Invasion and persistence of a selfish gene in the Cnidaria.

Science.gov (United States)

Goddard, Matthew R; Leigh, Jessica; Roger, Andrew J; Pemberton, Andrew J

2006-12-20

Homing endonuclease genes (HEGs) are superfluous, but are capable of invading populations that mix alleles by biasing their inheritance patterns through gene conversion. One model suggests that their long-term persistence is achieved through recurrent invasion. This circumvents evolutionary degeneration, but requires reasonable rates of transfer between species to maintain purifying selection. Although HEGs are found in a variety of microbes, we found the previous discovery of this type of selfish genetic element in the mitochondria of a sea anemone surprising. We surveyed 29 species of Cnidaria for the presence of the COXI HEG. Statistical analyses provided evidence for HEG invasion. We also found that 96 individuals of Metridium senile, from five different locations in the UK, had identical HEG sequences. This lack of sequence divergence illustrates the stable nature of Anthozoan mitochondria. Our data suggests this HEG conforms to the recurrent invasion model of evolution. Ordinarily such low rates of HEG transfer would likely be insufficient to enable major invasion. However, the slow rate of Anthozoan mitochondrial change lengthens greatly the time to HEG degeneration: this significantly extends the periodicity of the HEG life-cycle. We suggest that a combination of very low substitution rates and rare transfers facilitated metazoan HEG invasion.

Summer composition and distribution of the jellyfish (Cnidaria: Medusozoa in the shelf area off the central Mexican Pacific Composición y distribución de las medusas (Cnidaria: Medusozoa en la plataforma continental central del Pacifico mexicano

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Lourdes Segura-Puertas

2010-04-01

Full Text Available The composition, distribution, and abundance of the jellyfish community of a shelf area of the Mexican tropical Pacific were surveyed during August 1988. Zooplankton samples were collected along transects on the outer and inner sectors of the continental shelf to determine the structure of the jellyfish community and its variation in this area during the rainy season. A total of 23 species were recorded, with Aglaura hemistoma, Solmundella bitentaculata, Liriope tetraphylla, Pelagia noctiluca, and Rhopalonema velatum being the most abundant. The total abundance of medusae and of the most abundant species was statistically independent of depth and distance to the coast. Hence, the total jellyfish abundance of the most abundant species, and Shannon's Diversity index had a uniform distribution in both the inner and the outer shelf; furthermore, neritic-oceanic forms and oceanic species occurred indistinctly over the entire continental shelf. On the outer shelf A. hemistoma and S. bitentaculata were most abundant; the former species, together with L. tetraphylla, weakly characterized the inner shelf jellyfish community. The narrowness of the shelf, the wide distribution of the most abundant forms, and the possible effect of local advective processes from the oceanic zone masked a definite gradient across the shelf. Three species have not been recorded previously in the Mexican Pacific: Amphinema dinema (Péron and Lesueur, 1810, Sarsia coccometra Bigelow, 1909, and Clytia mccradyi (Brooks, 1888. The finding of A. dinema is the first in the Eastern Pacific.Se estudió la composición, distribución y abundancia de la comunidad de medusas de la plataforma continental en el Pacífico mexicano durante agosto 1988. Las muestras de zooplancton provienen de transectos en las zonas externa e interna de la plataforma para determinar la estructura de la comunidad de medusas y su variación durante la época de lluvias. Se identificaron 23 especies; las m

Specific inflammatory response of Anemonia sulcata (Cnidaria) after bacterial injection causes tissue reaction and enzymatic activity alteration.

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Trapani, M R; Parisi, M G; Parrinello, D; Sanfratello, M A; Benenati, G; Palla, F; Cammarata, M

2016-03-01

The evolution of multicellular organisms was marked by adaptations to protect against pathogens. The mechanisms for discriminating the ''self'' from ''non-self" have evolved into a long history of cellular and molecular strategies, from damage repair to the co-evolution of host-pathogen interactions. We investigated the inflammatory response in Anemonia sulcata (Cnidaria: Anthozoa) following injection of substances that varied in type and dimension, and observed clear, strong and specific reactions, especially after injection of Escherichia coli and Vibrio alginolyticus. Moreover, we analyzed enzymatic activity of protease, phosphatase and esterase, showing how the injection of different bacterial strains alters the expression of these enzymes and suggesting a correlation between the appearance of the inflammatory reaction and the modification of enzymatic activities. Our study shows for the first time, a specific reaction and enzymatic responses following injection of bacteria in a cnidarian. Copyright © 2016 Elsevier Inc. All rights reserved.

Overview of the genus Briareum (Cnidaria, Octocorallia, Briareidae) in the Indo-Pacific, with the description of a new species.

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Samimi-Namin, Kaveh; van Ofwegen, Leen P

2016-01-01

The status of Indo-Pacific Briareum species (Cnidaria, Octocorallia, Briareidae) is reviewed by presenting their sclerite features and habitus descriptions. Following the re-examination of type material, museum specimens and newly collected specimens, a species identification key is provided. The species distributions are discussed and updated distribution ranges are depicted. Moreover, a new taxon, Briareum cylindrum sp. n. is described and depicted, whereas Briareum excavatum (Nutting, 1911) is synonymised with Briareum stechei (Kükenthal, 1908). Briareum hamrum (Gohar, 1948) is recorded from the Persian Gulf and Oman Sea for the first time. Consequently, in total four Briareum species are recognized in the Indo-Pacific; Briareum hamrum from the western Indian Ocean, and Briareum cylindrum sp. n., Briareum stechei, and Briareum violaceum from the central and eastern Indo-Pacific region.

Development and population growth of Hydra viridissima Pallas, 1766 (Cnidaria, Hydrozoa in the laboratory

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FC. Massaro

Full Text Available Hydras, the most representative freshwater Cnidaria, are of common occurrence in bodies of water in every continent except Antarctica. This study was planned with the aim of maintaining a population of Hydra viridissima in laboratory culture to enable the determination of the individual and population growth-rates of this species, as well as its population doubling time and generation time, with a view to employing these common animals as test-organisms in ecotoxicological assays. The organisms were maintained in reconstituted water at 20 ± 2 °C, illuminated at 800 lux with a photoperiod of 12 hours light: 12 hours dark, and were fed on neonates of the cladoceran Ceriodaphnia silvestrii (3 or 4 neonates per hydra, 3 times a week. The individual growth-rate (k of the species was 0.43, the maximum length of the column 2.53 mm and the generation time 6.6 ± 1.5 days on average. The hydra population showed an intrinsic growth-rate (r of 0.0468, according to the fitted curve, and a doubling time of 14.8 ± 2.63 days. Hydra viridissima is easy to grow in the laboratory and performs well in the conditions used in this study. It is thus a promising candidate test-organism for ecotoxicological studies.

Hallazgo de Symplectoscyphus bathyalis Vervoort, 1972 (Cnidaria, Hydrozoa en el Cañón de La Gaviera (Golfo de Vizcaya, España, Atlántico nordeste

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ALTUNA, A.

2012-01-01

Full Text Available Durante una campaña de muestreo en el Cañón de La Gaviera (Golfo de Vizcaya, España, Atlántico nordeste, se ha obtenido el hidrozoo Symplectoscyphus bathyalis Vervoort, 1972 (Cnidaria, Hydrozoa en dos estaciones a 700 m y 790 m de profundidad. Las colonias tienen gonosoma y son polisifónicas. La especie se ilustra y describe, actualizándose su distribución geográfica y batimétrica. Es el hallazgo realizado a menor profundidad en aguas europeas. La especie es nueva para la Península Ibérica.

Reaction of the mussel Mytilus galloprovincialis (Bivalvia) to Eugymnanthea inquilina (Cnidaria) and Urastoma cyprinae (Turbellaria) concurrent infestation.

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Mladineo, Ivona; Petrić, Mirela; Hrabar, Jerko; Bočina, Ivana; Peharda, Melita

2012-05-01

In total 480 individuals of Mytilus galloprovincialis were sampled monthly from October 2009 to September 2010, at the shellfish farm in the Mali Ston Bay, south Adriatic Sea (Croatia) in order to assess the extent of pathology imposed by two parasites, Eugymnanthea inquilina (Cnidaria) and Urastoma cyprinae (Turbellaria). Although a deteriorating impact on host reproduction or condition index was lacking, we evidenced ultrastructural and functional alteration in host cells at the attachment site. Ultrastructural changes included hemocytic encapsulation of the turbellarian and cell desquamation in medusoid infestation. Caspase positive reaction inferred by immunohistochemistry (IHC) was triggered in cases of turbellarian infestation, in contrast with hydroids, suggesting that the former exhibits more complex host-parasite interaction, reflected in the persistent attempts of the parasite to survive bivalve reaction. We have evidenced that both organisms trigger specific host reaction that although not costly in terms of host reproductive cycle or growth, results in mild tissue destruction and hemocyte activation. A lower degree of tissue reaction was observed in cases of hydroid infestation, compared to turbellarian. Copyright © 2012 Elsevier Inc. All rights reserved.

Gross and microscopic morphology of lesions in Cnidaria from Palmyra Atoll, Central Pacific

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Williams, Gareth J.; Work, Thierry M.; Aeby, Greta S.; Knapp, Ingrid S.; Davy, Simon K.

2011-01-01

We conducted gross and microscopic characterizations of lesions in Cnidaria from Palmyra Atoll, Central Pacific. We found growth anomalies (GA) to be the most commonly encountered lesion. Cases of discoloration and tissue loss were rare. GAs had a focal or multi-focal distribution and were predominantly nodular, exophytic, and umbonate. In scleractinians, the majority of GAs manifested as hyperplasia of the basal body wall (52% of cases), with an associated absence or reduction of polyp structure (mesenteries and filaments, actinopharynx and tentacles), and depletion of zooxanthellae in the gastrodermis of the upper body wall. In the soft corals Sinularia sp. and Lobophytum sp., GAs exclusively manifested as prominent hyperplasia of the coenenchyme with an increased density of solenia. In contrast to scleractinians, soft coral GAs displayed an inflammatory and necrotizing component with marked edema of the mesoglea, accompanied by infiltrates of variably-sized granular amoebocytes. Fungi, algae, sponges, and Crustacea were present in some scleractinian GAs, but absent in soft coral GAs. Fragmentation of tissues was a common finding in Acropora acuminata and Montipora cf. dilatata colonies with tissue loss, although no obvious causative agents were seen. Discoloration in the zoanthid, Palythoa tuberculosa, was found to be the result of necrosis, while in Lobophytum sp. discoloration was the result of zooxanthellar depletion (bleaching). Soft corals with discoloration or tissue loss showed a marked inflammatory response, however no obvious causative organisms were seen. Lesions that appeared similar at the gross level were revealed to be distinct by microscopy, emphasizing the importance of histopathology.

Notes on some sertulariid hydroids (Cnidaria: Hydrozoa from the tropical western Pacific, with descriptions of nine new species

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Horia R. Galea

2016-08-01

Full Text Available Forty-three species of sertulariid hydroids (Cnidaria: Hydrozoa: Sertulariidae, collected from the tropical western Pacific (Taiwan, Philippines, New Caledonia, French Polynesia, Vanuatu, Fiji, Tonga, Solomon Islands during various expeditions of the French Tropical Deep-Sea Benthos program, are discussed. Of these, nine are new to science: Gonaxia nova sp. nov., G. plumularioides sp. nov., Sertularella folliformis sp. nov., Se. plicata sp. nov., Se. pseudocatena sp. nov., Se. splendida sp. nov., Se. tronconica sp. nov., Se. tubulosa sp. nov., and Symplectoscyphus paucicatillus sp. nov. The subspecies Symplectoscyphus johnstoni (Gray, 1843 tropicus Vervoort, 1993 is raised to species but, in order to avoid the secondary homonymy with Sy. tropicus (Hartlaub, 1901, the replacement name, Sy. fasciculatus nom. nov., is introduced. The male and female gonothecae of Diphasia cristata Billard, 1920, the male gonothecae of Gonaxia elegans Vervoort, 1993, as well as the female gonothecae of Salacia macer Vervoort & Watson, 2003, are described for the first time. Additional notes on the morphology of several other species are provided. All taxa are illustrated, in most cases using figures drawn at the same scale, so as to highlight the differences between related species.

Genetic diversity and genetic similarities between Iranian rose species

NARCIS (Netherlands)

Samiei, L.; Naderi, R.; Khalighi, A.; Shahnejat-Bushehri, A.A.; Mozaffarian, V.; Esselink, G.D.; Kazempour Osaloo, S.; Smulders, M.J.M.

2010-01-01

Wild rose species were collected from different regions of Iran for a rose breeding programme. They included accessions from Rosa persica, R. foetida, R. pimpinellifolia, R. hemisphaerica, R. canina, R. iberica, R. damascena, R. beggeriana, and R. orientalis. Ten microsatellite (simple sequence

Four new species and one new genus of zoanthids (Cnidaria, Hexacorallia from the Galapagos Islands

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James Reimer

2010-04-01

Full Text Available Recent research has confirmed the presence of several species of undescribed macrocnemic zoanthids (Cnidaria: Hexacorallia: Zoantharia: Macrocnemina in the Galapagos. In this study four new species, including two belonging to a new genus, are described. Two species, Terrazoanthus onoi sp. n. and Terrazoanthus sinnigeri sp. n., both belong within the recently erected family Hydrozoanthidae to the new genus Terrazoanthus, which can be distinguished from the type genus Hydrozoanthus by being attached to abiotic substrate as opposed to hydrozoans for Hydrozoanthus. Each new species of zoanthid can be clearly distinguished by a number of characters. Antipathozoanthus hickmani sp. n. is distinguished by its exclusive association with the antipatharian Antipathes galapagensis, and has approximately 40 tentacles. Parazoanthus darwini sp. n. is distinguished by its frequent association with sponges, with approximately 24–30 tentacles and polyps embedded in a well-developed coenenchyme. T. onoi sp. n. is distinguished by its bright red oral disk color, 32–40 tentacles, and has only basitrichs and mastigophores present in the pharynx. T. sinnigeri sp. n. is distinguished by usually occurring on the underside of rubble and rocks on sandy bottoms, showing 30–36 tentacles, and numerous nematocyst types in the pharynx. The two Terrazoanthus species, although divergent in both morphology and ecology, are apparently very closely related, with identical mitochondrial 16S ribosomal DNA and cytochrome oxidase subunit I sequences. These two species can be molecularly distinguished by their subtly different yet distinct sequences of internal transcribed spacer of ribosomal DNA (ITS-rDNA.

Type material of Acanthocephala, Nematoda and other non-helminths phyla (Cnidaria, Annelida, and Arthropoda housed in the Helminthological Collection of the Oswaldo Cruz Institute/ FIOCRUZ (CHIOC, Rio de Janeiro, Brazil, from 1979 to 2016

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Daniela A. Lopes

2017-10-01

Full Text Available The third part of the catalogue of type material in the Helminthological Collection of the Oswaldo Cruz Institute/FIOCRUZ (CHIOC, comprising types deposited between 1979 and 2016, is presented to complement the first list of all types that was published in 1979. This part encompasses Acanthocephala, Nematoda and the other non-helminth phyla Cnidaria, Annelida, and Arthropoda. Platyhelminthes was covered in the first (Monogenoidea and second (Rhabditophora Trematoda and Cestoda parts of the catalogue published in September 2016 and March 2017, respectively. The present catalogue comprises type material for 116 species distributed across five phyla, nine classes, 50 families, and 80 genera. Specific names are listed systematically, followed by type host, infection site, type locality, and specimens with their collection numbers and references. Species classification and nomenclature are updated.

The Holo-Transcriptome of the Zoantharian Protopalythoa variabilis (Cnidaria: Anthozoa: A Plentiful Source of Enzymes for Potential Application in Green Chemistry, Industrial and Pharmaceutical Biotechnology

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Jean-Étienne R. L. Morlighem

2018-06-01

Full Text Available Marine invertebrates, such as sponges, tunicates and cnidarians (zoantharians and scleractinian corals, form functional assemblages, known as holobionts, with numerous microbes. This type of species-specific symbiotic association can be a repository of myriad valuable low molecular weight organic compounds, bioactive peptides and enzymes. The zoantharian Protopalythoa variabilis (Cnidaria: Anthozoa is one such example of a marine holobiont that inhabits the coastal reefs of the tropical Atlantic coast and is an interesting source of secondary metabolites and biologically active polypeptides. In the present study, we analyzed the entire holo-transcriptome of P. variabilis, looking for enzyme precursors expressed in the zoantharian-microbiota assemblage that are potentially useful as industrial biocatalysts and biopharmaceuticals. In addition to hundreds of predicted enzymes that fit into the classes of hydrolases, oxidoreductases and transferases that were found, novel enzyme precursors with multiple activities in single structures and enzymes with incomplete Enzyme Commission numbers were revealed. Our results indicated the predictive expression of thirteen multifunctional enzymes and 694 enzyme sequences with partially characterized activities, distributed in 23 sub-subclasses. These predicted enzyme structures and activities can prospectively be harnessed for applications in diverse areas of industrial and pharmaceutical biotechnology.

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

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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.

Transition elements in tabulate coral skeletons: seawater vs. sediment

Czech Academy of Sciences Publication Activity Database

Hladil, Jindřich; Voltr, J.

2003-01-01

Roč. 7, 9th International Symposium on Fossil Cnidaria and Porifera Abstracts. (2003), s. 36 ISSN 1608-8166. [International Symposium on Fossil Cnidaria and Porifera /9./. 03.08.2003-07.08.2003, Graz] R&D Projects: GA AV ČR IAA3013209 Institutional research plan: CEZ:AV0Z3013912 Keywords : transition elements * coral increments * Devonian Subject RIV: DB - Geology ; Mineralogy

Rapid divergence of histones in Hydrozoa (Cnidaria) and evolution of a novel histone involved in DNA damage response in hydra.

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Reddy, Puli Chandramouli; Ubhe, Suyog; Sirwani, Neha; Lohokare, Rasika; Galande, Sanjeev

2017-08-01

Histones are fundamental components of chromatin in all eukaryotes. Hydra, an emerging model system belonging to the basal metazoan phylum Cnidaria, provides an ideal platform to understand the evolution of core histone components at the base of eumetazoan phyla. Hydra exhibits peculiar properties such as tremendous regenerative capacity, lack of organismal senescence and rarity of malignancy. In light of the role of histone modifications and histone variants in these processes it is important to understand the nature of histones themselves and their variants in hydra. Here, we report identification of the complete repertoire of histone-coding genes in the Hydra magnipapillata genome. Hydra histones were classified based on their copy numbers, gene structure and other characteristic features. Genomic organization of canonical histone genes revealed the presence of H2A-H2B and H3-H4 paired clusters in high frequency and also a cluster with all core histones along with H1. Phylogenetic analysis of identified members of H2A and H2B histones suggested rapid expansion of these groups in Hydrozoa resulting in the appearance of unique subtypes. Amino acid sequence level comparisons of H2A and H2B forms with bilaterian counterparts suggest the possibility of a highly mobile nature of nucleosomes in hydra. Absolute quantitation of transcripts confirmed the high copy number of histones and supported the canonical nature of H2A. Furthermore, functional characterization of H2A.X.1 and a unique variant H2A.X.2 in the gastric region suggest their role in the maintenance of genome integrity and differentiation processes. These findings provide insights into the evolution of histones and their variants in hydra. Copyright © 2017 Elsevier GmbH. All rights reserved.

