brazilian gorgonians: a source of odoriferous compounds?

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    Silvia Siag Oigman

    Full Text Available Abstract The gorgonian Phyllogorgia dilatata Esper is an octocoral known to be source of biologically active terpenes. In this study, odoriferous compounds present in P. dilatata tissues were investigated, due to their exotic olfactory notes. The search of volatile compounds was performed in a dichloromethane/methanol extract submitted to a silica gel vacuum chromatography and HPLC, yielding the isomers (Z,E and (E,E-germacrones, identified by GC/MS, 1 and 2D NMR. The stereochemistry of (E,E-germacrone, as well as its preferred conformation, was confirmed by NOESY. Sensory analysis of the two isomers revealed a fragrant, citrus, woody and weak marine odor, similar to the odor of the natural gorgonian, and (E,E-germacrone has a three times more intense aroma than the (Z,E isomer.

  15. Development of twelve microsatellite loci in the red tree corals Primnoa resedaeformis and Primnoa pacifica

    Science.gov (United States)

    Morrison, Cheryl L.; Springmann, Marcus J.; Shroades, Kelsey; Stone, Robert P.

    2015-01-01

    A suite of tetra-, penta-, and hexa-nucleotide microsatellite loci were developed from Roche 454 pyrosequencing data for the cold-water octocorals Primnoa resedaeformis and P. pacifica. Twelve of 98 primer sets tested consistently amplified in 30 P. resedaeformis samples from Baltimore Canyon (western North Atlantic Ocean) and in 24 P. pacifica samples (Shutter Ridge, eastern Gulf of Alaska). The loci displayed moderate levels of allelic diversity (average 7.5 alleles/locus) and heterozygosity (average 47 %). Levels of genetic diversity were sufficient to produce unique multi-locus genotypes and to distinguish species. These common species are long-lived (hundreds of years) and provide essential fish habitat (P. pacifica), yet populations are provided little protection from human activities. These loci will be used to determine regional patterns of population connectivity to inform effective marine spatial planning and ecosystem-based fisheries management.

  16. Abyssal fauna of the UK-1 polymetallic nodule exploration area, Clarion-Clipperton Zone, central Pacific Ocean: Cnidaria.

    Science.gov (United States)

    Dahlgren, Thomas G; Wiklund, Helena; Rabone, Muriel; Amon, Diva J; Ikebe, Chiho; Watling, Les; Smith, Craig R; Glover, Adrian G

    2016-01-01

    We present data from a DNA taxonomy register of the abyssal Cnidaria collected as part of the Abyssal Baseline (ABYSSLINE) environmental survey cruise 'AB01' to the UK Seabed Resources Ltd (UKSRL) polymetallic-nodule exploration area 'UK-1' in the eastern Clarion-Clipperton Zone (CCZ), central Pacific Ocean abyssal plain. This is the second paper in a series to provide regional taxonomic data for a region that is undergoing intense deep-sea mineral exploration for high-grade polymetallic nodules. Data were collected from the UK-1 exploration area following the methods described in Glover et al. (2015b). Morphological and genetic data are presented for 10 species and 18 records identified by a combination of morphological and genetic data, including molecular phylogenetic analyses. These included 2 primnoid octocorals, 2 isidid octocorals, 1 anemone, 4 hydroids (including 2 pelagic siphonophores accidentally caught) and a scyphozoan jellyfish (in the benthic stage of the life cycle). Two taxa matched previously published genetic sequences (pelagic siphonophores), two taxa matched published morphological descriptions (abyssal primnoids described from the same locality in 2015) and the remaining 6 taxa are potentially new species, for which we make the raw data, imagery and vouchers available for future taxonomic study. We have used a precautionary approach in taxon assignments to avoid over-estimating species ranges. The Clarion-Clipperton Zone is a region undergoing intense exploration for potential deep-sea mineral extraction. We present these data to facilitate future taxonomic and environmental impact study by making both data and voucher materials available through curated and accessible biological collections. For some of the specimens we also provide image data collected at the seabed by ROV, wich may facilitate more accurate taxon designation in coming ROV or AUV surveys.

  17. Estructura y daños en las comunidades de octocorales (Octocorallia: Alcyonacea de la Reserva Ecológica Siboney-Juticí, Santiago de Cuba, Cuba

    Directory of Open Access Journals (Sweden)

    Yunier Olivera Espinosa

    2010-12-01

    Full Text Available Se estudió la comunidad de octocorales del arrecife de macizos y canales de la Reserva Ecológica Siboney- Juticí (sur oriente de Cuba con el objetivo de caracterizar su composición, estructura y estado de conservación, así como inferir a partir de estas las condiciones ambientales imperantes en el área. La investigación se realizó entre enero y junio de 2009, en seis localidades ubicadas entre 12m y 17m de profundidad. Como unidad de muestreo se empleó un marco de 1m², el cual fue puesto en zigzag cada 2m sobre la superficie del arrecife de macizos. Se determinó, por localidad, la densidad de colonias y se infirieron los grados de severidad, constancia ambiental, tensión hidrodinámica y el Índice Comparativo de Contaminación. Se determinaron, además, los daños en la comunidad de octocorales. Se analizaron 752 colonias e identificaron 25 especies de octocorales. Eunicea flexuosa y Gorgonia ventalina fueron las especies más abundantes. La densidad fluctuó entre 3.58±1.84 colonias/m² y 7.58±2.16 colonias/ m² (densidad de baja a moderada tendiendo a baja. En la zona se infirió una tensión hidrodinámica entre baja y alta, con niveles de contaminación bajos y moderados, y un ambiente generalmente favorable y constante. Los daños de tipo mecánico fueron los más frecuentes, siendo G. ventalina la especie con más colonias dañadas. La comunidad de octocorales del hábitat de macizos y canales de la Reserva Ecológica Siboney-Juticí presentó un buen estado de conservación.Structure and injuries of octocoral communities (Octocorallia: Alcyonacea of Ecological Reserve Siboney-Juticí, Santiago de Cuba, Cuba. In the spur-and-groove reefs of the Ecological Reserve Siboney-Juticí (Southeast Cuba octocorals are one of the predominant components of the sessile fauna. Main objectives of the present paper are characterizing the composition, structure and conservation status of the octocoral communities and assessing on the

  18. Phenotypic plasticity and morphological integration in a marine modular invertebrate

    Directory of Open Access Journals (Sweden)

    Manrique Nelson

    2007-07-01

    Full Text Available Abstract Background Colonial invertebrates such as corals exhibit nested levels of modularity, imposing a challenge to the depiction of their morphological evolution. Comparisons among diverse Caribbean gorgonian corals suggest decoupling of evolution at the polyp vs. branch/internode levels. Thus, evolutionary change in polyp form or size (the colonial module sensu stricto does not imply a change in colony form (constructed of modular branches and other emergent features. This study examined the patterns of morphological integration at the intraspecific level. Pseudopterogorgia bipinnata (Verrill (Octocorallia: Gorgoniidae is a Caribbean shallow water gorgonian that can colonize most reef habitats (shallow/exposed vs. deep/protected; 1–45 m and shows great morphological variation. Results To characterize the genotype/environment relationship and phenotypic plasticity in P. bipinnata, two microsatellite loci, mitochondrial (MSH1 and nuclear (ITS DNA sequences, and (ITS2 DGGE banding patterns were initially compared among the populations present in the coral reefs of Belize (Carrie Bow Cay, Panama (Bocas del Toro, Colombia (Cartagena and the Bahamas (San Salvador. Despite the large and discrete differentiation of morphotypes, there was no concordant genetic variation (DGGE banding patterns in the ITS2 genotypes from Belize, Panama and Colombia. ITS1–5.8S-ITS2 phylogenetic analysis afforded evidence for considering the species P. kallos (Bielschowsky as the shallow-most morphotype of P. bipinnata from exposed environments. The population from Carrie Bow Cay, Belize (1–45 m was examined to determine the phenotypic integration of modular features such as branch thickness, polyp aperture, inter-polyp distance, internode length and branch length. Third-order partial correlation coefficients suggested significant integration between polypar and colonial traits. Some features did not change at all despite 10-fold differences in other integrated

  19. Temporal variability in epifaunal assemblages associated with temperate gorgonian gardens

    KAUST Repository

    Dias, I.M.; Curdia, Joao; Cunha, M.R.; Santos, M.N.; Carvalho, Susana

    2015-01-01

    The present study is one of the few that investigate the temporal variability of epifaunal assemblages associated with coral species, particularly the octocorals Eunicella gazella and Leptogorgia lusitanica in south Portugal. The results suggest time rather than colony size as a primary driver of the ecological patterns of these assemblages, which were dominated by amphipods, molluscs and polychaetes. Temporal variability was linked to changes in environmental parameters, namely temperature, chlorophyll a and particulate organic carbon. Hence, temporal variability must be taken into account for the design of future biodiversity assessment studies, as different patterns may be observed depending on the sampling time. Associated epifaunal assemblages were consistently dominated by resident species (i.e. species present in all sampling periods) and a peak of rare species was observed in the transition from spring to summer following the increase of seawater temperature. Turnover was particularly high in the transition between the spring and summer periods. In both hosts, turnover was higher in the small sized colonies, which generally harboured less diverse and less abundant assemblages which also differed from those inhabiting larger size colonies. The high levels of diversity associated with gorgonian colonies highlights the need for the conservation of this priority habitat.