Specific Vicariance of Two Primeval Lowland Forest Lichen Indicators

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Kubiak, Dariusz; Osyczka, Piotr

2017-06-01

To date, the lichens Chrysothrix candelaris and Varicellaria hemisphaerica have been classified as accurate primeval lowland forest indicators. Both inhabit particularly valuable remnants of oak-hornbeam forests in Europe, but tend toward a specific kind of vicariance on a local scale. The present study was undertaken to determine habitat factors responsible for this phenomenon and verify the indicative and conservation value of these lichens. The main spatial and climatic parameters that, along with forest structure, potentially affect their distribution patterns and abundance were analysed in four complexes with typical oak-hornbeam stands in NE Poland. Fifty plots of 400 m2 each were chosen for detailed examination of stand structure and epiphytic lichens directly associated with the indicators. The study showed that the localities of the two species barely overlap within the same forest community in a relatively small geographical area. The occurrence of Chrysothrix candelaris depends basically only on microhabitat space provided by old oaks and its role as an indicator of the ecological continuity of habitat is limited. Varicellaria hemisphaerica is not tree specific but a sufficiently high moisture of habitat is essential for the species and it requires forests with high proportion of deciduous trees in a wide landscape scale. Local landscape-level habitat continuity is more important for this species than the current age of forest stand. Regardless of the indicative value, localities of both lichens within oak-hornbeam forests deserve the special protection status since they form unique assemblages of exclusive epiphytes, including those with high conservation value.

Hidden among Sea Anemones: The First Comprehensive Phylogenetic Reconstruction of the Order Actiniaria (Cnidaria, Anthozoa, Hexacorallia) Reveals a Novel Group of Hexacorals

Science.gov (United States)

Rodríguez, Estefanía; Barbeitos, Marcos S.; Brugler, Mercer R.; Crowley, Louise M.; Grajales, Alejandro; Gusmão, Luciana; Häussermann, Verena; Reft, Abigail; Daly, Marymegan

2014-01-01

Sea anemones (order Actiniaria) are among the most diverse and successful members of the anthozoan subclass Hexacorallia, occupying benthic marine habitats across all depths and latitudes. Actiniaria comprises approximately 1,200 species of solitary and skeleton-less polyps and lacks any anatomical synapomorphy. Although monophyly is anticipated based on higher-level molecular phylogenies of Cnidaria, to date, monophyly has not been explicitly tested and at least some hypotheses on the diversification of Hexacorallia have suggested that actiniarians are para- or poly-phyletic. Published phylogenies have demonstrated the inadequacy of existing morphological-based classifications within Actiniaria. Superfamilial groups and most families and genera that have been rigorously studied are not monophyletic, indicating conflict with the current hierarchical classification. We test the monophyly of Actiniaria using two nuclear and three mitochondrial genes with multiple analytical methods. These analyses are the first to include representatives of all three currently-recognized suborders within Actiniaria. We do not recover Actiniaria as a monophyletic clade: the deep-sea anemone Boloceroides daphneae, previously included within the infraorder Boloceroidaria, is resolved outside of Actiniaria in several of the analyses. We erect a new genus and family for B. daphneae, and rank this taxon incerti ordinis. Based on our comprehensive phylogeny, we propose a new formal higher-level classification for Actiniaria composed of only two suborders, Anenthemonae and Enthemonae. Suborder Anenthemonae includes actiniarians with a unique arrangement of mesenteries (members of Edwardsiidae and former suborder Endocoelantheae). Suborder Enthemonae includes actiniarians with the typical arrangement of mesenteries for actiniarians (members of former suborders Protantheae, Ptychodacteae, and Nynantheae and subgroups therein). We also erect subgroups within these two newly-erected suborders

Hidden among sea anemones: the first comprehensive phylogenetic reconstruction of the order Actiniaria (Cnidaria, Anthozoa, Hexacorallia reveals a novel group of hexacorals.

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Estefanía Rodríguez

Full Text Available Sea anemones (order Actiniaria are among the most diverse and successful members of the anthozoan subclass Hexacorallia, occupying benthic marine habitats across all depths and latitudes. Actiniaria comprises approximately 1,200 species of solitary and skeleton-less polyps and lacks any anatomical synapomorphy. Although monophyly is anticipated based on higher-level molecular phylogenies of Cnidaria, to date, monophyly has not been explicitly tested and at least some hypotheses on the diversification of Hexacorallia have suggested that actiniarians are para- or poly-phyletic. Published phylogenies have demonstrated the inadequacy of existing morphological-based classifications within Actiniaria. Superfamilial groups and most families and genera that have been rigorously studied are not monophyletic, indicating conflict with the current hierarchical classification. We test the monophyly of Actiniaria using two nuclear and three mitochondrial genes with multiple analytical methods. These analyses are the first to include representatives of all three currently-recognized suborders within Actiniaria. We do not recover Actiniaria as a monophyletic clade: the deep-sea anemone Boloceroides daphneae, previously included within the infraorder Boloceroidaria, is resolved outside of Actiniaria in several of the analyses. We erect a new genus and family for B. daphneae, and rank this taxon incerti ordinis. Based on our comprehensive phylogeny, we propose a new formal higher-level classification for Actiniaria composed of only two suborders, Anenthemonae and Enthemonae. Suborder Anenthemonae includes actiniarians with a unique arrangement of mesenteries (members of Edwardsiidae and former suborder Endocoelantheae. Suborder Enthemonae includes actiniarians with the typical arrangement of mesenteries for actiniarians (members of former suborders Protantheae, Ptychodacteae, and Nynantheae and subgroups therein. We also erect subgroups within these two newly

Dendrogramma, new genus, with two new non-bilaterian species from the marine bathyal of southeastern Australia (Animalia, Metazoa incertae sedis--with similarities to some medusoids from the Precambrian Ediacara.

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Jean Just

Full Text Available A new genus, Dendrogramma, with two new species of multicellular, non-bilaterian, mesogleal animals with some bilateral aspects, D. enigmatica and D. discoides, are described from the south-east Australian bathyal (400 and 1000 metres depth. A new family, Dendrogrammatidae, is established for Dendrogramma. These mushroom-shaped organisms cannot be referred to either of the two phyla Ctenophora or Cnidaria at present, because they lack any specialised characters of these taxa. Resolving the phylogenetic position of Dendrogramma depends much on how the basal metazoan lineages (Ctenophora, Porifera, Placozoa, Cnidaria, and Bilateria are related to each other, a question still under debate. At least Dendrogramma must have branched off before Bilateria and is possibly related to Ctenophora and/or Cnidaria. Dendrogramma, therefore, is referred to Metazoa incertae sedis. The specimens were fixed in neutral formaldehyde and stored in 80% ethanol and are not suitable for molecular analysis. We recommend, therefore, that attempts be made to secure new material for further study. Finally similarities between Dendrogramma and a group of Ediacaran (Vendian medusoids are discussed.

African Zoology - Vol 27, No 3 (1992)

African Journals Online (AJOL)

A new record of Craspedacusta sowerbii (Cnidaria: Limnomedusae) from southern Africa · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. Nancy A. Rayner, C.C. Appleton, 143-145 ...

A checklist of butterflies of Dakshina Kannada District, Karnataka, India

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Deepak Naik

2016-10-01

Full Text Available In a preliminary study on the butterflies of Dakshina Kannada District, located in the southwestern part of the Karnataka along the Western Ghats in Karnataka State in India, a total of 172 species of butterflies belonging to 117 genera, from six families was prepared by visiting various landscapes during the period September 2012 to December 2015.  Of the various species recorded, Papilio clytia (Linnaeus, Papilio lio medon (Moore, Pachlio ptahector (Linnaeus, Castalius rosimon (Fabricius, Acytolepis puspa (Horsefield, Lethe europa (Fabricius, Neptis jumbah (Moore, Dophlae velina (Stoll, Hypolimnas misippus (Linnaeus and Doleschallia bisaltide (Cramer comes under the Schedule I of the Indian Wildlife Protection Act 1972.  The present study provides the baseline data of butterfly species of Dakshina Kannada. 

Nejstarší doklad existence svalové tkáně? Nové zkameněliny z konce starohor

Czech Academy of Sciences Publication Activity Database

Mikuláš, Radek

2015-01-01

Roč. 94, č. 1 (2015), s. 31-34 ISSN 0042-4544 Institutional support: RVO:67985831 Keywords : paleontology * fossil s * Eumetazoa * Cnidaria * Bilateralia * Ediacaran fauna * Proterozoic * muscle tissue * fossil footprints * movement of animals Subject RIV: DB - Geology ; Mineralogy

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 ...

Chemical and biological characterization of a crude venom extract ...

African Journals Online (AJOL)

Background: Sea-anemones, in common with other members of the phylum cnidaria (coelenterate) possess numerous tentacles containing specialized stinging cells of cnidocysts. Our main objective is to elucidate the chemical character and biological properties of this Nigerian species of sea anemone Bunodosoma ...

The Occurrence of Type S1A Serine Proteases in Sponge and Jellyfish

Science.gov (United States)

Rojas, Ana; Doolittle, Russell F.

2003-01-01

Although serine proteases are found in all kinds of cellular organisms and many viruses, the classic "chymotrypsin family" (Group S1A by th e 1998 Barrett nomenclature) has an unusual phylogenetic distribution , being especially common in animals, entirely absent from plants and protists, and rare among fungi. The distribution in Bacteria is larg ely restricted to the genus Streptomyces, although a few isolated occ urrences in other bacteria have been reported. The family may be enti rely absent from Archaea. Although more than a thousand sequences have been reported for enzymes of this type from animals, none of them ha ve been from early diverging phyla like Porifera or Cnidaria, We now report the existence of Group SlA serine proteases in a sponge (phylu m Porifera) and a jellyfish (phylum Cnidaria), making it safe to conc lude that all animal groups possess these enzymes.

Field Note

African Journals Online (AJOL)

the broadcast spawning coral Acropora millepora. Marine Ecology Progress Series 362: 129-137. Benzoni F, Basso D, Caragnano A, Rodondi G (2011) Hydrolithon spp. (Rhodophyta, Corallinales) overgrow live corals (Cnidaria, Scleractinia) in Yemen. Marine Biology 158: 2419-2428. Figure 1. Hydrolithon sp. overgrowing ...

Zooplankton diversity across three Red Sea reefs using pyrosequencing

KAUST Repository

Pearman, John K.; El-Sherbiny, Mohsen M.; Lanzé n, Anders; Al-Aidaroos, Ali M.; Irigoien, Xabier

2014-01-01

% sequence similarity. A total of 754 and 854 metazoan OTUs were observed in the data set for the 1380F and 1389F primer sets respectively. The phylum Arthropoda dominated both primer sets accounting for ~60% of reads followed by Cnidaria (~20%). Only about

The telomere repeat motif of basal Metazoa

Czech Academy of Sciences Publication Activity Database

Traut, W.; Szczepanowski, M.; Vítková, Magda; Opitz, Ch.; Marec, František; Zrzavý, Jan

2007-01-01

Roč. 15, č. 3, (2007), s. 371-382 ISSN 0967-3849 R&D Projects: GA ČR GA206/06/1860 Institutional research plan: CEZ:AV0Z50070508 Keywords : ancestral telomere * Choanozoa * Cnidaria Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.469, year: 2007

Structural Molecular Components of Septate Junctions in Cnidarians Point to the Origin of Epithelial Junctions in Eukaryotes

KAUST Repository

Ganot, P.

2014-09-21

Septate junctions (SJs) insure barrier properties and control paracellular diffusion of solutes across epithelia in invertebrates. However, the origin and evolution of their molecular constituents in Metazoa have not been firmly established. Here, we investigated the genomes of early branching metazoan representatives to reconstruct the phylogeny of the molecular components of SJs. Although Claudins and SJ cytoplasmic adaptor components appeared successively throughout metazoan evolution, the structural components of SJs arose at the time of Placozoa/Cnidaria/Bilateria radiation. We also show that in the scleractinian coral Stylophora pistillata, the structural SJ component Neurexin IV colocalizes with the cortical actin network at the apical border of the cells, at the place of SJs. We propose a model for SJ components in Cnidaria. Moreover, our study reveals an unanticipated diversity of SJ structural component variants in cnidarians. This diversity correlates with gene-specific expression in calcifying and noncalcifying tissues, suggesting specific paracellular pathways across the cell layers of these diploblastic animals.

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), ...

Sciences's Super Star

Science.gov (United States)

Magie, Craig; Bossert, Patricia; Aramli, Lili; Thomsen, Gerald

2016-01-01

Animal biology is fascinating for its incredible diversity in life strategies. These strategies amaze scientists and can also fire the enthusiasm of science students. One group of animals impressive in this way is the phylum "Cnidaria," containing some 10,000 invertebrate species that include jellyfish, corals, sea anemones, hydroids,…

First records of illegal harvesting and trading of black corals ...

African Journals Online (AJOL)

Black corals (Cnidaria: Antipatharia) have been used all around the world for a long time, whether as money or for medicinal purposes and jewellery manufacturing. Except in Hawaii where these fisheries are well known, black coral harvests are usually made without any control or any management. This is the case in many ...

The spectral sensitivity of the lens eyes of a box jellyfish, Tripedalia cystophora (Conant)

DEFF Research Database (Denmark)

Coates, Melissa M; Garm, Anders; Theobald, Jamie C

2006-01-01

Box jellyfish, or cubomedusae (class Cubozoa), are unique among the Cnidaria in possessing lens eyes similar in morphology to those of vertebrates and cephalopods. Although these eyes were described over 100 years ago, there has been no work done on their electrophysiological responses to light. ...... result from the presence of a single receptor type containing a single opsin. The peak sensitivity is to blue-green light. Visual pigment template fits indicate a vitamin A-1 based opsin with peak sensitivity near 500 nm for both eye types.......Box jellyfish, or cubomedusae (class Cubozoa), are unique among the Cnidaria in possessing lens eyes similar in morphology to those of vertebrates and cephalopods. Although these eyes were described over 100 years ago, there has been no work done on their electrophysiological responses to light. We...... used an electroretinogram (ERG) technique to measure spectral sensitivity of the lens eyes of the Caribbean species Tripedalia cystophora. The cubomedusae have two kinds of lens eyes, the lower and upper lens eyes. We found that both lens eye types have similar spectral sensitivities, which likely...

(Cnidaria: Limnomedusae) from southern Africa

African Journals Online (AJOL)

1992-01-27

Jan 27, 1992 ... the 1940s, when a number of exotic species were introduced, associated with man's ... its distribution from Europe, North America and China. 143. (Dejdar 1934 ... inter-basin transfers. The appearance of freshwater medusae.

Photosynthetic planulae and planktonic hydroids: contrasting strategies of propagule survival

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Patrizia Pagliara

2000-12-01

Full Text Available Settlement delays can be important to prevent propagule waste when proper settling substrates are not immediately available. Under laboratory conditions, the planulae of Clytia viridicans underwent two alternative developmental patterns. Some settled on the bottom, forming a hydranth-gonotheca complex that produced up to four medusae and later either degenerated or gave rise to a hydroid colony. Other planulae settled right below the air-water interface, forming floating colonies that eventually fell to the bottom and settled. Halecium nanum released planulae with a rich population of symbiotic zooxanthellae that survived into a rearing jar for three months. After a long period of apparent quiescence (possibly fuelled by photosynthetic activities of zooxanthellae the planulae produced new colonies. Both photosynthetic planulae and settlement at the interface air-water allow a delay in the passage from a planktonic to a fully functional benthic life.

Browse Title Index

African Journals Online (AJOL)

Items 76 - 100 of 1853 ... Vol 27, No 3 (1992), A new record of Craspedacusta sowerbii (Cnidaria: Limnomedusae) from southern Africa, Abstract PDF. Nancy A. Rayner, C.C. Appleton. Vol 5, No 2 (1970), A new record of a moerisiid hydroid from South Africa, Abstract PDF. NAH Millard. Vol 27, No 4 (1992), A new sandperch, ...

Zooplankton diversity across three Red Sea reefs using pyrosequencing

KAUST Repository

Pearman, John K.

2014-07-30

Coral reefs are considered among the most diverse ecosystems on Earth, yet little is known about the diversity of plankton in the surrounding water column. Moreover, few studies have utilized genomic methods to investigate zooplankton diversity in any habitat. This study investigated the diversity of taxa by sampling 45 stations around three reef systems in the central/southern Red Sea. The diversity of metazoan plankton was investigated by targeting the 18S rRNA gene and clustering OTUs at 97% sequence similarity. A total of 754 and 854 metazoan OTUs were observed in the data set for the 1380F and 1389F primer sets respectively. The phylum Arthropoda dominated both primer sets accounting for ~60% of reads followed by Cnidaria (~20%). Only about 20% of OTUs were shared between all three reef systems and the relation between geographic distance and Jaccard Similarity measures was not significant. Cluster analysis showed that there was no distinct split between reefs and stations from different reefs clustered together both for metazoans as a whole and for the phyla Arthropoda, Cnidaria and Chordata separately. This suggests that distance may not be a determining factor in the taxonomic composition of stations.

GFP-like proteins as ubiquitous metazoan superfamily: evolution of functional features and structural complexity.

Science.gov (United States)

Shagin, Dmitry A; Barsova, Ekaterina V; Yanushevich, Yurii G; Fradkov, Arkady F; Lukyanov, Konstantin A; Labas, Yulii A; Semenova, Tatiana N; Ugalde, Juan A; Meyers, Ann; Nunez, Jose M; Widder, Edith A; Lukyanov, Sergey A; Matz, Mikhail V

2004-05-01

Homologs of the green fluorescent protein (GFP), including the recently described GFP-like domains of certain extracellular matrix proteins in Bilaterian organisms, are remarkably similar at the protein structure level, yet they often perform totally unrelated functions, thereby warranting recognition as a superfamily. Here we describe diverse GFP-like proteins from previously undersampled and completely new sources, including hydromedusae and planktonic Copepoda. In hydromedusae, yellow and nonfluorescent purple proteins were found in addition to greens. Notably, the new yellow protein seems to follow exactly the same structural solution to achieving the yellow color of fluorescence as YFP, an engineered yellow-emitting mutant variant of GFP. The addition of these new sequences made it possible to resolve deep-level phylogenetic relationships within the superfamily. Fluorescence (most likely green) must have already existed in the common ancestor of Cnidaria and Bilateria, and therefore GFP-like proteins may be responsible for fluorescence and/or coloration in virtually any animal. At least 15 color diversification events can be inferred following the maximum parsimony principle in Cnidaria. Origination of red fluorescence and nonfluorescent purple-blue colors on several independent occasions provides a remarkable example of convergent evolution of complex features at the molecular level.

The Mauve Stinger Pelagia noctiluca (Forsskål, 1775. Distribution, Ecology, Toxicity and Epidemiology of Stings.