  20. Excess seawater nutrients, enlarged algal symbiont densities and bleaching sensitive reef locations: 1. Identifying thresholds of concern for the Great Barrier Reef, Australia.

    Science.gov (United States)

    Wooldridge, Scott A

    2016-05-23

    Here, I contribute new insight into why excess seawater nutrients are an increasingly identified feature at reef locations that have low resistance to thermal stress. Specifically, I link this unfavourable synergism to the development of enlarged (suboptimal) zooxanthellae densities that paradoxically limit the capacity of the host coral to build tissue energy reserves needed to combat periods of stress. I explain how both theoretical predictions and field observations support the existence of species-specific 'optimal' zooxanthellae densities ~1.0-3.0×10 6 cellscm- 2 . For the central Great Barrier Reef (GBR), excess seawater nutrients that permit enlarged zooxanthellae densities beyond this optimum range are linked with seawater chlorophyll a>0.45μg·L -1 ; a eutrophication threshold previously shown to correlate with a significant loss in species for hard corals and phototrophic octocorals on the central GBR, and herein shown to correlate with enhanced bleaching sensitivity during the 1998 and 2002 mass bleaching events. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Characteristics of the mesophotic megabenthic assemblages of the vercelli seamount (north tyrrhenian sea.

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    Marzia Bo

    2011-02-01

    Full Text Available The biodiversity of the megabenthic assemblages of the mesophotic zone of a Tyrrhenian seamount (Vercelli Seamount is described using Remotely Operated Vehicle (ROV video imaging from 100 m depth to the top of the mount around 61 m depth. This pinnacle hosts a rich coralligenous community characterized by three different assemblages: (i the top shows a dense covering of the kelp Laminaria rodriguezii; (ii the southern side biocoenosis is mainly dominated by the octocorals Paramuricea clavata and Eunicella cavolinii; while (iii the northern side of the seamount assemblage is colonized by active filter-feeding organisms such as sponges (sometimes covering 100% of the surface with numerous colonies of the ascidian Diazona violacea, and the polychaete Sabella pavonina. This study highlights, also for a Mediterranean seamount, the potential role of an isolated rocky peak penetrating the euphotic zone, to work as an aggregating structure, hosting abundant benthic communities dominated by suspension feeders, whose distribution may vary in accordance to the geomorphology of the area and the different local hydrodynamic conditions.

  2. Vertical water mass structure in the North Atlantic influences the bathymetric distribution of species in the deep-sea coral genus Paramuricea

    Science.gov (United States)

    Radice, Veronica Z.; Quattrini, Andrea M.; Wareham, Vonda E.; Edinger, Evan N.; Cordes, Erik E.

    2016-10-01

    Deep-sea corals are the structural foundation of their ecosystems along continental margins worldwide, yet the factors driving their broad distribution are poorly understood. Environmental factors, especially depth-related variables including water mass properties, are thought to considerably affect the realized distribution of deep-sea corals. These factors are governed by local and regional oceanographic conditions that directly influence the dispersal of larvae, and therefore affect the ultimate distribution of adult corals. We used molecular barcoding of mitochondrial and nuclear sequences to identify species of octocorals in the genus Paramuricea collected from the Labrador Sea to the Grand Banks of Newfoundland, Canada at depths of 150-1500 m. The results of this study revealed overlapping bathymetric distributions of the Paramuricea species present off the eastern Canadian coast, including the presence of a few cryptic species previously designated as Paramuricea placomus. The distribution of Paramuricea species in the western North Atlantic differs from the Gulf of Mexico, where five Paramuricea species exhibit strong segregation by depth. The different patterns of Paramuricea species in these contrasting biogeographic regions provide insight into how water mass structure may shape species distribution. Investigating Paramuricea prevalence and distribution in conjunction with oceanographic conditions can help demonstrate the factors that generate and maintain deep-sea biodiversity.

  3. Severity of the 1998 and 2005 bleaching events in Venezuela, southern Caribbean

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    Sebastián Rodríguez

    2010-10-01

    Full Text Available This study describes the severity of the 2005 bleaching event at 15 reef sites across Venezuela and compares the 1998 and 2005 bleaching events at one of them. During August and September 2005, bleached corals were first observed on oceanic reefs rather than coastal reefs, affecting 1 to 4% of coral colonies in the community (3 reef sites, n=736 colonies. At that time, however, no bleached corals were recorded along the eastern coast of Venezuela, an area of seasonal upwelling (3 reefs, n=181 colonies. On coastal reefs, bleaching started in October but highest levels were reached in November 2005 and January 2006, when 16% of corals were affected among a wide range of taxa (e.g. scleractinians, octocorals, Millepora and zoanthids. In the Acropora habitats of Los Roques (an oceanic reef, no bleached was recorded in 2005 (four sites, n=643 colonies. At Cayo Sombrero, a coastal reef site, bleaching was less severe in 1998 than in 2005 (9% of the coral colonies involving 2 species vs. 26% involving 23 species, respectively. Our results indicate that bleaching was more severe in 2005 than in 1998 on Venezuelan reefs; however, no mass mortality was observed in either of these two events. Rev. Biol. Trop. 58 (Suppl. 3: 189-196. Epub 2010 October 01.

  4. Life in the colonies: learning the alien ways of colonial organisms.

    Science.gov (United States)

    Winston, Judith E

    2010-12-01

    Who needs to go to outer space to study alien beings when the oceans of our own planet abound with bizarre and unknown creatures? Many of them belong to sessile clonal and colonial groups, including sponges, hydroids, corals, octocorals, ascidians, bryozoans, and some polychaetes. Their life histories, in many ways unlike our own, are a challenge for biologists. Studying their ecology, behavior, and taxonomy means trying to “think like a colony” to understand the factors important in their lives. Until the 1980s, most marine ecologists ignored these difficult modular organisms. Plant ecologists showed them ways to deal with the two levels of asexually produced modules and genetic individuals, leading to a surge in research on the ecology of clonal and colonial marine invertebrates. Bryozoans make excellent model colonial animals. Their life histories range from ephemeral to perennial. Aspects of their lives such as growth, reproduction, partial mortality due to predation or fouling, and the behavior of both autozooids and polymorphs can be studied at the level of the colony, as well as that of the individual module, in living colonies and over time.

  5. Secondary metabolites from marine microorganisms.

    Science.gov (United States)

    Kelecom, Alphonse

    2002-03-01

    After 40 years of intensive research, chemistry of marine natural products has become a mature field. Since 1995, there are signals of decreased interest in the search of new metabolites from traditional sources such as macroalgae and octocorals, and the number of annual reports on marine sponges stabilized. On the contrary, metabolites from microorganisms is a rapidly growing field, due, at least in part, to the suspicion that a number of metabolites obtained from algae and invertebrates may be produced by associated microorganisms. Studies are concerned with bacteria and fungi, isolated from seawater, sediments, algae, fish and mainly from marine invertebrates such as sponges, mollusks, tunicates, coelenterates and crustaceans. Although it is still to early to define tendencies, it may be stated that the metabolites from microorganisms are in most cases quite different from those produced by the invertebrate hosts. Nitrogenated metabolites predominate over acetate derivatives, and terpenes are uncommon. Among the latter, sesquiterpenes, diterpenes and carotenes have been isolated; among nitrogenated metabolites, amides, cyclic peptides and indole alkaloids predominate.

  6. Secondary metabolites from marine microorganisms

    Directory of Open Access Journals (Sweden)

    KELECOM ALPHONSE

    2002-01-01

    Full Text Available After 40 years of intensive research, chemistry of marine natural products has become a mature field. Since 1995, there are signals of decreased interest in the search of new metabolites from traditional sources such as macroalgae and octocorals, and the number of annual reports on marine sponges stabilized. On the contrary, metabolites from microorganisms is a rapidly growing field, due, at least in part, to the suspicion that a number of metabolites obtained from algae and invertebrates may be produced by associated microorganisms. Studies are concerned with bacteria and fungi, isolated from seawater, sediments, algae, fish and mainly from marine invertebrates such as sponges, mollusks, tunicates, coelenterates and crustaceans. Although it is still to early to define tendencies, it may be stated that the metabolites from microorganisms are in most cases quite different from those produced by the invertebrate hosts. Nitrogenated metabolites predominate over acetate derivatives, and terpenes are uncommon. Among the latter, sesquiterpenes, diterpenes and carotenes have been isolated; among nitrogenated metabolites, amides, cyclic peptides and indole alkaloids predominate.