Directory of Open Access Journals (Sweden)

Luigi Pane

2008-09-01

Full Text Available The toxicity of Cnidaria is a subject of concern due to its influence on humans. In particular, jellyfish blooms can highly affect human economical activities, such as bathing, fishery, tourism, etc., as well as the public health. Stinging structures of Cnidaria (nematocysts produce remarkable effects on human skin, such as erythema, swelling, burning and vesicles, and at times further severe dermonecrotic, cardio- and neurotoxic effects, which are particularly dangerous in sensitive subjects. In several zones the toxicity of jellyfish is a very important health problem, thus it has stimulated the research on these organisms; to date toxicological research on Cnidarian venoms in the Mediterranean region is not well developed due to the weak poisonousness of venoms of jellyfish and anemones living in this area. In spite of this, during last decades several problems were also caused in the Mediterranean by stinging consequent to Cnidarian blooms mainly caused by Pelagia noctiluca (Forsskål, 1775 which is known to be the most venomous Mediterranean jellyfish. This paper reviews the knowledge on this jellyfish species, particularly considering its occurrence and toxicity.

Macroepizoísmo em Libinia ferreirae (Crustacea, Brachyura, Majidae Macroepizoites on Libinia ferreirae (Crustacea, Brachyura, Majidae

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Vanessa C. Winter

2006-06-01

Full Text Available Um estudo de distribuição dos macroepizóicos foi realizado numa população do caranguejo-aranha Libinia ferreirae Brito Capello, 1871 proveniente do litoral dos estados do Paraná e de Santa Catarina. O material biológico foi obtido junto aos pescadores, e faz parte do rejeito de pesca. Os caranguejos foram mensurados e os macroepizóicos identificados e contados. Os seguintes macroepizóicos sésseis foram registrados: Calliactis tricolor (Lesueur, 1817 (Cnidaria; Actiniaria (Cnidaria; Arca sp. (Mollusca; Ostreidae (Mollusca; Acanthodesia tenuis (Desor, 1848 (Bryozoa; Cirripedia e duas espécies tubícolas de Gammaridea (Crustacea. Além destes organismos ocorreram dois tubos desabitados e quatro animais vágeis. A anêmona C. tricolor foi a espécie mais abundante e freqüente, sendo, provavelmente, utilizada como mecanismo de camuflagem pelo caranguejo. O macroepizoísmo em L. ferreirae está relacionado com a idade ou tamanho do caranguejo, tendo maior incidência naqueles mais velhos ou de maior porte. Entretanto, a densidade dos macroepizóicos por caranguejo se mantém em torno de três. Não há relação entre o macroepizoísmo e o sexo do hospedeiro; somente fêmeas ovígeras utilizam desse recurso mais freqüentemente do que as não-ovígeras. Devido à maior área de fixação, os macroepizóicos colonizam principalmente a carapaça do caranguejo, enquanto nos pereiópodos há predominância de Bryozoa.A study of the distribution of the macroepizoites was carried out on a population of the spider crab Libinia ferreirae Brito Capello, 1871 from the Southern Brazilian coast. Crabs were obtained from shrimps and fishes by-catch. They were measured, and their macroepizoites were identified and counted. The following sessile macroepizoites were registered: Calliactis tricolor (Lesueur, 1817 (Cnidaria; Actiniaria (Cnidaria; Arca sp. (Mollusca; Ostreidae (Mollusca; Acanthodesia tenuis (Desor, 1848 (Bryozoa; Cirripedia and two species

Systematics of stalked jellyfishes (Cnidaria: Staurozoa

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Lucília S. Miranda

2016-05-01

Full Text Available Staurozoan classification is highly subjective, based on phylogeny-free inferences, and suborders, families, and genera are commonly defined by homoplasies. Additionally, many characters used in the taxonomy of the group have ontogenetic and intraspecific variation, and demand new and consistent assessments to establish their correct homologies. Consequently, Staurozoa is in need of a thorough systematic revision. The aim of this study is to propose a comprehensive phylogenetic hypothesis for Staurozoa, providing the first phylogenetic classification for the group. According to our working hypothesis based on a combined set of molecular data (mitochondrial markers COI and 16S, and nuclear markers ITS, 18S, and 28S, the traditional suborders Cleistocarpida (animals with claustrum and Eleutherocarpida (animals without claustrum are not monophyletic. Instead, our results show that staurozoans are divided into two groups, herein named Amyostaurida and Myostaurida, which can be distinguished by the absence/presence of interradial longitudinal muscles in the peduncle, respectively. We propose a taxonomic revision at the family and genus levels that preserves the monophyly of taxa. We provide a key for staurozoan genera and discuss the evolution of the main characters used in staurozoan taxonomy.

Influences of temperature and salinity on asexual reproduction and development of scyphozoan jellyfish from the British Isles

OpenAIRE

Widmer, Chad L.

2015-01-01

Jellyfish (Phylum Cnidaria, Class Scyphozoa) play important roles in pelagic ecosystems as predators and prey. Seasonally they form blooms facilitating reproductive success, but that are at times problematic for human enterprise. Medusa abundance has been correlated with environmental variables in several instances. However, the direct mechanisms for changes in medusa abundance are unclear. As global sea surface temperatures continue to change there is increasing concern that warming may enha...

Biological activities of secondary metabolites of the order Zoanthids

OpenAIRE

Zahra Aminikhoei; Zeinab Janahmadi; Iraj Nabipour

2015-01-01

The phylum Cnidaria is a large, diverse and ecologically important group of marine invertebrates, which produce powerful toxins and venoms. The number of marine natural product from cnidarians isolated from class Anthozoa. Among the Anthozoa, the order of zoanthids are sessile, clonal and mostly brightly colored invertebrate which produce high biodiversity of cytolitic, neurotoxic and cardiotoxic compounds. Zoanthids containing palytoxins are reportedly among the most toxic marine organisms k...

Pyrosequencing reveals diverse microbial community associated with the zoanthid Palythoa australiae from the South China Sea.

Science.gov (United States)

Sun, Wei; Zhang, Fengli; He, Liming; Li, Zhiyong

2014-05-01

Diverse sessile organisms inhabit the coral reef ecosystems, including corals, sponges, and sea anemones. In the past decades, scleractinian corals (Cnidaria, Anthozoa, Scleractinia) and their associated microorganisms have attracted much attention. Zoanthids (Cnidaria, Anthozoa, Zoanthidea) are commonly found in coral reefs. However, little is known about the community structure of zoanthid-associated microbiota. In this study, the microbial community associated with the zoanthid Palythoa australiae in the South China Sea was investigated by 454 pyrosequencing. As a result, 2,353 bacterial, 583 archaeal, and 36 eukaryotic microbial ribotypes were detected, respectively. A total of 22 bacterial phyla (16 formally described phyla and six candidate phyla) were recovered. Proteobacteria was the most abundant group, followed by Chloroflexi and Actinobacteria. High-abundance Rhizobiales and diverse Chloroflexi were observed in the bacterial community. The archaeal population was composed of Crenarchaeota and Euryarchaeota, with Marine Group I as the dominant lineage. In particular, Candidatus Nitrosopumilus dominated the archaeal community. Besides bacteria and archaea, the zoanthid harbored eukaryotic microorganisms including fungi and algae though their diversity was very low. This study provided the first insights into the microbial community associated with P. australiae by 454 pyrosequencing, consequently laid a basis for the understanding of the association of P. australiae-microbes symbioses.

Neurotoxin localization to ectodermal gland cells uncovers an alternative mechanism of venom delivery in sea anemones

OpenAIRE

Moran, Yehu; Genikhovich, Grigory; Gordon, Dalia; Wienkoop, Stefanie; Zenkert, Claudia; Özbek, Suat; Technau, Ulrich; Gurevitz, Michael

2011-01-01

Jellyfish, hydras, corals and sea anemones (phylum Cnidaria) are known for their venomous stinging cells, nematocytes, used for prey and defence. Here we show, however, that the potent Type I neurotoxin of the sea anemone Nematostella vectensis, Nv1, is confined to ectodermal gland cells rather than nematocytes. We demonstrate massive Nv1 secretion upon encounter with a crustacean prey. Concomitant discharge of nematocysts probably pierces the prey, expediting toxin penetration. Toxin efficie...

Chesapeake Bay Study. Supplement A. Problem Identification. Supplement B. Public Involvement. Supplement C. The Chesapeake Bay Hydraulic Model.

Science.gov (United States)

1984-09-01

Amphipod (5 genera) Canvasback Sand flea Lesser scaup Cnidaria 4’ Grass shrimp 4’ Bufflehead 4 Sand shrimp ** Osprey " Stinging nettle 4’ Xanthid crab (2...thereby decreasing the amounts of available oxygen in the water and, in extreme cases, causing fish kills. In addition, the use of insecticides in...where demands are the greatest. The stinging sea nettle and the closely related comb A-79 f. . . . . . • _ . . ... . .. jellies or ctenophores which

Evaluating hypotheses of basal animal phylogeny using complete sequences of large and small subunit rRNA

International Nuclear Information System (INIS)

Medina, Monica; Collins, Allen G.; Silberman, Jeffrey; Sogin, Mitchell L.

2001-01-01

We studied the evolutionary relationships among basal metazoan lineages by using complete large subunit (LSU) and small subunit (SSU) ribosomal RNA sequences for 23 taxa. After identifying competing hypotheses, we performed maximum likelihood searches for trees conforming to each hypothesis. Kishino-Hasegawa tests were used to determine whether the data (LSU, SSU, and combined) reject any of the competing hypotheses. We also conducted unconstrained tree searches, compared the resulting topologies, and calculated bootstrap indices. Shimodaira-Hasegawa tests were applied to determine whether the data reject any of the topologies resulting from the constrained and unconstrained tree searches. LSU, SSU, and the combined data strongly contradict two assertions pertaining to sponge phylogeny. Hexactinellid sponges are not likely to be the basal lineage of amonophyletic Porifera or the sister group to all other animals. Instead, Hexactinellida and Demospongia form a well-supported clade of siliceous sponges, Silicea. It remains unclear, on the basis of these data alone, whether the calcarean sponges are more closely related to Silicea or to nonsponge animals. The SSU and combined data reject the hypothesis that Bilateria is more closely related to Ctenophora than it is to Cnidaria, whereas LSU data alone do not refute either hypothesis. LSU and SSU data agree in supporting the monophyly of Bilateria, Cnidaria, Ctenophora, and Metazoa. LSU sequence data reveal phylogenetic structure in a data set with limited taxon sampling. Continued accumulation of LSU sequences should increase our understanding of animal phylogeny

Cubozoa e Scyphozoa (Cnidaria: Medusozoa de águas costeiras do Brasil Cubozoa and Scyphozoa (Cnidaria: Medusozoa from Brazilian coastal waters

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André C. Morandini

2005-09-01

Full Text Available As espécies de Cubozoa e Scyphozoa costeiras que ocorrem no Brasil são descritas, com base em espécimes de coleções de museus e exemplares recém-coletados. Chaves de identificação e um glossário também são apresentados. As espécies descritas são: Aurelia sp.; Cassiopea xamachana Bigelow, 1892; Chiropsalmus quadrumanus (Müller, 1859; Chrysaora lactea Eschscholtz, 1829; Drymonema dalmatinum Haeckel, 1880; Linuche unguiculata (Swartz, 1788; Lychnorhiza lucerna Haeckel, 1880; Nausithoe aurea Silveira & Morandini, 1997; Phyllorhiza punctata von Lendenfeld, 1884; Stomolophus meleagris Agassiz, 1862; Tamoya haplonema Müller, 1859 e Tripedalia cystophora Conant, 1897.Coastal species of Cubozoa and Scyphozoa occurring in Brazil are described, based on museum specimens and recently collected ones. Identification keys and a glossary are also presented. The listed species are: Aurelia sp.; Cassiopea xamachana Bigelow, 1892; Chiropsalmus quadrumanus (Müller, 1859; Chrysaora lactea Eschscholtz, 1829; Drymonema dalmatinum Haeckel, 1880; Linuche unguiculata (Swartz, 1788; Lychnorhiza lucerna Haeckel, 1880; Nausithoe aurea Silveira & Morandini, 1997; Phyllorhiza punctata von Lendenfeld, 1884; Stomolophus meleagris Agassiz, 1862; Tamoya haplonema Müller, 1859; and Tripedalia cystophora Conant, 1897.

Antimicrobial Compounds from Marine Invertebrates-Derived Microorganisms.

Science.gov (United States)

Liu, Juan; Jung, Jee H; Liu, Yonghong

2016-01-01

It is known that marine invertebrates, including sponges, tunicates, cnidaria or mollusks, host affluent and various communities of symbiotic microorganisms. The microorganisms associated with the invertebrates metabolized various biologically active compounds, which could be an important resource for the discovery and development of potentially novel drugs. In this review, the new compounds with antimicrobial activity isolated from marine invertebrate-derived microorganisms in the last decade (2004-2014) will be presented, with focus on the relevant antimicrobial activities, origin of isolation, and information of strain species. New compounds without antimicrobial activity were not revealed.

Biology and ecology of Irukandji jellyfish (Cnidaria: Cubozoa).

Science.gov (United States)

Gershwin, Lisa-ann; Richardson, Anthony J; Winkel, Kenneth D; Fenner, Peter J; Lippmann, John; Hore, Russell; Avila-Soria, Griselda; Brewer, David; Kloser, Rudy J; Steven, Andy; Condie, Scott

2013-01-01

Irukandji stings are a leading occupational health and safety issue for marine industries in tropical Australia and an emerging problem elsewhere in the Indo-Pacific and Caribbean. Their mild initial sting frequently results in debilitating illness, involving signs of sympathetic excess including excruciating pain, sweating, nausea and vomiting, hypertension and a feeling of impending doom; some cases also experience acute heart failure and pulmonary oedema. These jellyfish are typically small and nearly invisible, and their infestations are generally mysterious, making them scary to the general public, irresistible to the media, and disastrous for tourism. Research into these fascinating species has been largely driven by the medical profession and focused on treatment. Biological and ecological information is surprisingly sparse, and is scattered through grey literature or buried in dispersed publications, hampering understanding. Given that long-term climate forecasts tend toward conditions favourable to jellyfish ecology, that long-term legal forecasts tend toward increasing duty-of-care obligations, and that bioprospecting opportunities exist in the powerful Irukandji toxins, there is a clear need for information to help inform global research and robust management solutions. We synthesise and contextualise available information on Irukandji taxonomy, phylogeny, reproduction, vision, behaviour, feeding, distribution, seasonality, toxins, and safety. Despite Australia dominating the research in this area, there are probably well over 25 species worldwide that cause the syndrome and it is an understudied problem in the developing world. Major gaps in knowledge are identified for future research: our lack of clarity on the socio-economic impacts, and our need for time series and spatial surveys of the species, make this field particularly enticing. © 2013 Elsevier Ltd. All rights reserved.

Conserved intron positions in FGFR genes reflect the modular structure of FGFR and reveal stepwise addition of domains to an already complex ancestral FGFR.

Science.gov (United States)

Rebscher, Nicole; Deichmann, Christina; Sudhop, Stefanie; Fritzenwanker, Jens Holger; Green, Stephen; Hassel, Monika

2009-10-01

We have analyzed the evolution of fibroblast growth factor receptor (FGFR) tyrosine kinase genes throughout a wide range of animal phyla. No evidence for an FGFR gene was found in Porifera, but we tentatively identified an FGFR gene in the placozoan Trichoplax adhaerens. The gene encodes a protein with three immunoglobulin-like domains, a single-pass transmembrane, and a split tyrosine kinase domain. By superimposing intron positions of 20 FGFR genes from Placozoa, Cnidaria, Protostomia, and Deuterostomia over the respective protein domain structure, we identified ten ancestral introns and three conserved intron groups. Our analysis shows (1) that the position of ancestral introns correlates to the modular structure of FGFRs, (2) that the acidic domain very likely evolved in the last common ancestor of triploblasts, (3) that splicing of IgIII was enabled by a triploblast-specific insertion, and (4) that IgI is subject to substantial loss or duplication particularly in quickly evolving genomes. Moreover, intron positions in the catalytic domain of FGFRs map to the borders of protein subdomains highly conserved in other serine/threonine kinases. Nevertheless, these introns were introduced in metazoan receptor tyrosine kinases exclusively. Our data support the view that protein evolution dating back to the Cambrian explosion took place in such a short time window that only subtle changes in the domain structure are detectable in extant representatives of animal phyla. We propose that the first multidomain FGFR originated in the last common ancestor of Placozoa, Cnidaria, and Bilateria. Additional domains were introduced mainly in the ancestor of triploblasts and in the Ecdysozoa.

Catalog of taxa introduced by Luitfried Salvini-Plawen (1939-2014).

Science.gov (United States)

Affenzeller, Susanne; Steiner, Gerhard

2017-10-17

Luitfried Salvini-Plawen was one of the most distinguished researchers for molluscan phylogenetic systematics of the last decades. In his publications he described a total of 193 species: 134 Solenogastres, 34 Caudofoveata, 14 interstitial Gastropoda, one polyplacophoran and the remaining comprising Cnidaria, Priapulida, Kamptozoa, and Echinodermata. In addition, he introduced 47 genus-group names and 54 names for family-level and higher taxa. This catalog comprises lists of all taxon names published by Luitfried Salvini-Plawen. The catalog entries contain taxonomic information, original citations, type localities and type collections. It aims to facilitate further research on these and related taxa.

Gelatinous plankton is central to the diet of European eel (Anguilla anguilla) larvae in the Sargasso Sea

DEFF Research Database (Denmark)

Ayala, Daniel Jiro; Munk, Peter; Lundgreen, Regitze B. C.

2018-01-01

endangered species. Next-generation 18S rRNA gene sequencing data of Sargasso Sea eel larvae gut contents and marine snow aggregates was compared with a reference plankton database to assess the trophic relations of eel larvae. Gut contents of A. anguilla larvae were not well explained by the eukaryotic...... composition of marine snow aggregates; gut contents being dominated by gene sequences of Hydrozoa taxa (phylum Cnidaria), while snow aggregates were dominated by Crustacea taxa. Pronounced differences between gut contents and marine snow aggregates were also seen in the prokaryotic 16S rRNA gene composition...