  7. Comparative mitogenomics, phylogeny and evolutionary history of Leptogorgia (Gorgoniidae).

    Science.gov (United States)

    Poliseno, Angelo; Feregrino, Christian; Sartoretto, Stéphane; Aurelle, Didier; Wörheide, Gert; McFadden, Catherine S; Vargas, Sergio

    2017-10-01

    Molecular analyses of the ecologically important gorgonian octocoral genus Leptogorgia are scant and mostly deal with few species from restricted geographical regions. Here we explore the phylogenetic relationships and the evolutionary history of Leptogorgia using the complete mitochondrial genomes of six Leptogorgia species from different localities in the Atlantic, Mediterranean and eastern Pacific as well as four other genera of Gorgoniidae and Plexauridae. Our mitogenomic analyses showed high inter-specific diversity, variable nucleotide substitution rates and, for some species, novel genomic features such as ORFs of unknown function. The phylogenetic analyses using complete mitogenomes and an extended mtMutS dataset recovered Leptogorgia as polyphyletic, and the species considered in the analyses were split into two defined groups corresponding to different geographic regions, namely the eastern Pacific and the Atlantic-Mediterranean. Our phylogenetic analysis based on mtMutS also showed a clear separation between the eastern Atlantic and South African Leptogorgia, suggesting the need of a taxonomic revision for these forms. A time-calibrated phylogeny showed that the separation of eastern Pacific and western Atlantic species started ca. 20Mya and suggested a recent divergence for eastern Pacific species and for L. sarmentosa-L. capverdensis. Our results also revealed high inter-specific diversity among eastern Atlantic and South African species, highlighting a potential role of the geographical diversification processes and geological events occurring during the last 30Ma in the Atlantic on the evolutionary history of these organisms. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Autecology of a symbiont-containing temperate soft coral Capnella gaboensis

    Energy Technology Data Exchange (ETDEWEB)

    Farrant, P.A.

    1985-01-01

    Capnella gaboensis Verseveldt is the most abundant and widely distributed octocoral growing in temperate Australian waters. This study of the autecology of C. gaboensis pays specific attention to its reproduction growth, population dynamics nutrition. Several populations of Capnella gaboensis were studied in the Sydney area. Colonies in the field populations were mapped and measured at regular intervals for growth and population data. The species is relatively long-lived, and large colonies are likely to be about 20 years of age. Following damage by predation or other causes, the larger colonies are able to heal rapidly. Reproduction and development of Capnella gaboensis was studied by microscopic examination of colony branches collected at regular intervals from colonies in the mapped populations. C. gaboensis is dioecious. Recruitment into Capnella gaboensis populations is mainly by larval production, rather than by asexual means. Only a very low percentage of larvae survive and settle. The survival of recruits is also low, and mortality declines as the colonies grow larger. Nutrition of Capnella gaboensis was investigated by /sup 14/C fixation and oxygen exchange methods in the laboratory. Although the numbers of zooxanthellae and chlorophyll content of C. gaboensis do not vary seasonally, photosynthesis by the zooxanthellae does. Photosynthesis of C. gaboensis appears to be adapted to the temperate habitat in which the species lives. Photosynthetic products, translocated form the zooxanthellae to the animal tissues, provided an important source of nutrition for C. gaboensis.

  9. Temporal variability in epifaunal assemblages associated with temperate gorgonian gardens

    KAUST Repository

    Dias, I.M.

    2015-10-19

    The present study is one of the few that investigate the temporal variability of epifaunal assemblages associated with coral species, particularly the octocorals Eunicella gazella and Leptogorgia lusitanica in south Portugal. The results suggest time rather than colony size as a primary driver of the ecological patterns of these assemblages, which were dominated by amphipods, molluscs and polychaetes. Temporal variability was linked to changes in environmental parameters, namely temperature, chlorophyll a and particulate organic carbon. Hence, temporal variability must be taken into account for the design of future biodiversity assessment studies, as different patterns may be observed depending on the sampling time. Associated epifaunal assemblages were consistently dominated by resident species (i.e. species present in all sampling periods) and a peak of rare species was observed in the transition from spring to summer following the increase of seawater temperature. Turnover was particularly high in the transition between the spring and summer periods. In both hosts, turnover was higher in the small sized colonies, which generally harboured less diverse and less abundant assemblages which also differed from those inhabiting larger size colonies. The high levels of diversity associated with gorgonian colonies highlights the need for the conservation of this priority habitat.

  10. Investigation of trophic ecology in Newfoundland cold-water deep-sea corals using lipid class and fatty acid analyses

    Science.gov (United States)

    Salvo, Flora; Hamoutene, Dounia; Hayes, Vonda E. Wareham; Edinger, Evan N.; Parrish, Christopher C.

    2018-03-01

    The trophic behavior of some deep-sea Newfoundland cold-water corals was explored using fatty acid (FA) and lipid profiles. No significant effect of geographic location and/or depth was identified in lipid or FA composition. However, differences were detected between and within taxon groups in hexa- or octocoral subclasses. Phospholipids constituted the main lipid class in all groups except black-thorny corals which had less structural lipids likely due to their morphology (stiff axes) and slower growth rates. Within each subclass, major differences in the identity of dominant FAs were detected at the order level, whereas differences between species and taxon groups of the same order were mainly driven by a variation in proportions of the dominant FA. Soft corals and gorgonians (Order Alcyonacea) were close in composition and are likely relying on phytodetritus resulting from algae, macrophytes and/or foraminifera, while sea pens (Order Pennatulacea) seem to consume more diatoms and/or herbivorous zooplankton with the exception of Pennatula sp. In the hexacoral subclass, black-thorny corals ( Stauropathes arctica) differed significantly from the stony-cup corals ( Flabellum alabastrum); S. arctica was seemingly more carnivorous (zooplankton markers) than F. alabastrum, which appears omnivorous (phyto- and zooplankton markers). Our results suggest that deep-sea corals are not as opportunistic as expected but have some selective feeding associated with taxonomy.

  11. Symbiodinium diversity in the soft coral Heteroxenia sp. and its nudibranch predator Phyllodesmium lizardensis

    Science.gov (United States)

    FitzPatrick, S. K.; Liberatore, K. L.; Garcia, J. R.; Burghardt, I.; Colman, D. R.; Moquin, S. A.; Takacs-Vesbach, C. D.; Shepherd, U. L.

    2012-09-01

    We examined the diversity of the photosynthetic dinoflagellate, Symbiodinium, over a 2-year period in two invertebrates from Australia's Northern Great Barrier Reef: the nudibranch Phyllodesmium lizardensis and an octocoral of the genus Heteroxenia. In years one and two, we used denaturing gradient gel electrophoresis with internal transcribed spacer 2 (ITS2) region amplicons and identified two nearly identical genotypes of clade C (C64 and a variant) in all samples of each species. We examined the secondary structure of both sequences and found that each had predicted ∆G values within the range of stable free energy values for Symbiodinium ITS2 sequences. In year two, we also used real-time quantitative polymerase chain reaction assays (qPCR) with clade-specific internal transcribed spacer 1 primers to determine whether there were cryptic clades (A, B, and/or D) associated with either host in addition to clade C. qPCR revealed that clades B, C, and D were present in all animals of both species and that all but two nudibranch samples also harbored clade A. These findings suggest that there may be more flexibility in this host/symbiont interaction than has previously been assumed.

  12. Ecological adaptations and commensal evolution of the Polynoidae (Polychaeta) in the Southwest Indian Ocean Ridge: A phylogenetic approach

    Science.gov (United States)

    Serpetti, Natalia; Taylor, M. L.; Brennan, D.; Green, D. H.; Rogers, A. D.; Paterson, G. L. J.; Narayanaswamy, B. E.

    2017-03-01

    The polychaete family polynoid is very large and includes a high diversity of behaviours, including numerous examples of commensal species. The comparison between free-living and commensal behaviours and the evolution of the relationships between commensal species and their hosts are valuable case studies of ecological adaptations. Deep-sea species of Polynoidae were sampled at four seamounts in the Southwest Indian Ridge and twenty specimens from seven species were selected to be analysed. Among them, there were free-living species, living within the three-dimensional framework of cold-water coral reefs, on coral rubble and on mobile sediments, and commensal species, associated with octocorals, hydrocorals (stylasterids), antipatharians and echinoderms (holothurian and ophiuroids). We analysed two mitochondrial (COI, 16S) and two nuclear (18S, 28S) ribosomal genetic markers and their combined sequences were compared with other Genbank sequences to assess the taxonomic relationships within the species under study, and the potential role of hosts in speciation processes. Most basal species of the sub-family Polynoinae are obligate symbionts showing specific morphological adaptations. Obligate and facultative commensal species and free-living species have evolved a number of times, although, according to our results, the obligate coral commensal species appear to be monophyletic.