DNA Barcoding the Medusozoa using mtCOI

Science.gov (United States)

Ortman, Brian D.; Bucklin, Ann; Pagès, Francesc; Youngbluth, Marsh

2010-12-01

The Medusozoa are a clade within the Cnidaria comprising the classes Hydrozoa, Scyphozoa, and Cubozoa. Identification of medusozoan species is challenging, even for taxonomic experts, due to their fragile forms and complex, morphologically-distinct life history stages. In this study 231 sequences for a portion of the mitochondrial Cytochrome Oxidase I (mtCOI) gene were obtained from 95 species of Medusozoans including; 84 hydrozoans (61 siphonophores, eight anthomedusae, four leptomedusae, seven trachymedusae, and four narcomedusae), 10 scyphozoans (three coronatae, four semaeostomae, two rhizostomae, and one stauromedusae), and one cubozoan. This region of mtCOI has been used as a DNA barcode (i.e., a molecular character for species recognition and discrimination) for a diverse array of taxa, including some Cnidaria. Kimura 2-parameter (K2P) genetic distances between sequence variants within species ranged from 0 to 0.057 (mean 0.013). Within the 13 genera for which multiple species were available, K2P distance between congeneric species ranged from 0.056 to 0.381. A cluster diagram generated by Neighbor Joining (NJ) using K2P distances reliably clustered all barcodes of the same species with ≥99% bootstrap support, ensuring accurate identification of species. Intra- and inter-specific variation of the mtCOI gene for the Medusozoa are appropriate for this gene to be used as a DNA barcode for species-level identification, but not for phylogenetic analysis or taxonomic classification of unknown sequences at higher taxonomic levels. This study provides a set of molecular tools that can be used to address questions of speciation, biodiversity, life-history, and population boundaries in the Medusozoa.

Broad Phylogenetic Occurrence of the Oxygen-Binding Hemerythrins in Bilaterians.

Science.gov (United States)

Costa-Paiva, Elisa M; Schrago, Carlos G; Halanych, Kenneth M

2017-10-01

Animal tissues need to be properly oxygenated for carrying out catabolic respiration and, as such, natural selection has presumably favored special molecules that can reversibly bind and transport oxygen. Hemoglobins, hemocyanins, and hemerythrins (Hrs) fulfill this role, with Hrs being the least studied. Knowledge of oxygen-binding proteins is crucial for understanding animal physiology. Hr genes are present in the three domains of life, Archaea, Bacteria, and Eukaryota; however, within Animalia, Hrs has been reported only in marine species in six phyla (Annelida, Brachiopoda, Priapulida, Bryozoa, Cnidaria, and Arthropoda). Given this observed Hr distribution, whether all metazoan Hrs share a common origin is circumspect. We investigated Hr diversity and evolution in metazoans, by employing in silico approaches to survey for Hrs from of 120 metazoan transcriptomes and genomes. We found 58 candidate Hr genes actively transcribed in 36 species distributed in 11 animal phyla, with new records in Echinodermata, Hemichordata, Mollusca, Nemertea, Phoronida, and Platyhelminthes. Moreover, we found that "Hrs" reported from Cnidaria and Arthropoda were not consistent with that of other metazoan Hrs. Contrary to previous suggestions that Hr genes were absent in deuterostomes, we find Hr genes present in deuterostomes and were likely present in early bilaterians, but not in nonbilaterian animal lineages. As expected, the Hr gene tree did not mirror metazoan phylogeny, suggesting that Hrs evolutionary history was complex and besides the oxygen carrying capacity, the drivers of Hr evolution may also consist of secondary functional specializations of the proteins, like immunological functions. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

The diet of cubomedusae (cnidaria, cubozoa in southern Brazil

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Miodeli Nogueira Júnior

2008-09-01

Full Text Available The diet of cubomedusae Tamoya haplonema Müller, 1859 (Carybdeidae and Chiropsalmus quadrumanus (Müller, 1859 (Chirodropidae was examined in specimens collected on the Southern Brazilian coast (25º20' - 25º55'S; 48º10' - 48º35'W, between December 1998 and December 2004. This is the first study to analyze this biological aspect in cubomedusae from the South Atlantic. The gastrovascular cavities of most (55%; n = 29 specimens of T. haplonema were empty while the remainder had teleosteans parts such as scales, vertebrae and otoliths. In C. quadrumanus (n = 726, the most important items were the pelagic sergestid shrimp Peisos petrunkevitchi Burkenroad, 1945 and Brachyura larvae, mainly megalops. Small crabs, isopods, fish, fish eggs and nematodes were less common. A dietary shift was clearly observed during C. quadrumanus growth. Smaller individuals consumed a greater variety of prey, mostly Brachyura larvae, and they also had higher frequencies of empty stomachs. As their size increased, megalopas decreased and P. petrunkevitchi became the most important item in their diet.A dieta das cubomedusas Tamoya haplonema Müller, 1859 (Carybdeidae e Chiropsalmus quadrumanus (Müller, 1859 (Chirodropidae foi analisada em espécimes coletados no litoral do Paraná (25º20' - 25º55'S; 48º10' - 48º35'W, sul do Brasil, entre dezembro de 1998 e dezembro de 2004, e é o primeiro estudo a abordar este aspecto da biologia de Cubozoa no Atlântico Sul. A cavidade gastrovascular da maioria (55% dos 29 exemplares de T. haplonema mostrou-se vazia, e dos demais continha partes corporais de peixes teleósteos, como escamas, vértebras e otólitos. Em 726 exemplares de C. quadrumanus os itens alimentares mais importantes foram o camarão sergestídeo Peisos petrunkevitchi Burkenroad, 1945 e larvas de Brachyura, principalmente megalopas. Pequenos caranguejos, isópodes, peixes, ovos de peixes e nematóides foram menos comuns. Mudanças na dieta evidenciaram-se durante o crescimento de C. quadrumanus. Indivíduos menores alimentaram-se de maior variedade de presas, principalmente de larvas de Brachyura, e também apresentaram freqüência mais alta de estômagos vazios. À medida que cresciam, a ingestão de larvas diminuía de importância enquanto a do camarão P. petrunkevitchi aumentava, até este se tornar o principal item na dieta da espécie.

Review on hard coral recruitment (Cnidaria: Scleractinia in Colombia

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Luisa F. Dueñas

2011-12-01

Full Text Available Recruitment, defined and measured as the incorporation of new individuals (i.e. coral juveniles into a population, is a fundamentalprocess for ecologists, evolutionists and conservationists due to its direct effect on population structure and function. Because most coralpopulations are self-feeding, a breakdown in recruitment would lead to local extinction. Recruitment indirectly affects both renewal andmaintenance of existing and future coral communities, coral reef biodiversity (bottom-up effect and therefore coral reef resilience. This process has been used as an indirect measure of individual reproductive success (fitness and is the final stage of larval dispersal leading to population connectivity. As a result, recruitment has been proposed as an indicator of coral-reef health in marine protected areas, as well as a central aspect of the decision-making process concerning management and conservation. The creation of management plans to promote impact mitigation, rehabilitation and conservation of the Colombian coral reefs is a necessity that requires firstly, a review and integration of existing literature on scleractinian coral recruitment in Colombia and secondly, larger scale field studies. This motivated us to summarize and analyze all existing information on coral recruitment to determine the state of knowledge, isolate patterns, identify gaps, and suggest future lines of research.

Potential of DNA sequences to identify zoanthids (Cnidaria: Zoantharia).

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Sinniger, Frederic; Reimer, James D; Pawlowski, Jan

2008-12-01

The order Zoantharia is known for its chaotic taxonomy and difficult morphological identification. One method that potentially could help for examining such troublesome taxa is DNA barcoding, which identifies species using standard molecular markers. The mitochondrial cytochrome oxidase subunit I (COI) has been utilized to great success in groups such as birds and insects; however, its applicability in many other groups is controversial. Recently, some studies have suggested that barcoding is not applicable to anthozoans. Here, we examine the use of COI and mitochondrial 16S ribosomal DNA for zoanthid identification. Despite the absence of a clear barcoding gap, our results show that for most of 54 zoanthid samples, both markers could separate samples to the species, or species group, level, particularly when easily accessible ecological or distributional data were included. Additionally, we have used the short V5 region of mt 16S rDNA to identify eight old (13 to 50 years old) museum samples. We discuss advantages and disadvantages of COI and mt 16S rDNA as barcodes for Zoantharia, and recommend that either one or both of these markers be considered for zoanthid identification in the future.

Interannual abundance changes of gelatinous carnivore zooplankton unveil climate-driven hydrographic variations in the Iberian Peninsula, Portugal.

Science.gov (United States)

D'Ambrosio, Mariaelena; Molinero, Juan C; Azeiteiro, Ulisses M; Pardal, Miguel A; Primo, Ana L; Nyitrai, Daniel; Marques, Sónia C

2016-09-01

The persistent massive blooms of gelatinous zooplankton recorded during recent decades may be indicative of marine ecosystem changes. In this study, we investigated the potential influence of the North Atlantic climate (NAO) variability on decadal abundance changes of gelatinous carnivore zooplankton in the Mondego estuary, Portugal, over the period 2003-2013. During the 11-year study, the community of gelatinous carnivores encompassed a larger diversity of hydromedusae than siphonophores; the former dominated by Obelia spp., Lizzia blondina, Clythia hemisphaerica, Liriope tetraphylla and Solmaris corona, while the latter dominated by Muggiaea atlantica. Gelatinous carnivore zooplankton displayed marked interannual variability and mounting species richness over the period examined. Their pattern of abundance shifted towards larger abundances ca. 2007 and significant phenological changes. The latter included a shift in the mean annual pattern (from unimodal to bimodal peak, prior and after 2007 respectively) and an earlier timing of the first annual peak concurrent with enhanced temperatures. These changes were concurrent with the climate-driven environmental variability mainly controlled by the NAO, which displayed larger variance after 2007 along with an enhanced upwelling activity. Structural equation modelling allowed depicting cascading effects derived from the NAO influence on regional climate and upwelling variability further shaping water temperature. Such cascading effect percolated the structure and dynamics of the community of gelatinous carnivore zooplankton in the Mondego estuary. Copyright © 2016 Elsevier Ltd. All rights reserved.

On the origins of arrestin and rhodopsin

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Alvarez Carlos E

2008-07-01

Full Text Available Abstract Background G protein coupled receptors (GPCRs are the most numerous proteins in mammalian genomes, and the most common targets of clinical drugs. However, their evolution remains enigmatic. GPCRs are intimately associated with trimeric G proteins, G protein receptor kinases, and arrestins. We conducted phylogenetic studies to reconstruct the history of arrestins. Those findings, in turn, led us to investigate the origin of the photosensory GPCR rhodopsin. Results We found that the arrestin clan is comprised of the Spo0M protein family in archaea and bacteria, and the arrestin and Vps26 families in eukaryotes. The previously known animal arrestins are members of the visual/beta subfamily, which branched from the founding "alpha" arrestins relatively recently. Curiously, we identified both the oldest visual/beta arrestin and opsin genes in Cnidaria (but not in sponges. The arrestin clan has 14 human members: 6 alphas, 4 visual/betas, and 4 Vps26 genes. Others recently showed that the 3D structure of mammalian Vps26 and the biochemical function of the yeast alpha arrestin PalF are similar to those of beta arrestins. We note that only alpha arrestins have PY motifs (known to bind WW domains in their C-terminal tails, and only visual/betas have helix I in the Arrestin N domain. Conclusion We identified ciliary opsins in Cnidaria and propose this subfamily is ancestral to all previously known animal opsins. That finding is consistent with Darwin's theory that eyes evolved once, and lends some support to Parker's hypothesis that vision triggered the Cambrian explosion of life forms. Our arrestin findings have implications on the evolution of GPCR signaling, and on the biological roles of human alpha arrestins.

Trends in the Discovery of New Marine Natural Products from Invertebrates over the Last Two Decades – Where and What Are We Bioprospecting?

Science.gov (United States)

Leal, Miguel Costa; Puga, João; Serôdio, João; Gomes, Newton C. M.; Calado, Ricardo

2012-01-01

It is acknowledged that marine invertebrates produce bioactive natural products that may be useful for developing new drugs. By exploring untapped geographical sources and/or novel groups of organisms one can maximize the search for new marine drugs to treat human diseases. The goal of this paper is to analyse the trends associated with the discovery of new marine natural products from invertebrates (NMNPI) over the last two decades. The analysis considers different taxonomical levels and geographical approaches of bioprospected species. Additionally, this research is also directed to provide new insights into less bioprospected taxa and world regions. In order to gather the information available on NMNPI, the yearly-published reviews of Marine Natural Products covering 1990–2009 were surveyed. Information on source organisms, specifically taxonomical information and collection sites, was assembled together with additional geographical information collected from the articles originally describing the new natural product. Almost 10000 NMNPI were discovered since 1990, with a pronounced increase between decades. Porifera and Cnidaria were the two dominant sources of NMNPI worldwide. The exception was polar regions where Echinodermata dominated. The majority of species that yielded the new natural products belong to only one class of each Porifera and Cnidaria phyla (Demospongiae and Anthozoa, respectively). Increased bioprospecting efforts were observed in the Pacific Ocean, particularly in Asian countries that are associated with the Japan Biodiversity Hotspot and the Kuroshio Current. Although results show comparably less NMNPI from polar regions, the number of new natural products per species is similar to that recorded for other regions. The present study provides information to future bioprospecting efforts addressing previously unexplored taxonomic groups and/or regions. We also highlight how marine invertebrates, which in some cases have no commercial value

Conservation and diversification of Msx protein in metazoan evolution.

Science.gov (United States)

Takahashi, Hirokazu; Kamiya, Akiko; Ishiguro, Akira; Suzuki, Atsushi C; Saitou, Naruya; Toyoda, Atsushi; Aruga, Jun

2008-01-01

Msx (/msh) family genes encode homeodomain (HD) proteins that control ontogeny in many animal species. We compared the structures of Msx genes from a wide range of Metazoa (Porifera, Cnidaria, Nematoda, Arthropoda, Tardigrada, Platyhelminthes, Mollusca, Brachiopoda, Annelida, Echiura, Echinodermata, Hemichordata, and Chordata) to gain an understanding of the role of these genes in phylogeny. Exon-intron boundary analysis suggested that the position of the intron located N-terminally to the HDs was widely conserved in all the genes examined, including those of cnidarians. Amino acid (aa) sequence comparison revealed 3 new evolutionarily conserved domains, as well as very strong conservation of the HDs. Two of the three domains were associated with Groucho-like protein binding in both a vertebrate and a cnidarian Msx homolog, suggesting that the interaction between Groucho-like proteins and Msx proteins was established in eumetazoan ancestors. Pairwise comparison among the collected HDs and their C-flanking aa sequences revealed that the degree of sequence conservation varied depending on the animal taxa from which the sequences were derived. Highly conserved Msx genes were identified in the Vertebrata, Cephalochordata, Hemichordata, Echinodermata, Mollusca, Brachiopoda, and Anthozoa. The wide distribution of the conserved sequences in the animal phylogenetic tree suggested that metazoan ancestors had already acquired a set of conserved domains of the current Msx family genes. Interestingly, although strongly conserved sequences were recovered from the Vertebrata, Cephalochordata, and Anthozoa, the sequences from the Urochordata and Hydrozoa showed weak conservation. Because the Vertebrata-Cephalochordata-Urochordata and Anthozoa-Hydrozoa represent sister groups in the Chordata and Cnidaria, respectively, Msx sequence diversification may have occurred differentially in the course of evolution. We speculate that selective loss of the conserved domains in Msx family

Some Actiniaria (Cnidaria: Anthozoa) from the west coast of India

Digital Repository Service at National Institute of Oceanography (India)

Hartog, J. C. Den; Jayasree, V.

A small collection of five species of Actiniaria from the west coast of India, including three new species, is described and discussed. It concerns Anthopleura anjunae spec. nov., Bunodosoma goanensis spec. nov., Synantheopsis parulekari spec. nov...

Biological activities of secondary metabolites of the order Zoanthids

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Zahra Aminikhoei

2015-11-01

Full Text Available The phylum Cnidaria is a large, diverse and ecologically important group of marine invertebrates, which produce powerful toxins and venoms. The number of marine natural product from cnidarians isolated from class Anthozoa. Among the Anthozoa, the order of zoanthids are sessile, clonal and mostly brightly colored invertebrate which produce high biodiversity of cytolitic, neurotoxic and cardiotoxic compounds. Zoanthids containing palytoxins are reportedly among the most toxic marine organisms known. In addition, a high concentration of zoanthamine alkaloids extracted from this group.The zoanthamine alkaloids were isolated over 20 years ago, exhibit a broad range of biological activities.The best studied and most well-known biological activity of zoanthamine derivative significantly suppressed bone resorption and enhanced bone formation.

Two new species of Neozoanthus (Cnidaria, Hexacorallia, Zoantharia from the Pacific

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James Reimer

2012-11-01

Full Text Available The zoanthid genus Neozoanthus was originally described in 1972 from a single species in Madagascar. This monotypic genus was placed within its own family, Neozoanthidae, given its unusual characters of only partial sand encrustation, and an endodermal sphincter muscle combined with a brachycnemic mesenterial arrangement. Recently, undescribed specimens of Neozoanthus were discovered thousands of kilometers away in both Australia and Japan. While the phylogenetic and evolutionary aspects of Neozoanthus spp. are now somewhat well understood, the new specimens remained undescribed. Here we describe the specimens as two new species, N. uchina sp. n. from the Middle Ryukyu Islands of southern Japan, and N. caleyi sp. n. from the waters around Heron Island, on the Great Barrier Reef in Australia. Both species can be distinguished from each other and the type species, N. tulearensis, by their distributions, oral disk colors, and average numbers of tentacles. Additionally, each species appears to have subtle differences in their cnidae. The division of Japanese and Australian specimens into two species is strongly supported by recently reported phylogenetic data. The discovery and description of these two species highlights how little is known of zoanthid species diversity in the Indo-Pacific.

DNA extraction from sea anemone (Cnidaria: Actiniaria tissues for molecular analyses

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Pinto S.M.

2000-01-01

Full Text Available A specific DNA extraction method for sea anemones is described in which extraction of total DNA from eight species of sea anemones and one species of corallimorpharian was achieved by changing the standard extraction protocols. DNA extraction from sea anemone tissue is made more difficult both by the tissue consistency and the presence of symbiotic zooxanthellae. The technique described here is an efficient way to avoid problems of DNA contamination and obtain large amounts of purified and integral DNA which can be used in different kinds of molecular analyses.

Taxonomic classification of the reef coral family Lobophylliidae (Cnidaria: Anthozoa: Scleractinia)

KAUST Repository

Huang, Danwei; Arrigoni, Roberto; Benzoni, Francesca; Fukami, Hironobu; Knowlton, Nancy; Smith, Nathan D.; Stolarski, Jarosław; Chou, Loke Ming; Budd, Ann F.

2016-01-01

Lobophylliidae is a family-level clade of corals within the ‘robust’ lineage of Scleractinia. It comprises species traditionally classified as Indo-Pacific ‘mussids’, ‘faviids’, and ‘pectiniids’. Following detailed revisions of the closely related families Merulinidae, Mussidae, Montastraeidae, and Diploastraeidae, this monograph focuses on the taxonomy of Lobophylliidae. Specifically, we studied 44 of a total of 54 living lobophylliid species from all 11 genera based on an integrative analysis of colony, corallite, and subcorallite morphology with molecular sequence data. By examining coral skeletal features at three distinct levels – macromorphology, micromorphology, and microstructure – we built a morphological matrix comprising 46 characters. Data were analysed via maximum parsimony and transformed onto a robust molecular phylogeny inferred using two nuclear (histone H3 and internal transcribed spacers) and one mitochondrial (cytochrome c oxidase subunit I) DNA loci. The results suggest that micromorphological characters exhibit the lowest level of homoplasy within Lobophylliidae. Molecular and morphological trees show that Symphyllia, Parascolymia, and Australomussa should be considered junior synonyms of Lobophyllia, whereas Lobophyllia pachysepta needs to be transferred to Acanthastrea. Our analyses also lend strong support to recent revisions of Acanthastrea, which has been reorganized into five separate genera (Lobophyllia, Acanthastrea, Homophyllia, Sclerophyllia, and Micromussa), and to the establishment of Australophyllia. Cynarina and the monotypic Moseleya remain unchanged, and there are insufficient data to redefine Oxypora, Echinophyllia, and Echinomorpha. Finally, all lobophylliid genera are diagnosed under the phylogenetic classification system proposed here, which will facilitate the placement of extinct taxa on the scleractinian tree of life.