  13. Severity of the 1998 and 2005 bleaching events in Venezuela, southern Caribbean.

    Science.gov (United States)

    Rodríguez, Sebastián; Cróquer, Aldo; Bone, David; Bastidas, Carolina

    2010-10-01

    This study describes the severity of the 2005 bleaching event at 15 reef sites across Venezuela and compares the 1998 and 2005 bleaching events at one of them. During August and September 2005, bleached corals were first observed on oceanic reefs rather than coastal reefs, affecting 1 to 4% of coral colonies in the community (3 reef sites, n = 736 colonies). At that time, however, no bleached corals were recorded along the eastern coast of Venezuela, an area of seasonal upwelling (3 reefs, n = 181 colonies). On coastal reefs, bleaching started in October but highest levels were reached in November 2005 and January 2006, when 16% of corals were affected among a wide range of taxa (e.g. scleractinians, octocorals, Millepora and zoanthids). In the Acropora habitats of Los Roques (an oceanic reef),no bleached was recorded in 2005 (four sites,n = 643 colonies). At Cayo Sombrero, a coastal reef site, bleaching was less severe in 1998 than in 2005 (9% of the coral colonies involving 2 species vs. 26% involving 23 species, respectively). Our results indicate that bleaching was more severe in 2005 than in 1998 on Venezuelan reefs; however, no mass mortality was observed in either of these two events.

  14. The synthesis of mycosporine-like amino acids (MAAs) by cultured, symbiotic dinoflagellates.

    Science.gov (United States)

    T Banaszak1 A; LaJeunesse; Trench

    2000-06-28

    We tested the hypothesis that there is a relation between phylotypes (phylogenetic types, as determined by restriction fragment length polymorphism (RFLP) and partial sequence analysis of the small subunit ribosomal RNA gene (SSUrDNA)) and the synthesis of mycosporine-like amino acids (MAAs) by symbiotic dinoflagellates under the influence of ultraviolet radiation (UV-B/A) and photosynthetically active radiation (PAR). We exposed 27 isolates of symbiotic dinoflagellates simultaneously to UV-B/A and PAR, and subsequently determined the MAAs present in cell extracts and in the media. The algae used included 24 isolates of Symbiodinium spp. originating from jellyfishes, sea anemones, zoanthids, scleractinians, octocorals, and bivalves, and three others in the genera Gymnodinium, Gloeodinium and Amphidinium from a jellyfish, an hydrocoral and a flatworm, respectively. In this study, all of the phylotype A Symbiodinium spp. synthesized up to three identified MAAs. None of the 11 cultured phylotypes B and C Symbiodinium spp. synthesized MAAs. The three non-Symbiodinium symbionts also synthesized up to three MAAs. The results support a conclusion that phylotype A Symbiodinium spp. have a high predilection for the synthesis of MAAs, while phylotypes B and C do not. Synthesis of MAAs by symbiotic dinoflagellates in culture does not appear to relate directly to depths or to the UV exposure regimes from which the consortia were collected.

  15. Of reef fishes, overfishing and in situ observations of fish traps in St. John, U.S. Virgin Islands

    Science.gov (United States)

    Garrison, Virginia H.; Rogers, Caroline S.; Beets, J.

    1998-01-01

    Fishing with a variety of methods and gears, including traps, is allowed within the waters of Virgin Islands National Park (St. 10hn, U.S. Virgin Islands). Randall's 1 9 6 1 observation of the effects of overushing in nearshore waters off Sto John has been followed by three and a half decades of reports documenting the declining reef fish catch in the Virgin Islands and much of the Caribbean. To assess the state of the trap fishery in St. John waters, traps set by fishers were visually censused in situ in 1992, 1993 and 1994 both inside and outside park waters. Fifty-nine species of fishes representing 23 families and 1340 individuals were identified from 285 traps set in five habitat types (coral reef, octocoral hard-bottom, seagrass beds, algal plains and non-living substrate). The greatest number of observed traps were in algal plain (31%) and gorgonian habitat (27%), pointing to greater exploitation of deeper, non­ coral habitats. Coral habitat accounted for the most species trapped (41), whereas the mean number of fishes per trap was highest in algal plain (5.7, se=0.6). Six species made up 51% of all fish observed in traps. The Acanthuridae was the most abundant family. Species composition and number of fishes per trap were similar inside and outside park waters. Scarids and serranids were more frequently observed in traps inside the park. Between 1992 and 1994. patterns in the data emerged: smaller numbers of fish per trap; shifts to smaller size classes; fewer serranids, lutjanids, sparids, and balistids, and all feeding guilds except herbivores per trap; more acanthurids per trap. Compared with other trap data from the Virgin Islands and the Caribbean - Florida region, the mean number of fish and biomass per St. John trap are low, serranid numbers are low, and acanthurid and herbivore numbers are high. The reef-associated fishes of St. John appear to be overexploited.

  16. Coral-Associated Bacterial Diversity is Conserved Across Two Deep-Sea Anthothela Species

    Directory of Open Access Journals (Sweden)

    Stephanie Nichole Lawler

    2016-04-01

    Full Text Available Cold-water corals, similar to tropical corals, contain diverse and complex microbial assemblages. These bacteria provide essential biological functions within coral holobionts, facilitating increased nutrient utilization and production of antimicrobial compounds. To date, few cold-water octocoral species have been analyzed to explore the diversity and abundance of their microbial associates. For this study, 23 samples of the family Anthothelidae were collected from Norfolk (n = 12 and Baltimore Canyons (n = 11 from the western Atlantic in August 2012 and May 2013. Genetic testing found that these samples comprised two Anthothela species (Anthothela grandiflora and Anthothela sp. and Alcyonium grandiflorum. DNA was extracted and sequenced with primers targeting the V4-V5 variable region of the 16S rRNA gene using 454 pyrosequencing with GS FLX Titanium chemistry. Results demonstrated that the coral host was the primary driver of bacterial community composition. Al. grandiflorum, dominated by Alteromonadales and Pirellulales had much higher species richness, and a distinct bacterial community compared to Anthothela samples. Anthothela species (A. grandiflora and Anthothela sp. had very similar bacterial communities, dominated by Oceanospirillales and Spirochaetes. Additional analysis of core-conserved bacteria at 90% sample coverage revealed genus level conservation across Anthothela samples. This core included unclassified Oceanospirillales, Kiloniellales, Campylobacterales, and genus Spirochaeta. Members of this core were previously recognized for their functional capabilities in nitrogen cycling and suggest the possibility of a nearly complete nitrogen cycle within Anthothela species. Overall, many of the bacterial associates identified in this study have the potential to contribute to the acquisition and cycling of nutrients within the coral holobiont.

  17. Is dimethylsulfoniopropionate (DMSP) produced by the symbionts or the host in an anemone-zooxanthella symbiosis?

    Science.gov (United States)

    van Alstyne, K. L.; Dominique, V. J.; Muller-Parker, G.

    2009-03-01

    Many groups of tropical cnidarians including scleractinian corals, octocorals, corallimorphs, and anemones contain the tertiary sulfonium compound dimethylsulfoniopropionate (DMSP). It is not known if the compound is synthesized by the animals, their microalgal symbionts, or derived through their diet. We determined the source of the DMSP in several species of tropical and temperate anemones using three approaches: (1) conducting comparative measurements of DMSP in aposymbiotic and zooxanthellate anemones of three species that harbor zooxanthellae, and similar measurements in one species that can harbor both zooxanthellae and zoochlorellae, (2) manipulating the presence or absence of zooxanthellae by inoculating juvenile aposymbiotic anemones ( Aiptasia pallida) with their symbiont, Symbiodinium bermudense, and (3) manipulating the numbers of S. bermudense by growing aposymbiotic and zooxanthellate A. pallida in the light and the dark. DMSP was present in zooxanthellate anemones in concentrations of 3.4-15 μmol g-1 fresh mass (FM). In aposymbiotic Aiptasia spp. and Anthopleura elegantissima that lacked large numbers of zooxanthellae, concentrations ranged from being undetectable to 0.43 μmol g-1 FM. When aposymbiotic A. pallida were inoculated with zooxanthellae, concentrations of DMSP were an average of 4.24 μmol g-1 FM after 5 weeks; DMSP was undetectable in uninoculated control animals. Aposymbiotic anemones maintained in the light or the dark for 6 weeks contained no DMSP or zooxanthellae. Zooxanthellate anemones in the light contained five times as many zooxanthellae and approximately 7.5 times as much DMSP as zooxanthellate anemones maintained in the dark. Taken together, these data show that the zooxanthellae are the sole source of DMSP in A. pallida. The trends in DMSP concentrations in other species of zooxanthellate anemones suggest that this phenomenon is not limited to A. pallida but may be more generally true for other anemones or even other

  18. Climate change impacts on coral reefs: synergies with local effects, possibilities for acclimation, and management implications.