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

Taxonomic classification of the reef coral family Lobophylliidae (Cnidaria: Anthozoa: Scleractinia)

KAUST Repository

Huang, Danwei

2016-10-14

Lobophylliidae is a family-level clade of corals within the ‘robust’ lineage of Scleractinia. It comprises species traditionally classified as Indo-Pacific ‘mussids’, ‘faviids’, and ‘pectiniids’. Following detailed revisions of the closely related families Merulinidae, Mussidae, Montastraeidae, and Diploastraeidae, this monograph focuses on the taxonomy of Lobophylliidae. Specifically, we studied 44 of a total of 54 living lobophylliid species from all 11 genera based on an integrative analysis of colony, corallite, and subcorallite morphology with molecular sequence data. By examining coral skeletal features at three distinct levels – macromorphology, micromorphology, and microstructure – we built a morphological matrix comprising 46 characters. Data were analysed via maximum parsimony and transformed onto a robust molecular phylogeny inferred using two nuclear (histone H3 and internal transcribed spacers) and one mitochondrial (cytochrome c oxidase subunit I) DNA loci. The results suggest that micromorphological characters exhibit the lowest level of homoplasy within Lobophylliidae. Molecular and morphological trees show that Symphyllia, Parascolymia, and Australomussa should be considered junior synonyms of Lobophyllia, whereas Lobophyllia pachysepta needs to be transferred to Acanthastrea. Our analyses also lend strong support to recent revisions of Acanthastrea, which has been reorganized into five separate genera (Lobophyllia, Acanthastrea, Homophyllia, Sclerophyllia, and Micromussa), and to the establishment of Australophyllia. Cynarina and the monotypic Moseleya remain unchanged, and there are insufficient data to redefine Oxypora, Echinophyllia, and Echinomorpha. Finally, all lobophylliid genera are diagnosed under the phylogenetic classification system proposed here, which will facilitate the placement of extinct taxa on the scleractinian tree of life.

Species Diversity of Shallow Water Zoanthids (Cnidaria: Anthozoa: Hexacorallia in Florida

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James Davis Reimer

2012-01-01

Full Text Available Shallow water zooxanthellate zoanthids are a common component of the coral reef ecosystems of the Caribbean. Despite this, their species diversity remains poorly understood. In this study, collected Palythoa, Zoanthus, Isaurus, and Terrazoanthus specimens from the waters of Florida were phylogenetically examined to obtain a better understanding of zoanthid species diversity in the Caribbean. Surprisingly, the results from analyses utilizing three DNA markers (mitochondrial 16S ribosomal DNA, cytochrome oxidase subunit I, and the internal transcribed spacer of ribosomal DNA showed the presence of at least eleven species, of which up to four appear undescribed. Additionally, the presence of the genus Terrazoanthus in the Caribbean was confirmed for the first time. Attempts to match phylogenetic species or clades with original literature were hampered by vague and short original descriptions, and it is clear that for Atlantic Palythoa and Zoanthus species an in-depth and multidisciplinary investigation is needed to reconcile recent phylogenetic results such as in this study with traditional taxonomy. Furthermore, most shallow water zoanthid species from Florida were observed to have close, sister-species relationships with previously investigated species in the Pacific Ocean. These results indicate that many brachycnemic zoanthid species likely had a Caribbean-Pacific distribution until the formation of the Isthmus of Panama. However, due to inadvertent redescriptions, overall species diversity in these two common genera is likely much lower than literature indicates.

Species Diversity of Shallow Water Zoanthids (Cnidaria: Anthozoa: Hexacorallia) in Florida

OpenAIRE

Reimer, James Davis; Foord, Colin; Irei, Yuka

2012-01-01

Shallow water zooxanthellate zoanthids are a common component of the coral reef ecosystems of the Caribbean. Despite this, their species diversity remains poorly understood. In this study, collected Palythoa, Zoanthus, Isaurus, and Terrazoanthus specimens from the waters of Florida were phylogenetically examined to obtain a better understanding of zoanthid species diversity in the Caribbean. Surprisingly, the results from analyses utilizing three DNA markers (mitochondrial 16S ribosomal DNA, ...

Two new species of Neozoanthus (Cnidaria, Hexacorallia, Zoantharia) from the Pacific

Science.gov (United States)

Reimer, James Davis; Irei, Yuka; Fujii, Takuma

2012-01-01

Abstract The zoanthid genus Neozoanthus was originally described in 1972 from a single species in Madagascar. This monotypic genus was placed within its own family, Neozoanthidae, given its unusual characters of only partial sand encrustation, and an endodermal sphincter muscle combined with a brachycnemic mesenterial arrangement. Recently, undescribed specimens of Neozoanthus were discovered thousands of kilometers away in both Australia and Japan. While the phylogenetic and evolutionary aspects of Neozoanthus spp. are now somewhat well understood, the new specimens remained undescribed. Here we describe the specimens as two new species, Neozoanthus uchina sp. n. from the Middle Ryukyu Islands of southern Japan, and Neozoanthus caleyi sp. n. from the waters around Heron Island, on the Great Barrier Reef in Australia. Both species can be distinguished from each other and the type species, Neozoanthus tulearensis, by their distributions, oral disk colors, and average numbers of tentacles. Additionally, each species appears to have subtle differences in their cnidae. The division of Japanese and Australian specimens into two species is strongly supported by recently reported phylogenetic data. The discovery and description of these two species highlights how little is known of zoanthid species diversity in the Indo-Pacific. PMID:23275752

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.

T-box and homeobox genes from the ctenophore Pleurobrachia pileus: comparison of Brachyury, Tbx2/3 and Tlx in basal metazoans and bilaterians.

Science.gov (United States)

Martinelli, Cosimo; Spring, Jürg

2005-09-12

Most animals are classified as Bilateria and only four phyla are still extant as outgroups, namely Porifera, Placozoa, Cnidaria and Ctenophora. These non-bilaterians were not considered to have a mesoderm and hence mesoderm-specific genes. However, the T-box gene Brachyury could be isolated from sponges, placozoans and cnidarians. Here, we describe the first Brachyury and a Tbx2/3 homologue from a ctenophore. In addition, analysing T-box and homeobox genes under comparable conditions in all four basal phyla lead to the discovery of novel T-box genes in sponges and cnidarians and a Tlx homeobox gene in the ctenophore Pleurobrachia pileus. The conservation of the T-box and the homeobox genes suggest that distinct subfamilies with different roles in bilaterians were already split in non-bilaterians.

Adult and offspring size in the ocean over 17 orders of magnitude follows two life history strategies

DEFF Research Database (Denmark)

Neuheimer, Anna; Hartvig, Martin; Heuschele, Jan

2015-01-01

is observed along with variability in physical and biological forcing factors in space and time. We compiled adult and offspring size for 407 pelagic marine species covering more than 17 orders of magnitude in body mass including Cephalopoda, Cnidaria, Crustaceans, Ctenophora, Elasmobranchii, Mammalia...... discuss where these two strategies occur and how these patterns (along with the relative size of the offspring) may be shaped by physical and biological constraints in the organism’s environment. This adaptive environment along with the evolutionary history of the different groups shape observed life......Explaining variability in offspring vs. adult size among groups is a necessary step to determine the evolutionary and environmental constraints shaping variability in life history strategies. This is of particular interest for life in the ocean where a diversity of offspring development strategies...

Severe Toxic Skin Reaction Caused by a Common Anemone and Identification of the Culprit Organism.

Science.gov (United States)

Tezcan, Özgür Deniz; Gözer, Özgür

2015-01-01

In a marine envenomation, identification of the culprit organism can be difficult. In this case report, we present our method to identify snakelocks anemone (Anemonia viridis or formerly Anemonia sulcata) as the culprit of a severe toxic skin reaction. A. viridis is one of the most common anemones of the Mediterranean Sea and the North Atlantic Ocean. It lives at a depth of up to 10 m. It is a member of the phylum Cnidaria, which includes jellyfish, anemones, hydroids, and corals. They have toxic organelles called cnidocysts that have the capacity to inject venom with microscopic harpoon-like structures. The cnidocysts of A. viridis may cause toxic and allergic reactions, and although its venom is one of the most studied cnidarian venoms, detailed case reports are rare. © 2015 International Society of Travel Medicine.

PSP toxin levels and plankton community composition and abundance in size-fractionated vertical profiles during spring/summer blooms of the toxic dinoflagellate Alexandrium fundyense in the Gulf of Maine and on Georges Bank, 2007, 2008, and 2010: 2. Plankton community composition and abundance.

Science.gov (United States)

Petitpas, Christian M; Turner, Jefferson T; Deeds, Jonathan R; Keafer, Bruce A; McGillicuddy, Dennis J; Milligan, Peter J; Shue, Vangie; White, Kevin D; Anderson, Donald M

2014-05-01

As part of the Gulf of Maine Toxicity (GOMTOX) project, we determined Alexandrium fundyense abundance, paralytic shellfish poisoning (PSP) toxin levels in various plankton size fractions, and the community composition of potential grazers of A. fundyense in plankton size fractions during blooms of this toxic dinoflagellate in the coastal Gulf of Maine and on Georges Bank in spring and summer of 2007, 2008, and 2010. PSP toxins and A. fundyense cells were found throughout the sampled water column (down to 50 m) in the 20-64 μm size fractions. While PSP toxins were widespread throughout all size classes of the zooplankton grazing community, the majority of the toxin was measured in the 20-64 μm size fraction. A. fundyense cellular toxin content estimated from field samples was significantly higher in the coastal Gulf of Maine than on Georges Bank. Most samples containing PSP toxins in the present study had diverse assemblages of grazers. However, some samples clearly suggested PSP toxin accumulation in several different grazer taxa including tintinnids, heterotrophic dinoflagellates of the genus Protoperidinium , barnacle nauplii, the harpacticoid copepod Microsetella norvegica , the calanoid copepods Calanus finmarchicus and Pseudocalanus spp., the marine cladoceran Evadne nordmanni , and hydroids of the genus Clytia . Thus, a diverse assemblage of zooplankton grazers accumulated PSP toxins through food-web interactions. This raises the question of whether PSP toxins pose a potential human health risk not only from nearshore bivalve shellfish, but also potentially from fish and other upper-level consumers in zooplankton-based pelagic food webs.

Alleged cnidarian Sphenothallus in the Late Ordovician of Baltica, its mineral composition and microstructure

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Olev Vinn

2015-12-01

Full Text Available Sphenothallus is a problematic fossil with possible cnidarian affinities. Two species of Sphenothallus, S. aff. longissimus and S. kukersianus, occur in the normal marine sediments of the Late Ordovician of Estonia. S. longissimus is more common than S. kukersianus and has a range from early Sandbian to middle Katian. Sphenothallus had a wide paleo-biogeographic distribution in the Late Ordovician. The tubes of Sphenothallus are composed of lamellae with a homo-geneous microstructure. The homogeneous microstructure could represent a diagenetic fabric, based on the similarity to diagenetic structures in Torellella (Cnidaria?, Hyolithelminthes. Tubes of Sphenothallus have an apatitic composition, but one tube contains lamellae of diagenetic calcite within the apatitic structure. Sphenothallus presumably had origi-nally biomineralized apatitic tubes. Different lattice parameters of the apatite indicate that biomineralization systems of phosphatic cnidarians Sphenothallus and Conularia sp. may have been different.

The relationship between gorgonian coral (Cnidaria: Gorgonacea) diseases and African dust storms

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Weir-Brush, J. R.; Garrison, V.H.; Smith, G.W.; Shinn, E.A.

2004-01-01

The number of reports of coral diseases has increased throughout the world in the last 20 years. Aspergillosis, which primarily affects Gorgonia ventalina and G. flabellum, is one of the few diseases to be characterized. This disease is caused by Aspergillus sydowii, a terrestrial fungus with a worldwide distribution. Upon infection, colonies may lose tissue, and ultimately, mortality may occur if the infection is not sequestered. The spores of A. sydowii are African dust storms transport and deposit pathogens, we collected air samples from both dust storms and periods of nondust in St. John, U.S. Virgin Islands. Because we focused on fungal pathogens and used A. sydowii as a model, we isolated and cultured fungi on various types of media. Fungi including Aspergillus spp. were isolated from air samples taken from dust events and non-dust events. Twenty-three separate cultures and seven genera were isolated from dust event samples whereas eight cultures from five genera were isolated from non-dust air samples. Three isolates from the Virgin Islands dust event samples morphologically identified as Aspergillus spp. produced signs of aspergillosis in seafans, and the original pathogens were re-isolated from those diseased seafans fulfilling Koch's Postulates. This research supports the hypothesis that African dust storms transport across the Atlantic Ocean and deposit potential coral pathogens in the Caribbean.

Influence of Palythoa caribaeorum (Anthozoa, Cnidaria zonation on site-attached reef fishes

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José P. Mendonça-Neto

2008-09-01

Full Text Available This work aimed to test the influence of Palythoa caribeorum, a widely distributed zoanthid in the Atlantic, on site-attached reef fish in a subtropical rocky shore. Density, richness and vertical distribution of reef fish inside (ID and outside (OD previously chosen P. caribaeorum dominance patches were compared through stationary visual censuses along three different periods. Fishes were grouped in different trophic guilds to evidence differences in resources uses in both treatments. A complexity index was estimated by the chain link method and percentage covering of benthic organisms was obtained analyzing random points from replicated photo-quadrats. We observed thirty-eight species of fishes, belonging to twenty-five families. Reef fish communities between studied patches were similar,both in terms of species composition and vertical distribution. Considering only the most site-attached fishes, which were the most frequent and abundant species, data showed that ID sustains higher diversity and abundance than OD. Results showed that benthic composition differ significantly among patches whereas complexity remained without differences. Otherwise, results indicated that these areas might play an important role in space limitation, structuring neighboring benthic community and consequently reef fish assemblages.Este estudo visou testar a influência de Palythoa caribeorum, um zoantídeo amplamente distribuído no Atlântico, na estruturação da comunidade de peixes recifais associados a um costão rochoso de uma região subtropical. A densidade, a riqueza e a distribuição vertical de peixes recifais em áreas previamente selecionadas com e sem a dominância de Palythoa caribaeorum foram comparadas através de censos visuais estacionários em três períodos distintos de tempo. Os peixes foram agrupados em guildas tróficas a fim de evidenciar diferenças nos usos dos recursos nas diferentes áreas analisadas. Foram analisados também índices de complexidade estrutural através do método da corrente e os percentuais de cobertura bentônica através de fotos quadracts replicados. Foram registradas trinta e oito espécies de peixes recifais de vinte e cinco famílias diferentes. Acomunidade de peixes entre as áreas estudadas foi similar tanto em composição de espécies quanto em distribuição vertical. Considerando apenas as espécies mais associadas ao substrato, que foram as mais freqüentes e abundantes, os dados mostraram que as áreas com dominância de P. caribaeorum sustentam maior diversidade e abundância do que as áreas sem a dominância de P. caribaeorum. Foram encontradas ainda diferenças significativas na composição bentônica entre os diferentes tratamentos estudados, mas não foram verificadas diferenças entre a complexidade estrutural entre estas áreas. No entanto, os resultados sugerem que as áreas com dominância de P. caribaeorum podem desempenhar papel importante na limitação de espaços, estruturando as comunidades bentônicas e, conseqüentemente, afetando a comunidade de peixes recifais.

Types and originals of fossil Porifera and Cnidaria of Indonesia in Naturalis

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Leloux, J.; Renema, W.

2007-01-01

The collection of Naturalis contains a significant collection of fossil corals and sponges. Within the framework of the 'NWO Groot' digitalisation projects the typespecimens, mainly from Indonesia, of Gerth, Umbgrove and related researchers were catalogued. 3920 lots containing 3479 typespecimens

Structure of the red fluorescent protein from a lancelet (Branchiostoma lanceolatum): a novel GYG chromophore covalently bound to a nearby tyrosine

Energy Technology Data Exchange (ETDEWEB)

Pletnev, Vladimir Z., E-mail: vzpletnev@gmail.com; Pletneva, Nadya V.; Lukyanov, Konstantin A.; Souslova, Ekaterina A.; Fradkov, Arkady F.; Chudakov, Dmitry M.; Chepurnykh, Tatyana; Yampolsky, Ilia V. [Russian Academy of Sciences, Moscow (Russian Federation); Wlodawer, Alexander [National Cancer Institute, Frederick, MD 21702 (United States); Dauter, Zbigniew [National Cancer Institute, Argonne, IL 60439 (United States); Pletnev, Sergei, E-mail: vzpletnev@gmail.com [National Cancer Institute, Argonne, IL 60439 (United States); SAIC-Frederick, Argonne, IL 60439 (United States); Russian Academy of Sciences, Moscow (Russian Federation)

2013-09-01

The crystal structure of the novel red emitting fluorescent protein from lancelet Branchiostoma lanceolatum (Chordata) revealed an unusual five residues cyclic unit comprising Gly58-Tyr59-Gly60 chromophore, the following Phe61 and Tyr62 covalently bound to chromophore Tyr59. A key property of proteins of the green fluorescent protein (GFP) family is their ability to form a chromophore group by post-translational modifications of internal amino acids, e.g. Ser65-Tyr66-Gly67 in GFP from the jellyfish Aequorea victoria (Cnidaria). Numerous structural studies have demonstrated that the green GFP-like chromophore represents the ‘core’ structure, which can be extended in red-shifted proteins owing to modifications of the protein backbone at the first chromophore-forming position. Here, the three-dimensional structures of green laGFP (λ{sub ex}/λ{sub em} = 502/511 nm) and red laRFP (λ{sub ex}/λ{sub em} ≃ 521/592 nm), which are fluorescent proteins (FPs) from the lancelet Branchiostoma lanceolatum (Chordata), were determined together with the structure of a red variant laRFP-ΔS83 (deletion of Ser83) with improved folding. Lancelet FPs are evolutionarily distant and share only ∼20% sequence identity with cnidarian FPs, which have been extensively characterized and widely used as genetically encoded probes. The structure of red-emitting laRFP revealed three exceptional features that have not been observed in wild-type fluorescent proteins from Cnidaria reported to date: (i) an unusual chromophore-forming sequence Gly58-Tyr59-Gly60, (ii) the presence of Gln211 at the position of the conserved catalytic Glu (Glu222 in Aequorea GFP), which proved to be crucial for chromophore formation, and (iii) the absence of modifications typical of known red chromophores and the presence of an extremely unusual covalent bond between the Tyr59 C{sup β} atom and the hydroxyl of the proximal Tyr62. The impact of this covalent bond on the red emission and the large Stokes shift (�

Mechanisms for eco-immunity in a changing enviroment: how does the coral innate immune system contend with climate change?