    Science.gov (United States)

    Ateweberhan, Mebrahtu; Feary, David A; Keshavmurthy, Shashank; Chen, Allen; Schleyer, Michael H; Sheppard, Charles R C

    2013-09-30

    Most reviews concerning the impact of climate change on coral reefs discuss independent effects of warming or ocean acidification. However, the interactions between these, and between these and direct local stressors are less well addressed. This review underlines that coral bleaching, acidification, and diseases are expected to interact synergistically, and will negatively influence survival, growth, reproduction, larval development, settlement, and post-settlement development of corals. Interactions with local stress factors such as pollution, sedimentation, and overfishing are further expected to compound effects of climate change. Reduced coral cover and species composition following coral bleaching events affect coral reef fish community structure, with variable outcomes depending on their habitat dependence and trophic specialisation. Ocean acidification itself impacts fish mainly indirectly through disruption of predation- and habitat-associated behavior changes. Zooxanthellate octocorals on reefs are often overlooked but are substantial occupiers of space; these also are highly susceptible to bleaching but because they tend to be more heterotrophic, climate change impacts mainly manifest in terms of changes in species composition and population structure. Non-calcifying macroalgae are expected to respond positively to ocean acidification and promote microbe-induced coral mortality via the release of dissolved compounds, thus intensifying phase-shifts from coral to macroalgal domination. Adaptation of corals to these consequences of CO2 rise through increased tolerance of corals and successful mutualistic associations between corals and zooxanthellae is likely to be insufficient to match the rate and frequency of the projected changes. Impacts are interactive and magnified, and because there is a limited capacity for corals to adapt to climate change, global targets of carbon emission reductions are insufficient for coral reefs, so lower targets should be

  19. Calcite Formation in Soft Coral Sclerites Is Determined by a Single Reactive Extracellular Protein*

    Science.gov (United States)

    Rahman, M. Azizur; Oomori, Tamotsu; Wörheide, Gert

    2011-01-01

    Calcium carbonate exists in two main forms, calcite and aragonite, in the skeletons of marine organisms. The primary mineralogy of marine carbonates has changed over the history of the earth depending on the magnesium/calcium ratio in seawater during the periods of the so-called “calcite and aragonite seas.” Organisms that prefer certain mineralogy appear to flourish when their preferred mineralogy is favored by seawater chemistry. However, this rule is not without exceptions. For example, some octocorals produce calcite despite living in an aragonite sea. Here, we address the unresolved question of how organisms such as soft corals are able to form calcitic skeletal elements in an aragonite sea. We show that an extracellular protein called ECMP-67 isolated from soft coral sclerites induces calcite formation in vitro even when the composition of the calcifying solution favors aragonite precipitation. Structural details of both the surface and the interior of single crystals generated upon interaction with ECMP-67 were analyzed with an apertureless-type near-field IR microscope with high spatial resolution. The results show that this protein is the main determining factor for driving the production of calcite instead of aragonite in the biocalcification process and that –OH, secondary structures (e.g. α-helices and amides), and other necessary chemical groups are distributed over the center of the calcite crystals. Using an atomic force microscope, we also explored how this extracellular protein significantly affects the molecular-scale kinetics of crystal formation. We anticipate that a more thorough investigation of the proteinaceous skeleton content of different calcite-producing marine organisms will reveal similar components that determine the mineralogy of the organisms. These findings have significant implications for future models of the crystal structure of calcite in nature. PMID:21768106

  20. Discovery of asphalt seeps in the deep Southwest Atlantic off Brazil

    Science.gov (United States)

    Fujikura, Katsunori; Yamanaka, Toshiro; Sumida, Paulo Y. G.; Bernardino, Angelo F.; Pereira, Olivia S.; Kanehara, Toshiyuki; Nagano, Yuriko; Nakayama, Cristina R.; Nobrega, Marcos; Pellizari, Vivian H.; Shigeno, Shuichi; Yoshida, Takao; Zhang, Jing; Kitazato, Hiroshi

    2017-12-01

    The discovery and description of cold seeps with deep-sea chemosynthetic communities in the Southwest Atlantic Ocean are still incomplete, despite the large proven oil and gas reserves off the coast of Brazil. In the southeastern Brazilian continental margin, where over 71% of the country's oil and gas production takes place, there are previous geological and qualitative biological evidence of seep biota associated with pockmarks on the upper slope of the Santos Basin. In order to further study seep ecosystems on the Brazilian margin, a deep-sea investigation named Iatá-Piúna cruise was conducted using the human-occupied vehicle Shinkai 6500 off Brazil's southeast continental margin. Asphalt seeps were discovered on the seafloor of the North São Paulo Plateau from depths of 2652-2752 m, representing only the third discovery of this type of seep worldwide, following those in the Gulf of Mexico and off Angola. Video and isotopic analyses indicated a number of megabenthic animals in the asphalt seeps in the North São Paulo Plateau and revealed typical deep-sea heterotrophic and photosynthesis-based fauna occupying hard substrates provided by the asphalt seep. There was no evidence of chemosynthesis-based megabenthic fauna such as vesicomyid clams, Bathymodiolus mussels, and siboglinid tube worms, or any sediment bacterial mats, gas seepage, and carbonate rock in/around the seeps. The benthic fauna was composed mainly of sponges (ca. 15 species), such as the hexactinellids Caulophacus sp., Poliopogon amadou, Saccocalyx pedunculatus, Farrea occa and cf. Chonelasma choanoides; besides typical deep-sea isidid octocorals, brisingid starfishes and galatheid crabs. The δ13C values of poriferan sponges suggested a heterotrophic and pelagic nutrition. Geochemical analyses of asphalt revealed a heavy biodegradation of hydrocarbon molecules, supported by the depletion of light n-alkanes and other labile compounds. This advanced asphalt biodegradation is the likely reason

  1. Trophic ecology of deep-sea Asteroidea (Echinodermata) from eastern Canada

    Science.gov (United States)

    Gale, Katie S. P.; Hamel, Jean-François; Mercier, Annie

    2013-10-01

    Asteroids (sea stars) can be important predators in benthic communities and are often present in ecologically important and vulnerable deep-sea coral and sponge habitats. However, explicit studies on the trophic ecology of deep-sea asteroids are rare. We investigated the diets of seven species of deep-sea asteroid from the bathyal zone of Newfoundland and Labrador, eastern Canada. A multifaceted approach including live animal observations, stomach content analysis, and stable isotope analysis revealed the asteroids to be either top predators of megafauna or secondary consumers (mud ingesters, infaunal predators, and suspension feeders). The stable isotope signatures of Ceramaster granularis, Hippasteria phrygiana, and Mediaster bairdi are characteristic of high-level predators, having δ15N values 4.4‰ (more than one trophic level) above Ctenodiscus crispatus, Leptychaster arcticus, Novodinia americana, and Zoroaster fulgens. We present strong evidence that corals and sponges are common food items for two of the predatory species, C. granularis and H. phrygiana. During laboratory feeding trials, live H. phrygiana fed on several species of soft coral and C. granularis fed on sponges. Stomach content analysis of wild-caught individuals revealed sclerites from sea pens (e.g. Pennatula sp.) in the stomachs of both asteroid species; H. phrygiana also contained sclerites from at least two other species of octocoral and siliceous sponge spicules were present in the stomachs of C. granularis. The stomach contents of the secondary consumers contained a range of invertebrate material. Leptychaster arcticus and Ctenodiscus crispatus feed infaunally on bulk sediment and molluscs, Zoroaster fulgens is a generalist infaunal predator, and the brisingid Novodinia americana is a specialist suspension feeder on benthopelagic crustaceans. This study provides a foundation for understanding the ecological roles of bathyal asteroids, and suggests that some species may have the

  2. Exploration of the Canyon-Incised Continental Margin of the Northeastern United States Reveals Dynamic Habitats and Diverse Communities.

    Directory of Open Access Journals (Sweden)

    Andrea M Quattrini

    Full Text Available The continental margin off the northeastern United States (NEUS contains numerous, topographically complex features that increase habitat heterogeneity across the region. However, the majority of these rugged features have never been surveyed, particularly using direct observations. During summer 2013, 31 Remotely-Operated Vehicle (ROV dives were conducted from 494 to 3271 m depth across a variety of seafloor features to document communities and to infer geological processes that produced such features. The ROV surveyed six broad-scale habitat features, consisting of shelf-breaching canyons, slope-sourced canyons, inter-canyon areas, open-slope/landslide-scar areas, hydrocarbon seeps, and Mytilus Seamount. Four previously unknown chemosynthetic communities dominated by Bathymodiolus mussels were documented. Seafloor methane hydrate was observed at two seep sites. Multivariate analyses indicated that depth and broad-scale habitat significantly influenced megafaunal coral (58 taxa, demersal fish (69 taxa, and decapod crustacean (34 taxa assemblages. Species richness of fishes and crustaceans significantly declined with depth, while there was no relationship between coral richness and depth. Turnover in assemblage structure occurred on the middle to lower slope at the approximate boundaries of water masses found previously in the region. Coral species richness was also an important variable explaining variation in fish and crustacean assemblages. Coral diversity may serve as an indicator of habitat suitability and variation in available niche diversity for these taxonomic groups. Our surveys added 24 putative coral species and three fishes to the known regional fauna, including the black coral Telopathes magna, the octocoral Metallogorgia melanotrichos and the fishes Gaidropsarus argentatus, Guttigadus latifrons, and Lepidion guentheri. Marine litter was observed on 81% of the dives, with at least 12 coral colonies entangled in debris. While

  3. Energetic constraints, size gradients, and size limits in benthic marine invertebrates.

    Science.gov (United States)

    Sebens, Kenneth P

    2002-08-01

    Populations of marine benthic organisms occupy habitats with a range of physical and biological characteristics. In the intertidal zone, energetic costs increase with temperature and aerial exposure, and prey intake increases with immersion time, generating size gradients with small individuals often found at upper limits of distribution. Wave action can have similar effects, limiting feeding time or success, although certain species benefit from wave dislodgment of their prey; this also results in gradients of size and morphology. The difference between energy intake and metabolic (and/or behavioral) costs can be used to determine an energetic optimal size for individuals in such populations. Comparisons of the energetic optimal size to the maximum predicted size based on mechanical constraints, and the ensuing mortality schedule, provides a mechanism to study and explain organism size gradients in intertidal and subtidal habitats. For species where the energetic optimal size is well below the maximum size that could persist under a certain set of wave/flow conditions, it is probable that energetic constraints dominate. When the opposite is true, populations of small individuals can dominate habitats with strong dislodgment or damage probability. When the maximum size of individuals is far below either energetic optima or mechanical limits, other sources of mortality (e.g., predation) may favor energy allocation to early reproduction rather than to continued growth. Predictions based on optimal size models have been tested for a variety of intertidal and subtidal invertebrates including sea anemones, corals, and octocorals. This paper provides a review of the optimal size concept, and employs a combination of the optimal energetic size model and life history modeling approach to explore energy allocation to growth or reproduction as the optimal size is approached.

  4. Benthic megafaunal community structure of cobalt-rich manganese crusts on Necker Ridge

    Science.gov (United States)

    Morgan, Nicole B.; Cairns, Stephen; Reiswig, Henry; Baco, Amy R.

    2015-10-01

    In the North Pacific Ocean, the seamounts of the Hawaiian Archipelago and the Mid-Pacific Mountains are connected by Necker Ridge, a 600 km-long feature spanning a depth range of 1400-4000 m. The Necker Ridge is a part of a large area of the central and western Pacific under consideration for cobalt-rich manganese crust mining. We describe the fauna and community structure of the previously unsampled Necker Ridge based on explorations with the submersible Pisces IV. On five pinnacles and a portion of the Ridge ranging from 1400 to 2000 m deep, 27 transects were recorded using HD video, and voucher specimens were collected to aid in species identification. The video was analyzed to identify and count the megafauna found on each transect and to characterize the substrate. Diversity increased from south to north along the feature. There was a significant difference in community structure between southern and northern pinnacles, with southern pinnacles dominated by crinoids of the Family Charitometridae and northern pinnacles dominated by octocorals, especially the Families Isididae and Chrysogorgiidae. DistLM demonstrated a correlation between community structure on the pinnacles and at least six environmental variables, including latitude, sediment cover, and oxygen concentration, but not including depth. The discontinuous and patchy nature of these distinct megafaunal communities highlights growing evidence that cobalt-rich seamounts are highly heterogeneous habitats, and that managing seamounts may require more complex regulations than treating them as a single ecological unit. These results suggest that extensive community analysis should occur at a given site to determine management priority areas, prior to consideration of that site for exploitation of natural resources.

  5. Phenotypic plasticity or speciation? A case from a clonal marine organism

    Directory of Open Access Journals (Sweden)

    Yoshioka Paul M

    2008-02-01

    Full Text Available Abstract Background Clonal marine organisms exhibit high levels of morphological variation. Morphological differences may be a response to environmental factors but also they can be attributed to accumulated genetic differences due to disruption of gene flow among populations. In this study, we examined the extensive morphological variation (of 14 characters in natural populations observed in the gorgonian Eunicea flexuosa, a widely distributed Caribbean octocoral. Eco-phenotypic and genetic effects were evaluated by reciprocal transplants of colonies inhabiting opposite ends of the depth gradient and analysis of population genetics of mitochondrial and nuclear genes, respectively. Results Significant differences (P 17 m. A discriminant function analysis based on a priori univariate and multivariate analyses (which separated the colonies in morphotypes correctly classified 93% of the colonies for each environment. Light, water motion and sediment transport might influence the distribution of the two morphotypes. Reaction norms of morphological characters of colonies reciprocally transplanted showed gradual significant changes through the 15 months of transplantation. Sclerites of shallow water colonies became larger when transplanted to deeper environments and vice versa, but neither of the two transplanted groups overlapped with the residents' morphology. Genetic analysis of mitochondrial and nuclear genes suggested that such discrete morphology and non-overlapping phenotypic plasticity is correlated with the presence of two independent evolutionary lineages. The distribution of the lineages is non-random and may be related to adaptational responses of each lineage to the environmental demands of each habitat. Conclusion The extensive distribution and ample morphological variation of Eunicea flexuosa corresponds to two distinct genetic lineages with narrower distributions and more rigid phenotypic plasticity than the original description. The

  6. Characterization of Methane-Seep Communities in a Deep-Sea Area Designated for Oil and Natural Gas Exploitation Off Trinidad and Tobago

    Directory of Open Access Journals (Sweden)

    Diva J. Amon

    2017-10-01

    Full Text Available Exploration of the deep ocean (>200 m is taking on added importance as human development encroaches. Despite increasing oil and natural gas exploration and exploitation, the deep ocean of Trinidad and Tobago is almost entirely unknown. The only scientific team to image the deep seafloor within the Trinidad and Tobago Exclusive Economic Zone was from IFREMER in the 1980s. That exploration led to the discovery of the El Pilar methane seeps and associated chemosynthetic communities on the accretionary prism to the east of Trinidad and Tobago. In 2014, the E/V Nautilus, in collaboration with local scientists, visited two previously sampled as well as two unexplored areas of the El Pilar site between 998 and 1,629 m depth using remotely operated vehicles. Eighty-three megafaunal morphospecies from extensive chemosynthetic communities surrounding active methane seepage were observed at four sites. These communities were dominated by megafaunal invertebrates including mussels (Bathymodiolus childressi, shrimp (Alvinocaris cf. muricola, Lamellibrachia sp. 2 tubeworms, and Pachycara caribbaeum. Adjacent to areas of active seepage was an ecotone of suspension feeders including Haplosclerida sponges, stylasterids and Neovermilia serpulids on authigenic carbonates. Beyond this were large Bathymodiolus shell middens. Finally there was either a zone of sparse octocorals and other non-chemosynthetic species likely benefiting from the carbonate substratum and enriched production within the seep habitat, or sedimented inactive areas. This paper highlights these ecologically significant areas and increases the knowledge of the biodiversity of the Trinidad and Tobago deep ocean. Because methane seepage and chemosynthetic communities are related to the presence of extractable oil and gas resources, development of best practices for the conservation of biodiversity in Trinidad and Tobago waters within the context of energy extraction is critical. Potential impacts

  7. Large-scale coral recruitment patterns on Mona Island, Puerto Rico: evidence of a transitional community trajectory after massive coral bleaching and mortality

    Directory of Open Access Journals (Sweden)