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Traylor-Knowles, N. G.

2016-02-01

Innate immunity plays a central role in maintaining homeostasis, and within the context of impending climate change scenarios, understanding how this system works is critical. However, the actual mechanisms involved in the evolution of the innate immune system are largely unknown. Cnidaria (including corals, sea anemones and jellyfish) are well suited for studying the fundamental functions of innate immunity because they share a common ancestor with bilaterians. This study will highlight the transcriptomic changes during a heat shock in the coral Acropora hyacinthus of American Samoa, examining the temporal changes, every half an hour for 5 hours. We hypothesize that genes involved in innate immunity, and extracellular matrix maintenance will be key components to the heat stress response. This presentation will highlight the novel role of the tumor necrosis factor receptor gene family as a responder to heat stress and present future directions for this developing field in coral reef research.

Gluconeogenesis: An ancient biochemical pathway with a new twist.

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Miyamoto, Tetsuya; Amrein, Hubert

2017-07-03

Synthesis of sugars from simple carbon sources is critical for survival of animals under limited nutrient availability. Thus, sugar-synthesizing enzymes should be present across the entire metazoan spectrum. Here, we explore the evolution of glucose and trehalose synthesis using a phylogenetic analysis of enzymes specific for the two pathways. Our analysis reveals that the production of trehalose is the more ancestral biochemical process, found in single cell organisms and primitive metazoans, but also in insects. The gluconeogenic-specific enzyme glucose-6-phosphatase (G6Pase) first appears in Cnidaria, but is also present in Echinodermata, Mollusca and Vertebrata. Intriguingly, some species of nematodes and arthropods possess the genes for both pathways. Moreover, expression data from Drosophila suggests that G6Pase and, hence, gluconeogenesis, initially had a neuronal function. We speculate that in insects-and possibly in some vertebrates-gluconeogenesis may be used as a means of neuronal signaling.

Seasonal variation of macromedusae (Cnidaria at North Bay, Florianópolis, southern Brazil

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Miodeli Nogueira Júnior

2010-06-01

Full Text Available Seasonal variation of large medusae abundance and biomass was studied in the North Bay, Santa Catarina, southern Brazil (27°30'S, 48° 32'W, from February to December 2005. Collecting was conducted seasonally with the help of fishing bottom trawl in 30-minute sections (12 in summer, 18 in each of the remaining seasons in six stations, totaling 66 samples. Eight species were found: the hydrozoans Aequorea sp., Olindias sambaquiensis Müller, 1861, and Rhacostoma atlantica L. Agassiz, 1850; the cubozoans Chiropsalmus quadrumanus (Müller, 1859 and Tamoya haplonema Müller, 1859, and the scyphozoans Aurelia sp., Chrysaora lactea Eschscholtz, 1829 and Lychnorhiza lucerna Haeckel, 1880. Capture rates were low, up to 38 indiv. ha-1, and only ~47% of the samples were positive for jellyfish, comprising 206 individuals. Medusae abundance and species richness clearly changed from one season to another, but did not vary between the sites. Higher species richness (7 out of 8 and greater abundances were recorded during the fall (~60% and 72% of all medusae individuals and biomass respectively. Specific frequency of capture varied from 1.5 to 29% and C. lactea was the only species found in more than 25% of the samples. The three most common species dominated in different periods of the year: C. lactea during fall (78% of individuals and 60% of biomass, R. atlantica during winter (90% of individuals and 17% of biomass, and O. sambaquiensis in spring (78% of individuals and 40% of biomass. Only two individuals were caught during summer, one C. lactea and one R. atlantica. The results offer a general picture of the distribution of the macromedusae in the North Bay, but a continuous monitoring is desirable for a more detailed knowledge on the jellyfish dynamics in the Brazilian coastal waters.

Trends in the diversity, distribution and life history strategy of Arctic Hydrozoa (Cnidaria.

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Marta Ronowicz

Full Text Available This is the first attempt to compile a comprehensive and updated species list for Hydrozoa in the Arctic, encompassing both hydroid and medusa stages and including Siphonophorae. We address the hypothesis that the presence of a pelagic stage (holo- or meroplanktonic was not necessary to successfully recolonize the Arctic by Hydrozoa after the Last Glacial Maximum. Presence-absence data of Hydrozoa in the Arctic were prepared on the basis of historical and present-day literature. The Arctic was divided into ecoregions. Species were grouped into distributional categories according to their worldwide occurrences. Each species was classified according to life history strategy. The similarity of species composition among regions was calculated with the Bray-Curtis index. Average and variation in taxonomic distinctness were used to measure diversity at the taxonomic level. A total of 268 species were recorded. Arctic-boreal species were the most common and dominated each studied region. Nineteen percent of species were restricted to the Arctic. There was a predominance of benthic species over holo- and meroplanktonic species. Arctic, Arctic-Boreal and Boreal species were mostly benthic, while widely distributed species more frequently possessed a pelagic stage. Our results support hypothesis that the presence of a pelagic stage (holo- or meroplanktonic was not necessary to successfully recolonize the Arctic. The predominance of benthic Hydrozoa suggests that the Arctic could have been colonised after the Last Glacial Maximum by hydroids rafting on floating substrata or recolonising from glacial refugia.

Invasive Ponto-Caspian hydrozoan Cordylophora caspia (hydrozoa: Cnidaria) in southern Baltic coastal lakes

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Obolewski, Krystian; Jarosiewicz, Anna; Ożgo, Małgorzata

2015-12-01

Cordylophora caspia Pall. is a highly invasive Ponto-Caspian colonial hydroid with a worldwide distribution. It is a biofouling organism colonizing industrial water installations and causing serious economic problems. Here, we give the first report of its occurrence in southern Baltic coastal lakes, and analyze its distribution in relation to environmental factors and likely colonization routes. Samples were collected from the stalks of Phragmites australis at the total of 102 sites in 15 lakes and lagoons. The species was most numerous in lagoons, i.e. ß-oligohaline water bodies with a surface hydrological connection with the sea, where it reached mean densities of 1200-4800 hydranths m-2. In regression tree analysis, chloride concentration, followed by pH, were the strongest explanatory variables for its occurrence, with highest densities observed at chloride concentration above 1.18 g Cl L-1 and pH 8.05-9.26. At pH 5.77-8.04 higher densities were observed at temperatures above 20.3 °C. Generally, within the range of parameters observed in our study, high densities of C. caspia were associated with high chloride concentration, pH, temperature and electrical conductivity values. The species was also present in freshwater lakes; these colonies may have the highest capacity for future invasions of such habitats. Within lakes, high densities were observed at canals connecting these water bodies with the sea, and at sites close to the inflow of rivers. This distribution pattern can facilitate its further spread into inland waters.

Biodiversity of prokaryotic communities associated with the ectoderm of Ectopleura crocea (Cnidaria, Hydrozoa.

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Cristina Gioia Di Camillo

Full Text Available The surface of many marine organisms is colonized by complex communities of microbes, yet our understanding of the diversity and role of host-associated microbes is still limited. We investigated the association between Ectopleura crocea (a colonial hydroid distributed worldwide in temperate waters and prokaryotic assemblages colonizing the hydranth surface. We used, for the first time on a marine hydroid, a combination of electron and epifluorescence microscopy and 16S rDNA tag pyrosequencing to investigate the associated prokaryotic diversity. Dense assemblages of prokaryotes were associated with the hydrant surface. Two microbial morphotypes were observed: one horseshoe-shaped and one fusiform, worm-like. These prokaryotes were observed on the hydrozoan epidermis, but not in the portions covered by the perisarcal exoskeleton, and their abundance was higher in March while decreased in late spring. Molecular analyses showed that assemblages were dominated by Bacteria rather than Archaea. Bacterial assemblages were highly diversified, with up to 113 genera and 570 Operational Taxonomic Units (OTUs, many of which were rare and contributed to <0.4%. The two most abundant OTUs, likely corresponding to the two morphotypes present on the epidermis, were distantly related to Comamonadaceae (genus Delftia and to Flavobacteriaceae (genus Polaribacter. Epibiontic bacteria were found on E. crocea from different geographic areas but not in other hydroid species in the same areas, suggesting that the host-microbe association is species-specific. This is the first detailed report of bacteria living on the hydrozoan epidermis, and indeed the first study reporting bacteria associated with the epithelium of E. crocea. Our results provide a starting point for future studies aiming at clarifying the role of this peculiar hydrozoan-bacterial association.

Can Aurelia (Cnidaria, Scyphozoa species be differentiated by comparing their scyphistomae and ephyrae?

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Maria Gambill

2014-12-01

Full Text Available Debate exists regarding the number of species of the moon jellyfish (genus Aurelia, a common member of the planktonic community of the coastal shelf seas around the world. Three Aurelia congeners (A. aurita, A. labiata and A. limbata are currently considered to exist but recent genetic analyses suggested that this is an oversimplification. We analyzed the morphological characteristics of scyphistomae, morphological characteristics of ephyrae and differences in the time span of the strobilation process of Aurelia congeners from 17, 7 and 6 different source populations, respectively, of known species. Morphological characteristics of scyphistomae were similar among the 17 populations but those of ephyrae, such as the shape and form of lappets, were effective discriminators in the 6 cases examined. We recommend identifying species based on differences in 1 the morphological characteristics of scyphistomae and ephyrae (and not only medusae, 2 the genetics of individuals, and 3 the geographical occurrence of the population. This study adds to the growing body of knowledge on scyphozoan scyphistomae and ephyrae, stages of the metagenic life cycle of scyphozoans that have received relatively little study compared to medusae.

Competitive interactions among zoanthids (cnidaria: zoanthidae in an intertidal zone of northeastern Brazil

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Emanuelle Fontenele Rabelo

2013-03-01

Full Text Available Sessile organisms that live in consolidated substrates frequently compete for space. Coral species have many strategies to face this competition, including harming their opponents or hindering their growth. In the present study, the competitive interactions between three species of zoanthids were investigated in the intertidal zone of a sandstone reef environment in northeastern Brazil. The competitive abilities of the three species were evaluated by periodic observation of the natural fringes of contact and experimental evaluation of their growth rate through removal of 100 cm² of colonies of each species. Palythoa caribaeorum and Zoanthus sociatus had similar growth rates, and both species grew faster than Protopalythoa variabilis. The recolonization strategy seems to differ among species. The contact fringes between P. caribaeorum and Z. sociatus remained unchanged over time, without any type of aggressive interaction between them, suggesting that stand-off was the strategy used by these organisms. Palythoa caribaeorum and Z. sociatus grew among the polyps of P. variabilis, often killing its colonies. The coexistence of zoanthids reveals a capacity for survival in the face of competition for limited resources such as free substrate, which led to the colonization and establishment of zoanthids in intertidal environments.A competição por espaço é comum em organismos sésseis que vivem em substrato consolidado. Os corais apresentam muitas estratégias para competição por espaço, incluindo danos ao oponente ou inibição do crescimento. No presente estudo, as interações competitivas entre três espécies de zoantídeos foram investigadas em um ambiente de recifes de arenito no nordeste brasileiro. As habilidades competitivas dos zoantídeos foram analisadas por observações periódicas das margens de contato entre as colônias em ambiente natural e avaliação experimental da taxa de crescimento, através da remoção de uma área de 100 cm² de colônias de cada espécie. Palythoa caribaeorum e Zoanthus sociatus apresentaram taxa de crescimento similar, crescendo mais rápido que Protopalythoa variabilis. A estratégia de colonização parece ser diferente entre as espécies. As margens de contato entre P. caribaeorum e Z. sociatus permaneceram inalteradas ao longo do tempo, sem qualquer interação agressiva entre as colônias, sugerindo que a inibição do crescimento foi a estratégia utilizada. Palythoa caribaeorum e Z. sociatus cresceram entre os pólipos de P. variabilis, muitas vezes sufocando e matando suas colônias. A coexistência entre os zoantídeos revela uma capacidade de sobrevivência frente a recursos limitados, como substrato livre, o que levou ao sucesso na colonização e estabelecimento de zoantídeos em ambientes intertidais.

New combinations for two coronate polyp species (Atorellidae and Nausithoidae, Coronatae, Scyphozoa, Cnidaria)

NARCIS (Netherlands)

Morandini, A.C.; Jarms, G.

2005-01-01

Within the order Coronatae, six valid species remain known only by their polyp stage. The inability to relate them to any medusae genera of the group is a problem that remains to be solved in the order. With the examination of type specimens, we reassign the species Stephanoscyphistoma sibogae and

First Description of Sulphur-Oxidizing Bacterial Symbiosis in a Cnidarian (Medusozoa Living in Sulphidic Shallow-Water Environments.

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Sylvie Abouna

Full Text Available Since the discovery of thioautotrophic bacterial symbiosis in the giant tubeworm Riftia pachyptila, there has been great impetus to investigate such partnerships in other invertebrates. In this study, we present the occurrence of a sulphur-oxidizing symbiosis in a metazoan belonging to the phylum Cnidaria in which this event has never been described previously.Scanning Electron Microscope (SEM, Transmission Electron Microscope (TEM observations and Energy-dispersive X-ray spectroscopy (EDXs analysis, were employed to unveil the presence of prokaryotes population bearing elemental sulphur granules, growing on the body surface of the metazoan. Phylogenetic assessments were also undertaken to identify this invertebrate and microorganisms in thiotrophic symbiosis. Our results showed the occurrence of a thiotrophic symbiosis in a cnidarian identified as Cladonema sp.This is the first report describing the occurrence of a sulphur-oxidizing symbiosis in a cnidarian. Furthermore, of the two adult morphologies, the polyp and medusa, this mutualistic association was found restricted to the polyp form of Cladonema sp.

Evolution and development of brain networks: from Caenorhabditis elegans to Homo sapiens.

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Kaiser, Marcus; Varier, Sreedevi

2011-01-01

Neural networks show a progressive increase in complexity during the time course of evolution. From diffuse nerve nets in Cnidaria to modular, hierarchical systems in macaque and humans, there is a gradual shift from simple processes involving a limited amount of tasks and modalities to complex functional and behavioral processing integrating different kinds of information from highly specialized tissue. However, studies in a range of species suggest that fundamental similarities, in spatial and topological features as well as in developmental mechanisms for network formation, are retained across evolution. 'Small-world' topology and highly connected regions (hubs) are prevalent across the evolutionary scale, ensuring efficient processing and resilience to internal (e.g. lesions) and external (e.g. environment) changes. Furthermore, in most species, even the establishment of hubs, long-range connections linking distant components, and a modular organization, relies on similar mechanisms. In conclusion, evolutionary divergence leads to greater complexity while following essential developmental constraints.

Novel scenarios of early animal evolution--is it time to rewrite textbooks?

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Dohrmann, Martin; Wörheide, Gert

2013-09-01

Understanding how important phenotypic, developmental, and genomic features of animals originated and evolved is essential for many fields of biological research, but such understanding depends on robust hypotheses about the phylogenetic interrelationships of the higher taxa to which the studied species belong. Molecular approaches to phylogenetics have proven able to revolutionize our knowledge of organismal evolution. However, with respect to the deepest splits in the metazoan Tree of Life-the relationships between Bilateria and the four non-bilaterian phyla (Porifera, Placozoa, Ctenophora, and Cnidaria)-no consensus has been reached yet, since a number of different, often contradictory, hypotheses with sometimes spectacular implications have been proposed in recent years. Here, we review the recent literature on the topic and contrast it with more classical perceptions based on analyses of morphological characters. We conclude that the time is not yet ripe to rewrite zoological textbooks and advocate a conservative approach when it comes to developing scenarios of the early evolution of animals.

Coral Bleaching Susceptibility Is Decreased following Short-Term (1–3 Year Prior Temperature Exposure and Evolutionary History

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Joshua A. Haslun

2011-01-01

Full Text Available Coral exposed to short periods of temperature stress (≥1.0°C above mean monthly maximum and/or increased frequencies of high temperatures may bolster resilience to global warming associated with climate change. We compared Montastraea cavernosa (Linnaeus, 1767; Cnidaria, Scleractinia, Faviidae from the Florida Keys National Marine Sanctuary (FKNMS and the Flower Garden Banks National Marine Sanctuary (FGBNMS. Thermal stress has been reported frequently within the FKNMS; however, corals in the FGBNMS experience nominal exposures to similar stressors. Corals were exposed to three temperatures (27°C, 31°C, and 35°C for 72 h. Colonies from the FKNMS lost significantly fewer viable and necrotic zooxanthellae under conditions of acute stress (35°C than the FGBNMS colonies. This indicates that the FKNMS corals are less temperature-sensitive than those in the FGBNMS. The observed differences point to greater prior temperature exposure and adaptation in the former versus the latter site when correlated to previous years of thermal exposure.

Cnidarian Neurotoxic Peptides Affecting Central Nervous System Targets.

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Lazcano-Pérez, Fernando; Hernández-Guzmán, Ulises; Sánchez-Rodríguez, Judith; Arreguín-Espinosa, Roberto

2016-01-01

Natural products from animal venoms have been used widely in the discovery of novel molecules with particular biological activities that enable their use as potential drug candidates. The phylum Cnidaria (jellyfish, sea anemones, corals zoanthids, hydrozoans, etc.) is the most ancient venomous phylum on earth. Its venoms are composed of a complex mixture of peptidic compounds with neurotoxic and cytolitic properties that have shown activity on mammalian systems despite the fact that they are naturally targeted against fish and invertebrate preys, mainly crustaceans. For this reason, cnidarian venoms are an interesting and vast source of molecules with a remarkable activity on central nervous system, targeting mainly voltage-gated ion channels, ASIC channels, and TRPV1 receptors. In this brief review, we list the amino acid sequences of most cnidarian neurotoxic peptides reported to date. Additionally, we propose the inclusion of a new type of voltage-gated sea anemone sodium channel toxins based on the most recent reports.

First Description of Sulphur-Oxidizing Bacterial Symbiosis in a Cnidarian (Medusozoa) Living in Sulphidic Shallow-Water Environments.

Science.gov (United States)

Abouna, Sylvie; Gonzalez-Rizzo, Silvina; Grimonprez, Adrien; Gros, Olivier

2015-01-01

Since the discovery of thioautotrophic bacterial symbiosis in the giant tubeworm Riftia pachyptila, there has been great impetus to investigate such partnerships in other invertebrates. In this study, we present the occurrence of a sulphur-oxidizing symbiosis in a metazoan belonging to the phylum Cnidaria in which this event has never been described previously. Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM) observations and Energy-dispersive X-ray spectroscopy (EDXs) analysis, were employed to unveil the presence of prokaryotes population bearing elemental sulphur granules, growing on the body surface of the metazoan. Phylogenetic assessments were also undertaken to identify this invertebrate and microorganisms in thiotrophic symbiosis. Our results showed the occurrence of a thiotrophic symbiosis in a cnidarian identified as Cladonema sp. This is the first report describing the occurrence of a sulphur-oxidizing symbiosis in a cnidarian. Furthermore, of the two adult morphologies, the polyp and medusa, this mutualistic association was found restricted to the polyp form of Cladonema sp.