    Edwin A. Hernández-Delgado

    2014-09-01

    Full Text Available Coral reefs have largely declined across the northeastern Caribbean following the 2005 massive bleaching event. Climate change-related sea surface warming and coral disease outbreaks of a white plague-like syndrome and of yellow band disease (YBD have caused significant coral decline affecting massive reef building species (i.e., Orbicella annularis species complex which show no apparent signs of recovery through larval sexual recruitment. We addressed coral recruit densities across three spur and groove reef locations along the western shelf of remote Mona Island, Puerto Rico: Punta Capitán (PCA, Pasa de Las Carmelitas (PLC, and Las Carmelitas-South (LCS. Data were collected during November 2012 along 93 haphazard transects across three depth zones (<5m, 5-10m, 10-15m. A total of 32 coral species (9 octocorals, 1 hydrocoral, 22 scleractinians were documented among the recruit community. Communities had low densities and dominance by short-lived brooder species seven years after the 2005 event. Mean coral recruit density ranged from 1.2 to 10.5/m2 at PCA, 6.3 to 7.2/m² at LCS, 4.5 to 9.5/m² at PLC. Differences in coral recruit community structure can be attributed to slight variation in percent macroalgal cover and composition as study sites had nearly similar benthic spatial heterogeneity. Dominance by ephemeral coral species was widespread. Recovery of largely declining massive reef-building species such as the O. annularis species complex was limited or non-existent. The lack of recovery could be the combined result of several mechanisms involving climate change, YBD disease, macroalgae, fishing, urchins and Mona Island’s reefs limited connectivity to other reef systems. There is also for rehabilitation of fish trophic structure, with emphasis in recovering herbivore guilds and depleted populations of D. antillarum. Failing to recognize the importance of ecosystem-based management and resilience rehabilitation may deem remote coral reefs

  8. Reprint of - Deep-sea coral and hardbottom habitats on the west Florida slope, eastern Gulf of Mexico

    Science.gov (United States)

    Ross, Steve W.; Rhode, Mike; Brooke, Sandra

    2017-09-01

    Until recently, benthic habitats dominated by deep-sea corals (DSC) appeared to be less extensive on the slope of the Gulf of Mexico (GOM) than in the northeast Atlantic Ocean or off the southeastern US. There are relatively few bioherms (i.e., coral-built mounds) in the northern GOM, and most DSCs are attached to existing hard substrata (e.g., authigenically formed carbonate). The primary structure-forming, DSC in the GOM is Lophelia pertusa, but structure is also provided by other living and dead scleractinians, antipatharians (black corals), octocorals (gorgonians, soft corals), hydrocorals and sponges, as well as abundant rocky substrata. The best development of DSCs in the GOM was previously documented within Viosca Knoll oil and gas lease blocks 826 and 862/906 (north-central GOM) and on the Campeche Bank (southern GOM in Mexican waters). This paper documents extensive deep reef ecosystems composed of DSC and rocky hard-bottom recently surveyed on the West Florida Slope (WFS, eastern GOM) during six research cruises (2008-2012). Using multibeam sonar, CTD casts, and video from underwater vehicles, we describe the physical and oceanographic characteristics of these deep reefs and provide size or area estimates of deep coral and hardground habitats. The multibeam sonar analyses revealed hundreds of mounds and ridges, some of which were subsequently surveyed using underwater vehicles. Mounds and ridges in <525 m depths were usually capped with living coral colonies, dominated by L. pertusa. An extensive rocky scarp, running roughly north-south for at least 229 km, supported lower abundances of scleractinian corals than the mounds and ridges, despite an abundance of settlement substrata. Areal comparisons suggested that the WFS may exceed other parts of the GOM slope in extent of living deep coral coverage and other deep-reef habitat (dead coral and rock). The complex WFS region warrants additional studies to better understand the influences of oceanography and

  9. Online 3D EPID-based dose verification: Proof of concept

    Energy Technology Data Exchange (ETDEWEB)

    Spreeuw, Hanno; Rozendaal, Roel, E-mail: r.rozendaal@nki.nl; Olaciregui-Ruiz, Igor; González, Patrick; Mans, Anton; Mijnheer, Ben [Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam 1066 CX (Netherlands); Herk, Marcel van [University of Manchester, Manchester Academic Health Science Centre, The Christie NHS Foundation Trust, Manchester M20 4BX (United Kingdom)

    2016-07-15

    , including dose verification, took 266 ± 11 ms on a dual octocore Intel Xeon E5-2630 CPU running at 2.40 GHz. The introduced delivery errors were detected after 5–10 s irradiation time. Conclusions: A prototype online 3D dose verification tool using portal imaging has been developed and successfully tested for two different kinds of gross delivery errors. Thus, online 3D dose verification has been technologically achieved.

  10. Satellite Derived Seafloor Bathymetry and Habitat Mapping on a Shallow Carbonate Platform: Campeche Bank, México.

    Science.gov (United States)

    Garza-Perez, J. R.; Rankey, E. C.; Rodriguez-Vázquez, R. A.; Naranjo-Garcia, M. J.

    2017-12-01

    Extensive and consistent high-resolution seafloor mapping is a difficult task involving important financial resources, intensive field work and careful planning; thus there is a paucity of this type of mapping products both in spatial distribution and through time. Remote sensed imagery has supported continuous mapping efforts elsewhere, but extensive seafloor mapping, even in shallow regions keeps being elusive. Challenges to this effort include cloud cover, surface sun-glint, and water turbidity caused by sediment resuspension and primary productivity. Nevertheless, using high-quality satellite imagery (Landsat-8 OLI -30x30m/pixel- and GeoEye-1 -2x2m/pixel) and rigorous pre-processing (atmospheric correction, de-glinting and water-column light extinction compensation), resulting data contribute towards the advancement of seafloor mapping. The Yucatan Peninsula in México is a carbonate ramp devoid of significant orographic features and surface water bodies. Its submerged portion is the Campeche Bank, gently sloping towards the Gulf of Mexico. The bottom features several distinct blankets composed by medium-fine sediment (dominated by pelecypods, gastropods, foraminifera, lithoclasts, calcareous peloids and algal nodules, Halimeda plaques and coralline algae fragments), and a reef unit with several bank-type coral reefs. Outside the coral reefs, biotic cover down to 20 m deep is dominated by macroalgae (red, brown, green), coralline and filamentous algae with sharp seasonal changes in abundance, from almost nil during north-winds (Oct. - Jan.) to high during dry (Feb.- May) and rainy seasons (Jun. - Sept.), with changes of dominance by algae groups between dry and rainy seasons. This bloom is favored by increases in sunlight and nutrients carried by the Caribbean current upwelling washing the Campeche Bank. Beyond 20 m depth, sandy plains dominate the seascape. Corals, octocorals, sponges and tunicates are spatially restricted to bottoms with thin layers of

  11. Online 3D EPID-based dose verification: Proof of concept

    International Nuclear Information System (INIS)

    Spreeuw, Hanno; Rozendaal, Roel; Olaciregui-Ruiz, Igor; González, Patrick; Mans, Anton; Mijnheer, Ben; Herk, Marcel van

    2016-01-01

    , including dose verification, took 266 ± 11 ms on a dual octocore Intel Xeon E5-2630 CPU running at 2.40 GHz. The introduced delivery errors were detected after 5–10 s irradiation time. Conclusions: A prototype online 3D dose verification tool using portal imaging has been developed and successfully tested for two different kinds of gross delivery errors. Thus, online 3D dose verification has been technologically achieved.

  12. Online 3D EPID-based dose verification: Proof of concept.

    Science.gov (United States)

    Spreeuw, Hanno; Rozendaal, Roel; Olaciregui-Ruiz, Igor; González, Patrick; Mans, Anton; Mijnheer, Ben; van Herk, Marcel

    2016-07-01

    266 ± 11 ms on a dual octocore Intel Xeon E5-2630 CPU running at 2.40 GHz. The introduced delivery errors were detected after 5-10 s irradiation time. A prototype online 3D dose verification tool using portal imaging has been developed and successfully tested for two different kinds of gross delivery errors. Thus, online 3D dose verification has been technologically achieved.

  13. Quantifying bamboo coral growth rate nonlinearity with the radiocarbon bomb spike: A new model for paleoceanographic chronology development

    Science.gov (United States)

    Frenkel, M. M.; LaVigne, M.; Miller, H. R.; Hill, T. M.; McNichol, A.; Gaylord, M. Lardie

    2017-07-01

    Bamboo corals, long-lived cold water gorgonin octocorals, offer unique paleoceanographic archives of the intermediate ocean. These Isididae corals are characterized by alternating gorgonin nodes and high Mg-calcite internodes, which synchronously extend radially. Bamboo coral calcite internodes have been utilized to obtain geochemical proxy data, however, growth rate uncertainty has made it difficult to construct precise chronologies for these corals. Previous studies have relied upon a single tie point from records of the anthropogenic Δ14C bomb spike preserved in the gorgonin nodes of live-collected corals to calculate a mean radial extension rate for the outer 50 years of skeletal growth. Bamboo coral chronologies are typically constructed by applying this mean extension rate to the entire coral record, assuming constant radial extension with coral age. In this study, we aim to test this underlying assumption by analyzing the organic nodes of six California margin bamboo corals at high enough resolution (bomb spike, including two tie points at 1957 and 1970, plus the coral collection date (2007.5) for four samples. Radial extension rates between tie points ranged from 10 to 204 μm/year, with a decrease in growth rate evident between the 1957-1970 and 1970-2007.5 periods for all four corals. A negative correlation between growth rate and coral radius (r =-0.7; p=0.04) was determined for multiple bamboo coral taxa and individuals from the California margin, demonstrating a decline in radial extension rate with specimen age and size. To provide a mechanistic basis for these observations, a simple mathematical model was developed based on the assumption of a constant increase in circular cross sectional area with time to quantify this decline in radial extension rate with coral size between chronological tie points. Applying the area-based model to our Δ14C bomb spike time series from individual corals improves chronology accuracy for all live-collected corals

  14. Discoveries and Conservation Efforts of Extensive Deep-Sea Coral Habitat off the Southeastern U.S.

    Science.gov (United States)

    Reed, J. K.; Messing, C. G.; Walker, B. K.; Farrington, S.; Brooke, S.; Correa, T.; Brouwer, M.

    2012-12-01

    The deep-sea floor of the Western Atlantic off the southeastern U.S. supports a variety of deep-sea coral ecosystem (DSCE) habitats, including: coral mounds, rock terraces (Miami and Pourtalès Terraces), canyons (Agassiz and Tortugas Valleys), and island slopes (western Bahamas and northern Cuba). We used NOAA bathymetric contour maps and digital elevation models to identify and delineate the areal extent of potential DSCE habitat (50-1000 m) from northeastern Florida through the Straits of Florida. Recently, shipboard and AUV side-scan and multibeam sonar have further documented portions of the region. The resulting maps have been ground-truthed with over 250 submersible and remotely operated vehicle (ROV) dives, revealing that high-relief topographic features, including steep escarpments and rocky terraces, are good predictors of DSCE habitat in this region. The benthic biota is diverse but locally variable; for example, Lophelia and Enallopsammia stony corals dominate the deep-water mounds, whereas stylasterid corals dominate the rocky terraces where Lophelia is sporadic. Octocorals, black corals, and sponges are common at most sites but different species exhibit site-specific distributional variability. In 2011, the first of two NOAA-sponsored cruises using sonar mapping and an ROV discovered the southernmost Lophelia coral mound in the continental United States, south of the Florida Keys, offering the possibility that more Lophelia mounds may exist in this region where they were previously thought to be absent. The second cruise discovered that deep-water Oculina varicosa coral reefs extend over 70 nmi north of the current boundaries of the Oculina Habitat Area of Particular Concern (OHAPC), which was first designated as a marine protected area in 1984. These studies indicate that cold-water coral mounds are significantly more diverse and abundant in this region than previously thought. These research results were presented to NOAA and the South Atlantic

  15. Paleocommunity turnover in an Early Pliocene seamount from southeastern Spain

    Science.gov (United States)

    García-Ramos, Diego Antonio; Zuschin, Martin

    2017-04-01

    Seamounts are topographic elevations under the sea, regardless of their size and relief. They support rich living communities and are important biodiversity hotspots, but many of the fundamental ecological processes that maintain seamount communities remain poorly understood. In contrast to snapshot observations conducted on extant seamounts, fossil examples may provide the opportunity to assess how temporal changes in physico-chemical parameters relate to paleocommunity turnovers in these particular biotopes. Here we deal with an Early Pliocene (Zanclean) small seamount in southeastern Spain. This classic locality is extremely rich in fossil macroinvertebrates and was subject to studies of some taxonomic groups in the late seventies. However, the detailed stratigraphy is herein outlined for the first time. The overall feature is a shallowing upward succession about 35 m thick which onlaps a Miocene volcanic ridge. The occurrence of the planktonic foraminifera Globorotalia margaritae and G. puncticulata allow attribution to the MPl3 biozone of the Mediterranean Pliocene. We measured two sections that can be divided in a lower interval of fine-grained bryozoan-rich deposits and a upper interval of biocalcarenite increasingly rich in rhodoliths upsection. The whole series is bioturbated, with Thalassinoides traces being more common upsection. Biofabrics comprise mostly densely-packed suites of disarticulated and fragmented shells of calcitic fauna (large oysters are often bioeroded by clionid sponges), suggesting relatively low sedimentation rates and reworking by storms (e.g., channelized shell-beds, tubular tempestites). The prevailing taxonomic groups are cheilostome bryozoans, oysters, brachiopods, pectinids, echinoderms, cirripedes and corals. The lower interval contains octocoral internodes (Isididae) (only recorded at the base of the section). Scleratinians like Balanophyllia? decrease in abundance upsection. Bryozoans are extremely abundant and diverse, with

  16. Severity of the 1998 and 2005 bleaching events in Venezuela, southern Caribbean

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    Sebastián Rodríguez

    2010-10-01

    Full Text Available This study describes the severity of the 2005 bleaching event at 15 reef sites across Venezuela and compares the 1998 and 2005 bleaching events at one of them. During August and September 2005, bleached corals were first observed on oceanic reefs rather than coastal reefs, affecting 1 to 4% of coral colonies in the community (3 reef sites, n=736 colonies. At that time, however, no bleached corals were recorded along the eastern coast of Venezuela, an area of seasonal upwelling (3 reefs, n=181 colonies. On coastal reefs, bleaching started in October but highest levels were reached in November 2005 and January 2006, when 16% of corals were affected among a wide range of taxa (e.g. scleractinians, octocorals, Millepora and zoanthids. In the Acropora habitats of Los Roques (an oceanic reef, no bleached was recorded in 2005 (four sites, n=643 colonies. At Cayo Sombrero, a coastal reef site, bleaching was less severe in 1998 than in 2005 (9% of the coral colonies involving 2 species vs. 26% involving 23 species, respectively. Our results indicate that bleaching was more severe in 2005 than in 1998 on Venezuelan reefs; however, no mass mortality was observed in either of these two events. Rev. Biol. Trop. 58 (Suppl. 3: 189-196. Epub 2010 October 01.En este estudio se describe la severidad del evento de blanqueamiento del 2005 en 15 arrecifes coralinos de Venezuela, y se compara con el ocurrido en 1998 para uno de esos arrecifes. Los primeros corales blanqueados se observaron en agosto y septiembre 2005, en arrecifes oceánicos en lugar de costeros, afectando entre 1 y 4% de las colonias coralinas (3 arrecifes, n= 736 colonias. Para ese momento, tampoco se había detectado blanqueamiento en áreas oceánicas de la costa este de Venezuela (3 arrecifes, n= 181 colonias, donde ocurre una surgencia estacional. En arrecifes costeros, el blanqueamiento comenzó en octubre pero alcanzó su máximo entre noviembre 2005 y enero 2006, afectando hasta el 16% de

  17. Arrecifes coralinos de Bocas del Toro, Panamá: IV. Distribución, estructura y estado de conservación de los arrecifes continentales de Península Valiente

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    Héctor M. Guzmán

    2001-03-01

    lo que justifica, una vez más, la necesidad de modificar el área protegida actual de forma que se incorpore dentro de los planes de conservación este nuevo sector.This is the fourth and last contribution describing the individual structure, distribution and conservation status of coral reefs in the Province of Bocas del Toro. Here we describe 14 new reefs along 129 km of coast from Peninsula Valiente to Río Calovébora. Average live coral coverage for this region was 17.1% (" 3.6%, mainly in the western region of the peninsula (Bahia Bluefield and Ensenada Tobobe. Coral cover increases with depth ( 5 m for most species at several reefs and the corals Porites furcata and Acropora palmata dominated shallow waters. Acropora palmata was found abundant in 43% of the studied reefs and toward the regions of the Ensenada Tobobe and Punta Valiente. Coral recruitment rates were similar in distribution to those reefs with greater coral coverage, with average densities of 4 recruit/m² (maximum 9 recruits/m² and mainly Agaricia spp., Porites astreoides and Siderastrea siderea. The greater diversity of corals and sponges was recorded toward the western side of the peninsula, with a total of 55 coral species in the study area, including two new records for Bocas del Toro (59 species in total, Dichocoenia stellaris and Madracis luciphila and increasing the diversity of corals of Panama to 65 species. We found 24 species of octocorals and Gorgonia mariae, Muriceopsis sulphurea and Muricea laxaoosens, are informed for the first time to the area, increasing in 10% the diversity for Bocas del Toro (32 in total. We recorded 48 sponges, including five new species for the area and representing an increase of 9% in the total number (58. Large populations of Acropora palmata were found in the Ensenada Tobobe, what justifies once again the need for modifying the existing protected area, so that this new region is incorporated within the conservation plans.