Antifouling activity by sea anemone (Heteractis magnifica and H. aurora extracts against marine biofilm bacteria Actividades antiincrustantes de las extractos de las anémonas marinas Heteractis magnifica y H. aurora frente a biofilm de bacterias marinas

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Subramanian Bragadeeswaran

2011-07-01

Full Text Available Sea anemones (Actiniaria are solitary, ocean-dwelling members of the phylum Cnidaria and the class Anthozoa. In this study, we screened antibacterial activity of two benthic sea anemones (Heteractis magnifica and H. aurora collected from the Mandapam coast of southeast India. Crude extracts of the sea anemone were assayed against seven bacterial biofilms isolated from three different test panels. The crude extract of H. magnifica showed a maximum inhibition zone of 18 mm against Pseudomonas sp. and Escherichia coli and a minimum inhibition zone of 3 mm against Pseudomonas aeruginosa, Micrococcus sp., and Bacillus cerens for methanol, acetone, and DCM extracts, respectively. The butanol extract of H. aurora showed a maximum inhibition zone of 23 mm against Vibrio parahaemolyticus, whereas the methanol extract revealed a minimum inhibition zone of 1 mm against V. parahaemolyticus. The present study revealed that the H. aurora extracts were more effective than those of H. magnifica and that the active compounds from the sea anemone can be used as antifouling compounds.Las anémonas de mar (Actiniaria son solitarias, habitantes oceánicos del phylum Cnidaria y de la clase Anthozoa. En este estudio se determina la actividad antibacteriana de dos anémonas bentónicas Heteractis magnifica y H. aurora recolectadas en la costa de Mandapam, sudeste de India. Los extractos crudos de estas anémonas fueron ensayados frente a siete biofilms bacterianos aislados de tres paneles de control distintos. El extracto crudo de la anémona H. magnifica mostró una zona inhibición máxima de 18 mm contra Psudomonas sp. y Escherichia coli y la zona de inhibición mínima de 3 mm fue encontrada frente a Pseudomonas aeruginosa, Micrococus sp. y Bacillus cerens de extractos de metanol, acetona y DCM respectivamente. El extracto de butanol de la anémona H. magnifica mostró una zona de inhibición máxima de 23 mm frente a Vibrio parahemolyticus, mientras que con el

The complete mitochondrial genome of Porites harrisoni (Cnidaria: Scleractinia) obtained using next-generation sequencing

KAUST Repository

Terraneo, Tullia Isotta; Arrigoni, Roberto; Benzoni, Francesca; Forsman, Zac H.; Berumen, Michael L.

2018-01-01

In this study, we sequenced the complete mitochondrial genome of Porites harrisoni using ezRAD and Illumina technology. Genome length consisted of 18,630 bp, with a base composition of 25.92% A, 13.28% T, 23.06% G, and 37.73% C. Consistent with other hard corals, P. harrisoni mitogenome was arranged in 13 protein-coding genes, 2 rRNA, and 2 tRNA genes. nad5 and cox1 contained embedded Group I Introns of 11,133 bp and 965 bp, respectively.

Tentacle Transcriptome and Venom Proteome of the Pacific Sea Nettle, Chrysaora fuscescens (Cnidaria: Scyphozoa

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Dalia Ponce

2016-04-01

Full Text Available Jellyfish venoms are rich sources of toxins designed to capture prey or deter predators, but they can also elicit harmful effects in humans. In this study, an integrated transcriptomic and proteomic approach was used to identify putative toxins and their potential role in the venom of the scyphozoan jellyfish Chrysaora fuscescens. A de novo tentacle transcriptome, containing more than 23,000 contigs, was constructed and used in proteomic analysis of C. fuscescens venom to identify potential toxins. From a total of 163 proteins identified in the venom proteome, 27 were classified as putative toxins and grouped into six protein families: proteinases, venom allergens, C-type lectins, pore-forming toxins, glycoside hydrolases and enzyme inhibitors. Other putative toxins identified in the transcriptome, but not the proteome, included additional proteinases as well as lipases and deoxyribonucleases. Sequence analysis also revealed the presence of ShKT domains in two putative venom proteins from the proteome and an additional 15 from the transcriptome, suggesting potential ion channel blockade or modulatory activities. Comparison of these potential toxins to those from other cnidarians provided insight into their possible roles in C. fuscescens venom and an overview of the diversity of potential toxin families in cnidarian venoms.

LOS HIDROZOOS (CNIDARIA, HYDROZOA DE LA CAYERÍA SUR DEL GOLFO DE BATABANÓ, CUBA

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Susel Castellanos Iglesias

2011-12-01

Full Text Available Hidrozoos de aguas poco profundas fueron recolectados en 17 estaciones, en julio del 2004. Las estaciones se localizaron en manglares, pastos marinos y arrecifes coralinos. Se encontraron hidrozoos de dos subclases (Anthoathecata y Leptothecata, 11 familias, 27 géneros y 34 especies. Se indican la localidad de recolecta, la profundidad, el tipo de sustrato, la descripción y las figuras de 15 especies de hidrozoos  tecados. Se confirma la presencia de Hebellopsis communis Calder, 1991a y Antennella siliquosa (Hincks, 1877 para el Mar Caribe. Se expresa la abundancia relativa en tres categorías: abundante, común y rara. Las especies más abundantes fueron Dynamena crisioides Lamouroux, 1824 en el hábitat de manglar, Cnydoscyphus marginatus (Allman, 1877 y Sertularella diaphana (Allman, 1885 en los arrecifes. Monostaechas quadridens (McCrady, 1859 y Diphasia tropica Nutting, 1904 fueron de baja representación en las muestras. Los sustratos más colonizados fueron la raíz sumergida de mangle rojo y las esponjas en arrecife. El hidrozoo más colonizado fue C. marginatus. El material fue depositado en la colección de invertebrados marinos del Acuario Nacional de Cuba. ABSTRACT Hydrozoans from shallow waters were collected at 17 stations in July 2004. Stations were located in mangrove forests, seagrass meadows and coral reefs. Two subclases (Anthoathecata and Leptothecata of hydrozoans were found, including 11 families, 27 genera and 34 species. The collection site, depth, type of substrate, description and pictures are recorded for the fifteenth thecate hydrozoan species. The presence of Hebellopsis communis Calder, 1991a and Antennella siliquos (Hincks, 1877 is confirmed for the Caribbean Sea. The relative abundance is expressed in three categories: abundant, common and rare. Most abundant species were Dynamena crisioides Lamouroux, 1824 in mangrove habitat, Cnydoscyphus marginatus (Allman, 1877 and Sertularella diaphana (Allman, 1885 in coral reefs. Monostaechas quadridens (McCrady, 1859 and Diphasia tropica Nutting, 1904 were rare in general. The most colonized substrates were the submerged red mangrove roots and sponges in the reef. The most colonized hydrozoan was C. marginatus. Specimens were deposited in the collection of marine invertebrates at the National Aquarium of Cuba.

Using ezRAD to reconstruct the complete mitochondrial genome of Porites fontanesii (Cnidaria: Scleractinia)

KAUST Repository

Terraneo, Tullia Isotta; Arrigoni, Roberto; Benzoni, Francesca; Forsman, Zac H.; Berumen, Michael L.

2018-01-01

Corals in the genus Porites are among the major framework builders of reef structures worldwide, yet the genus has been challenging to study due to a lack of informative molecular markers. Here, we used ezRAD sequencing to reconstruct the complete mitochondrial genome of Porites fontanesii (GenBank accession number MG754069), a widespread coral species endemic to the Red Sea and Gulf of Aden. The gene arrangement of P. fontanesii did not differ from other Scleractinia and consisted of 18,658 bp, organized in 13 protein-coding genes, 2 rRNA genes, and 2 tRNA genes. This mitochondrial genome contributes essential data to work towards a better understanding of evolutionary relationships within Porites.

Combining bathymetry, latitude, and phylogeny to understand the distribution of deep Atlantic hydroids (Cnidaria)

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Fernandez, Marina O.; Marques, Antonio C.

2018-03-01

Water depth is associated with significant environmental changes and gradients that, together with biotic, geological, and evolutionary processes, define bathymetric ranges of individuals, populations, species, and even communities. However, inferences on bathymetric ranges of marine invertebrates are usually based on a few taxa or on restricted regional scales. In this study, we present a comprehensive literature survey of hydroids for the Atlantic Ocean and adjacent Arctic and Antarctic seas for records deeper than 50 m. We used these records in bathymetrical analyses along latitude and compared major patterns under an evolutionary framework. Our results show that hydroids are frequent inhabitants of the deep sea with mainly eurybathic species that extend their distributions from shallower to deeper waters, being rarely exclusively bathyal or abyssal. We also found increasing bathymetric ranges with mean depths of occurrence of the species for both families and regions. Moreover, vertical distribution proved to be taxonomically and regionally dependent, with reduced eurybathy in "Antarctic" species but increased eurybathy in "Tropical" and "Subtropical North" regions. Data also support early colonization of the deep sea in the evolution of the group. Finally, the unequal number of records across latitudes, scant at Equatorial and southern Tropical latitudes, provides evidence to the historically uneven sampling effort in the different regions of the Atlantic.

Using ezRAD to reconstruct the complete mitochondrial genome of Porites fontanesii (Cnidaria: Scleractinia)

KAUST Repository

Terraneo, Tullia Isotta

2018-02-09

Corals in the genus Porites are among the major framework builders of reef structures worldwide, yet the genus has been challenging to study due to a lack of informative molecular markers. Here, we used ezRAD sequencing to reconstruct the complete mitochondrial genome of Porites fontanesii (GenBank accession number MG754069), a widespread coral species endemic to the Red Sea and Gulf of Aden. The gene arrangement of P. fontanesii did not differ from other Scleractinia and consisted of 18,658 bp, organized in 13 protein-coding genes, 2 rRNA genes, and 2 tRNA genes. This mitochondrial genome contributes essential data to work towards a better understanding of evolutionary relationships within Porites.

Bargmannia lata, an undescribed species of physonect siphonophore (Cnidaria: Hydrozoa) from Canadian Pacific waters

NARCIS (Netherlands)

Mapstone, G.M.

1998-01-01

A new species of Bargmannia Totton, 1954, Bargmannia lata, is described from samples collected from Vancouver Island, BC, Canada. Differences from type material of Bargmannia elongata Totton, 1954, are noted.

Tentacle Transcriptome and Venom Proteome of the Pacific Sea Nettle, Chrysaora fuscescens (Cnidaria: Scyphozoa)

Science.gov (United States)

Ponce, Dalia; Brinkman, Diane L.; Potriquet, Jeremy; Mulvenna, Jason

2016-01-01

Jellyfish venoms are rich sources of toxins designed to capture prey or deter predators, but they can also elicit harmful effects in humans. In this study, an integrated transcriptomic and proteomic approach was used to identify putative toxins and their potential role in the venom of the scyphozoan jellyfish Chrysaora fuscescens. A de novo tentacle transcriptome, containing more than 23,000 contigs, was constructed and used in proteomic analysis of C. fuscescens venom to identify potential toxins. From a total of 163 proteins identified in the venom proteome, 27 were classified as putative toxins and grouped into six protein families: proteinases, venom allergens, C-type lectins, pore-forming toxins, glycoside hydrolases and enzyme inhibitors. Other putative toxins identified in the transcriptome, but not the proteome, included additional proteinases as well as lipases and deoxyribonucleases. Sequence analysis also revealed the presence of ShKT domains in two putative venom proteins from the proteome and an additional 15 from the transcriptome, suggesting potential ion channel blockade or modulatory activities. Comparison of these potential toxins to those from other cnidarians provided insight into their possible roles in C. fuscescens venom and an overview of the diversity of potential toxin families in cnidarian venoms. PMID:27058558

The complete mitochondrial genome of Porites harrisoni (Cnidaria: Scleractinia) obtained using next-generation sequencing

KAUST Repository

Terraneo, Tullia Isotta

2018-02-24

In this study, we sequenced the complete mitochondrial genome of Porites harrisoni using ezRAD and Illumina technology. Genome length consisted of 18,630 bp, with a base composition of 25.92% A, 13.28% T, 23.06% G, and 37.73% C. Consistent with other hard corals, P. harrisoni mitogenome was arranged in 13 protein-coding genes, 2 rRNA, and 2 tRNA genes. nad5 and cox1 contained embedded Group I Introns of 11,133 bp and 965 bp, respectively.

Growth of the tropical zoanthid Palythoa caribaeorum (Cnidaria: Anthozoa on reefs in northeastern Brazil

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JANINE F. SILVA

2015-06-01

Full Text Available In Brazilian reefs, zoanthids, especially Palythoa caribaeorum are fundamental for structuring the local benthic community. The objective of this study was to determine the growth rate of P. caribaeorum, and to assess the influence of the site (different beaches, season (dry and wet, location (intertidal or infralittoral zones, and human pressure associated with tourism. For one year we monitored the cover of P. caribaeorum in transects and focused on 20 colonies. We cut off a square (100 cm2 from the central part of the colony and monitored the bare area for four months in each season. The average growth rates varied from 0.015 and 0.021 cm.day-1. The rate was homogeneous in all localities, and there was no influence from colony site, location, or touristic visitation, showing that the growth velocity may be an intrinsic characteristic of the species, with a strong genetic component. The growth rate of P. caribaeorum differed among months, and peaked in the first month after injury. The average cover varied from 6.2 to 22.9% and was lower on the reef visited by tourists. The present study corroborates the hypothesis that P. caribaeorum is important for coastal reef dynamics due to its fast and continuous growth.

Growth of the tropical zoanthid Palythoa caribaeorum (Cnidaria: Anthozoa) on reefs in northeastern Brazil.

Science.gov (United States)

Silva, Janine F; Gomes, Paula B; Santana, Erika C; Silva, João M; Lima, Érica P; Santos, Andre M M; Pérez, Carlos D

2015-01-01

In Brazilian reefs, zoanthids, especially Palythoa caribaeorum are fundamental for structuring the local benthic community. The objective of this study was to determine the growth rate of P. caribaeorum, and to assess the influence of the site (different beaches), season (dry and wet), location (intertidal or infralittoral zones), and human pressure associated with tourism. For one year we monitored the cover of P. caribaeorum in transects and focused on 20 colonies. We cut off a square (100 cm2) from the central part of the colony and monitored the bare area for four months in each season. The average growth rates varied from 0.015 and 0.021 cm.day(-1). The rate was homogeneous in all localities, and there was no influence from colony site, location, or touristic visitation, showing that the growth velocity may be an intrinsic characteristic of the species, with a strong genetic component. The growth rate of P. caribaeorum differed among months, and peaked in the first month after injury. The average cover varied from 6.2 to 22.9% and was lower on the reef visited by tourists. The present study corroborates the hypothesis that P. caribaeorum is important for coastal reef dynamics due to its fast and continuous growth.

Hidden diversity and evolutionary trends in malacosporean parasites (Cnidaria: Myxozoa) identified using molecular phylogenetics

Czech Academy of Sciences Publication Activity Database

Bartošová, Pavla; Hrabcová, M.; Pecková, Hana; Patra, Sneha; Kodádková, Alena; Jurajda, Pavel; Tyml, Tomáš; Holzer, Astrid S.

2014-01-01

Roč. 44, č. 8 (2014), s. 565-577 ISSN 0020-7519 R&D Projects: GA ČR(CZ) GPP506/11/P724; GA ČR GBP505/12/G112; GA AV ČR(CZ) M200961205 Institutional support: RVO:60077344 ; RVO:68081766 Keywords : Buddenbrockia * Tetracapsuloides * diversity * phylogeny * Bryozoa * fish * cryptic * worm Subject RIV: EB - Genetics ; Molecular Biology; EG - Zoology (UBO-W) Impact factor: 3.872, year: 2014

Reproductive biology of Palythoa caribaeorum and Protopalythoa variabilis (Cnidaria, Anthozoa, Zoanthidea from the southeastern coast of Brazil Biologia reprodutiva de Palythoa caribaeorum e Protopalythoa variabilis (Cnidaria: Anthozoa: Zoanthidea da costa sudeste do Brasil

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H. K. Boscolo

2005-02-01

Full Text Available The reproductive biology of Palythoa caribaeorum (Duchassaing & Michelotti 1860 and Protopalythoa variabilis (Duerden 1898 was studied through monthly samples from tagged colonies from June 1996 to June 1997, in São Sebastião channel, São Paulo, Brazil (45º26'W, 23º50'S. The gametogenesis was similar to that of other zoanthids as shown by histological preparations. Oocyte diameters and maturation stages of testis vesicles were evaluated on squash preparations. Both species showed sequential protogynic hermaphroditism, with high frequency of fertile polyps (83% in P. variabilis and 72% in P. caribaeorum, high frequency of colonies in female sex condition (65.3% of P. variabilis and 41.7% of P. caribaeorum, and apparently continuous gametogenesis. In P. caribaeorum, egg release was continuous and sperm release took place during half of the analyzed period. In P. variabilis, egg and sperm release occurred in April-May and February-March 1997, respectively.A biologia reprodutiva de Palythoa caribaeorum (Duchassaing & Michelotti 1860 e Protopalythoa variabilis (Duerden 1898 foi estudada por amostras mensais de colônias etiquetadas de junho de 1996 a junho de 1997, no canal de São Sebastião, São Paulo, Brasil (45º26'W, 23º50'S. A gametogênese apresentou-se semelhante à de outros zoantídeos, como evidenciado em preparações histológicas. O diâmetro dos oócitos e os estágios de maturação dos folículos testiculares foram avaliados por preparações do tipo "squash". Ambas as espécies mostraram hermafroditismo seqüencial protogínico, com alta freqüência de pólipos férteis (83% em P. variabilis e 72% em P. caribaeorum e de colônias na condição sexual feminina (65,3% para P. variabilis e 41,7% para P. caribaeorum, e, aparentemente, gametogênese contínua. Em P. caribaeorum, a liberação de oócitos foi contínua e a liberação de espermatozóides ocorreu durante metade do período analisado. Para P. variabilis, a liberação de oócitos e de espermatozóides ocorreu em abril-maio e fevereiro-março de 1997, respectivamente.

Fouling assemblage of benthic plastic debris collected from Mersin Bay, NE Levantine coast of Turkey.

Science.gov (United States)

Gündoğdu, Sedat; Çevik, Cem; Karaca, Serkan

2017-11-15

The Mediterranean is an ecosystem that faces more and more microplastic pollution every day. This causes the whole of the Mediterranean to face the negative effects of plastic pollution. This study examines the state of plastic debris and fouling organisms found on it in one of the areas most affected by plastic pollution, Mersin Bay. As a result, a total of 3.88kg plastic (mean=0,97kg; n=120; 2670item/km 2 ; 86,3kg/km 2 ) was collected and based on the ATR-FTIR analysis, it was determined that this total contained 9 types of plastics. 17 different fouling species belonging to 6 phylum (Annelida, Arthropoda, Bryozoa, Chordata, Cnidaria, Mollusca) 7 class and 11 order were discovered on plastics. Spirobranchus triqueter, Hydroides sp. and Neopycnodonte cochlear were the most abundant species. In the end, the example of Mersin Bay shows that plastic debris as a substrate can contain a very high diversity of life just like natural substrates. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Sponge Zygomycale parishii(Bowerbank) and its Endobiotic Fauna

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Duarte, Luiz; Nalesso, Rosebel

1996-02-01

The endobiotic fauna of the sponge Zygomycale parishii(Bowerbank) was studied for 2·5 years at two sites, Ubatuba and São Sebastião, on the northern coast of the State of São Paulo, Brazil. Ninety-two macrofaunal species (over 1 mm long) were identified among which Cnidaria, Turbellaria, Nemertinea, Sipuncula, Polychaeta, Mollusca, Crustacea, Pycnogonida, Echinodermata, Ascidiacea and Pisces were represented. The results obtained on the number of species (species richness), the abundances of different species and faunal composition were related to the physico-biotic characteristics of the study sites. The influence of sample volume and other methodological artifacts on sample characteristics were also examined. The ophiuroid Ophiactis savignyi(Müller & Troschell) was the dominant endobiotic species, comprising 64% of all individuals collected. The São Sebastião endobiotic fauna was more diversified than the Ubatuba endobiotic fauna, possibly due to higher larval recruitment, and to the closeness of Z. parishiito the sea-floor providing a greater possibility for inhabitants of this microhabitat to find and to live inside the sponge.

Characterization of Translationally Controlled Tumour Protein from the Sea Anemone Anemonia viridis and Transcriptome Wide Identification of Cnidarian Homologues.

Science.gov (United States)

Nicosia, Aldo; Bennici, Carmelo; Biondo, Girolama; Costa, Salvatore; Di Natale, Marilena; Masullo, Tiziana; Monastero, Calogera; Ragusa, Maria Antonietta; Tagliavia, Marcello; Cuttitta, Angela

2018-01-11

Gene family encoding translationally controlled tumour protein (TCTP) is defined as highly conserved among organisms; however, there is limited knowledge of non-bilateria. In this study, the first TCTP homologue from anthozoan was characterised in the Mediterranean Sea anemone, Anemonia viridis . The release of the genome sequence of Acropora digitifera , Exaiptasia pallida , Nematostella vectensis and Hydra vulgaris enabled a comprehensive study of the molecular evolution of TCTP family among cnidarians. A comparison among TCTP members from Cnidaria and Bilateria showed conserved intron exon organization, evolutionary conserved TCTP signatures and 3D protein structure. The pattern of mRNA expression profile was also defined in A. viridis . These analyses revealed a constitutive mRNA expression especially in tissues with active proliferation. Additionally, the transcriptional profile of A. viridis TCTP ( AvTCTP ) after challenges with different abiotic/biotic stresses showed induction by extreme temperatures, heavy metals exposure and immune stimulation. These results suggest the involvement of AvTCTP in the sea anemone defensome taking part in environmental stress and immune responses.

Characterization of Translationally Controlled Tumour Protein from the Sea Anemone Anemonia viridis and Transcriptome Wide Identification of Cnidarian Homologues

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Aldo Nicosia

2018-01-01

Full Text Available Gene family encoding translationally controlled tumour protein (TCTP is defined as highly conserved among organisms; however, there is limited knowledge of non-bilateria. In this study, the first TCTP homologue from anthozoan was characterised in the Mediterranean Sea anemone, Anemonia viridis. The release of the genome sequence of Acropora digitifera, Exaiptasia pallida, Nematostella vectensis and Hydra vulgaris enabled a comprehensive study of the molecular evolution of TCTP family among cnidarians. A comparison among TCTP members from Cnidaria and Bilateria showed conserved intron exon organization, evolutionary conserved TCTP signatures and 3D protein structure. The pattern of mRNA expression profile was also defined in A. viridis. These analyses revealed a constitutive mRNA expression especially in tissues with active proliferation. Additionally, the transcriptional profile of A. viridis TCTP (AvTCTP after challenges with different abiotic/biotic stresses showed induction by extreme temperatures, heavy metals exposure and immune stimulation. These results suggest the involvement of AvTCTP in the sea anemone defensome taking part in environmental stress and immune responses.

Evo-devo of non-bilaterian animals

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Emilio Lanna

2015-09-01

Full Text Available The non-bilaterian animals comprise organisms in the phyla Porifera, Cnidaria, Ctenophora and Placozoa. These early-diverging phyla are pivotal to understanding the evolution of bilaterian animals. After the exponential increase in research in evolutionary development (evo-devo in the last two decades, these organisms are again in the spotlight of evolutionary biology. In this work, I briefly review some aspects of the developmental biology of nonbilaterians that contribute to understanding the evolution of development and of the metazoans. The evolution of the developmental genetic toolkit, embryonic polarization, the origin of gastrulation and mesodermal cells, and the origin of neural cells are discussed. The possibility that germline and stem cell lineages have the same origin is also examined. Although a considerable number of non-bilaterian species are already being investigated, the use of species belonging to different branches of non-bilaterian lineages and functional experimentation with gene manipulation in the majority of the non-bilaterian lineages will be necessary for further progress in this field.

Medicinal benefits of marine invertebrates: sources for discovering natural drug candidates.

Science.gov (United States)

De Zoysa, Mahanama

2012-01-01

Marine invertebrates are one of the major groups of organisms, which could be diversified under the major taxonomic groups of Porifera, Cnidaria, Mollusca, Arthropoda, Echinodermata, and many other minor phyla. To date, range of medicinal benefits and a significant number of marine natural products (MNPs) have been discovered from marine invertebrates. Seafood diet from edible marine invertebrates such as mollusks and crustaceans has been linked with various medicinal benefits to improve human health. Among marine invertebrates, spongers from phylum Porifera is the most dominant group responsible for discovering large number of MNPs, which have been used as template to develop therapeutic drugs. MNPs isolated from invertebrates have shown wide range of therapeutic properties including antimicrobial, antioxidant, antihypertensive, anticoagulant, anticancer, anti-inflammatory, wound healing and immune modulator, and other medicinal effects. Therefore, marine invertebrates are rich sources of chemical diversity and health benefits for developing drug candidates, cosmetics, nutritional supplements, and molecular probes that can be supported to increase the healthy life span of human. Copyright © 2012 Elsevier Inc. All rights reserved.

Spatial distribution and abundance of nonindigenous coral genus Tubastraea (Cnidaria, Scleractinia around Ilha Grande, Brazil

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A. F. Paula

Full Text Available The distribution and abundance of azooxanthellate coral Tubastraea Lesson, 1829 were examined at different depths and their slope preference was measured on rocky shores on Ilha Grande, Brazil. Tubastraea is an ahermatypic scleractinian nonindigenous to Brazil, which probably arrived on a ship's hull or oil platform in the late 1980's. The exotic coral was found along a great geographic range of the Canal Central of Ilha Grande, extending over a distance of 25 km. The abundance of Tubastraea was quantified by depth, using three different sampling methods: colony density, visual estimation and intercept points (100 for percentage of cover. Tubastraea showed ample tolerance to temperature and desiccation since it was found more abundantly in very shallow waters (0.1-0.5 m, despite the fact that hard substratum is available at greater depths at all the stations sampled. At most sites, 1 to 5 colonies per 0.25 m² were found most frequently, but occasionally more than 50 colonies were found per 0.25 m², indicating a somewhat gregarious spatial distribution for this coral. The coral Tubastraea was found to occupy slopes of every possible angle in the Canal Central of Ilha Grande, but more colonies were found occupying slopes of 80 to 100°. Therefore, its insensitivity to angles of recruitment and its tolerance for different depths makes it an organism with great ecological tolerance, with a potential to colonize new areas and increase its current range in Brazil's coastal waters.

Barcoding Techniques Help Tracking the Evolutionary History of the Introduced Species Pennaria disticha (Hydrozoa, Cnidaria.

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Maria Pia Miglietta

Full Text Available The Christmas tree hydroid Pennaria disticha is listed as one of the most common introduced species in Hawaii. Firstly reported in Kaneohe Bay (Oahu in 1928, it is now established throughout the entire archipelago, including the Northwestern Hawaiian Islands, a U.S. National Monument and World Heritage site. The Hawaiian population of P. disticha has also been reported as being the source of further introductions to Palmyra Atoll in the U.S. Line Islands. Using a phylogenetic hypothesis based on a 611 base pair fragment of the mitochondrial 16S barcoding gene, we demonstrate that P. disticha is a complex of cryptic species, rather than one species with cosmopolitan distribution. We also show that in Hawaii there are three species of Pennaria, rather than one introduced species. Two of these species share haplotypes with specimens from distant locations such as Florida and Panama and may have been introduced, possibly from the Atlantic Ocean. A third species could either represent a lineage with nearly cosmopolitan distribution, or another introduced species. Our dataset refutes the widely accepted idea that only one lineage of P. disticha is present in Hawaii. On the contrary, P. disticha in Hawaii may be the outcome of multiple independent introductions of several morphologically undistinguishable cryptic lineages. Our results uncover an unsuspected complexity within the very common hydroid P. disticha, and highlight the need for routine use of molecular tools, such as DNA barcoding, to improve the identification and recognition of non-indigenous species.

Evolution of life cycle, colony morphology, and host specificity in the family Hydractiniidae (Hydrozoa, Cnidaria).

Science.gov (United States)

Miglietta, Maria Pia; Cunningham, Clifford W

2012-12-01

Biased transitions are common throughout the tree of life. The class hydrozoa is no exception, having lost the feeding medusa stage at least 70 times. The family hydractiniidae includes one lineage with pelagic medusae (Podocoryna) and several without (e.g., Hydractinia). The benthic colony stage also varies widely in host specificity and in colony form. The five-gene phylogeny presented here requires multiple transitions between character states for medusae, host specificity, and colony phenotype. Significant phylogenetic correlations exist between medusoid form, colony morphology, and host specificity. Species with nonfeeding medusae are usually specialized on a single host type, and reticulate colonies are correlated with nonmotile hosts. The history of feeding medusae is less certain. Podocoryna is nested within five lineages lacking medusae. This requires either repeated losses of medusae, or the remarkable re-evolution of a feeding medusa after at least 150 million years. Traditional ancestral reconstruction favors medusa regain, but a likelihood framework testing biased transitions cannot distinguish between multiple losses versus regain. A hypothesis of multiple losses of feeding medusae requires transient selection pressure favoring such a loss. Populations of species with feeding medusae are always locally rare and lack of feeding medusae does not result in restricted species distribution around the world. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

Functional studies on the role of Notch signaling in Hydractinia development.

Science.gov (United States)

Gahan, James M; Schnitzler, Christine E; DuBuc, Timothy Q; Doonan, Liam B; Kanska, Justyna; Gornik, Sebastian G; Barreira, Sofia; Thompson, Kerry; Schiffer, Philipp; Baxevanis, Andreas D; Frank, Uri

2017-08-01

The function of Notch signaling was previously studied in two cnidarians, Hydra and Nematostella, representing the lineages Hydrozoa and Anthozoa, respectively. Using pharmacological inhibition in Hydra and a combination of pharmacological and genetic approaches in Nematostella, it was shown in both animals that Notch is required for tentacle morphogenesis and for late stages of stinging cell maturation. Surprisingly, a role for Notch in neural development, which is well documented in bilaterians, was evident in embryonic Nematostella but not in adult Hydra. Adult neurogenesis in the latter seemed to be unaffected by DAPT, a drug that inhibits Notch signaling. To address this apparent discrepancy, we studied the role of Notch in Hydractinia echinata, an additional hydrozoan, in all life stages. Using CRISPR-Cas9 mediated mutagenesis, transgenesis, and pharmacological interference we show that Notch is dispensable for Hydractinia normal neurogenesis in all life stages but is required for the maturation of stinging cells and for tentacle morphogenesis. Our results are consistent with a conserved role for Notch in morphogenesis and nematogenesis across Cnidaria, and a lineage-specific loss of Notch dependence in neurogenesis in hydrozoans. Copyright © 2017 Elsevier Inc. All rights reserved.

Antimicrobial peptides in marine invertebrate health and disease.

Science.gov (United States)

Destoumieux-Garzón, Delphine; Rosa, Rafael Diego; Schmitt, Paulina; Barreto, Cairé; Vidal-Dupiol, Jeremie; Mitta, Guillaume; Gueguen, Yannick; Bachère, Evelyne

2016-05-26

Aquaculture contributes more than one-third of the animal protein from marine sources worldwide. A significant proportion of aquaculture products are derived from marine protostomes that are commonly referred to as 'marine invertebrates'. Among them, penaeid shrimp (Ecdysozosoa, Arthropoda) and bivalve molluscs (Lophotrochozoa, Mollusca) are economically important. Mass rearing of arthropods and molluscs causes problems with pathogens in aquatic ecosystems that are exploited by humans. Remarkably, species of corals (Cnidaria) living in non-exploited ecosystems also suffer from devastating infectious diseases that display intriguing similarities with those affecting farmed animals. Infectious diseases affecting wild and farmed animals that are present in marine environments are predicted to increase in the future. This paper summarizes the role of the main pathogens and their interaction with host immunity, with a specific focus on antimicrobial peptides (AMPs) and pathogen resistance against AMPs. We provide a detailed review of penaeid shrimp AMPs and their role at the interface between the host and its resident/pathogenic microbiota. We also briefly describe the relevance of marine invertebrate AMPs in an applied context.This article is part of the themed issue 'Evolutionary ecology of arthropod antimicrobial peptides'. © 2016 The Author(s).

Radioactive contamination of Bunodosoma caissarum under controlled conditions

International Nuclear Information System (INIS)

Santos Gouvea, R. de C. dos; Santos, P.L. dos

The kinetics of uptake and release of radionuclides 137 Cs, 131 I, 133 Ba, 51 Cr (III and VI), 60 Co and 65 Zn in the 'cnidaria' Bunodosoma caissarum have been studied. This is an exclusively Brazilian species and easily collected on the Rio de Janeiro coastal waters. The kinetic experiments have been made in aquariums of 1000 cm 3 , in laboratory under controlled conditions and accompanied by single channel radiometry. The velocities of concentration were evident to radionuclides 131 I and 133 Ba. The larger concentration factors were registred to 51 Cr (III), 65 Zn and 51 Cr (VI), with middle values of 20,0 , 14,5 and 8,6 respectively. The same radionuclides stood out in the loss experiments, presenting the following biological half-lives : 292,2 h ( 51 Cr-III), 784,0 h ( 51 Cr-VI) and 823,0 h ( 65 Zn). This expressive value for the 65 Zn suggests a probable biological integration of this radionuclide by the species studied. The results allow us to indicate the 'anthozoa' Bunodosoma caissarum as a bioindicator of the radioactive contamination of the marine environment. (Author) [pt

Establishment of primary cell culture from the temperate symbiotic cnidarian, Anemonia viridis.

Science.gov (United States)

Barnay-Verdier, Stéphanie; Dall'osso, Diane; Joli, Nathalie; Olivré, Juliette; Priouzeau, Fabrice; Zamoum, Thamilla; Merle, Pierre-Laurent; Furla, Paola

2013-10-01

The temperate symbiotic sea anemone Anemonia viridis, a member of the Cnidaria phylum, is a relevant experimental model to investigate the molecular and cellular events involved in the preservation or in the rupture of the symbiosis between the animal cells and their symbiotic microalgae, commonly named zooxanthellae. In order to increase research tools for this model, we developed a primary culture from A. viridis animal cells. By adapting enzymatic dissociation protocols, we isolated animal host cells from a whole tentacle in regeneration state. Each plating resulted in a heterogeneous primary culture consisted of free zooxanthellae and many regular, small rounded and adherent cells (of 3-5 μm diameter). Molecular analyses conducted on primary cultures, maintained for 2 weeks, confirmed a specific signature of A. viridis cells. Further serial dilutions and micromanipulation allowed us to obtain homogenous primary cultures of the small rounded cells, corresponding to A. viridis "epithelial-like cells". The maintenance and the propagation over a 4 weeks period of primary cells provide, for in vitro cnidarian studies, a preliminary step for further investigations on cnidarian cellular pathways notably in regard to symbiosis interactions.

The TALE face of Hox proteins in animal evolution.

Science.gov (United States)

Merabet, Samir; Galliot, Brigitte

2015-01-01

Hox genes are major regulators of embryonic development. One of their most conserved functions is to coordinate the formation of specific body structures along the anterior-posterior (AP) axis in Bilateria. This architectural role was at the basis of several morphological innovations across bilaterian evolution. In this review, we traced the origin of the Hox patterning system by considering the partnership with PBC and Meis proteins. PBC and Meis belong to the TALE-class of homeodomain-containing transcription factors and act as generic cofactors of Hox proteins for AP axis patterning in Bilateria. Recent data indicate that Hox proteins acquired the ability to interact with their TALE partners in the last common ancestor of Bilateria and Cnidaria. These interactions relied initially on a short peptide motif called hexapeptide (HX), which is present in Hox and non-Hox protein families. Remarkably, Hox proteins can also recruit the TALE cofactors by using specific PBC Interaction Motifs (SPIMs). We describe how a functional Hox/TALE patterning system emerged in eumetazoans through the acquisition of SPIMs. We anticipate that interaction flexibility could be found in other patterning systems, being at the heart of the astonishing morphological diversity observed in the animal kingdom.

First records of Parazoanthidae and Microzoanthidae (Anthozoa: Hexacorallia: Zoantharia) from the Red Sea

KAUST Repository

Reimer, James Davis

2014-01-01

Here we report on the first records of the families Parazoanthidae and Microzoanthidae and by extension for the suborder Macrocnemina (Cnidaria: Anthozoa: Hexacorallia: Zoantharia) from the Red Sea. Despite a long history of zoantharian research in the region, previous records only reported species of the suborder Brachycnemina, from the genera Zoanthus and Palythoa. Both Parazoanthus sp. and Microzoanthus sp. specimens were first found from the same small coral cave at a reef at Jaz\\'air Sila, Saudi Arabia, and subsequently observed at another location in the northern Red Sea. Numerous Antipathozoanthus sp. colonies were observed at Marker 9 north of Yanbu, Saudi Arabia in association with antipatharians inside small caves. The Parazoanthus sp. was in association with numerous encrusting sponge species on the roof of the cave, similar to previously reported undescribed species in the Pacific Ocean. Microzoanthus sp. was found on hard rubble on the cave floor. These records represent large range extensions (e.g. thousands of kilometres) for each genus, demonstrating the overall lack of research on the order Zoantharia, especially within the Red Sea. © Marine Biological Association of the United Kingdom, 2014.

First records of Parazoanthidae and Microzoanthidae (Anthozoa: Hexacorallia: Zoantharia) from the Red Sea

KAUST Repository

Reimer, James Davis; Uyeno, Daisuke; Berumen, Michael L.

2014-01-01

Here we report on the first records of the families Parazoanthidae and Microzoanthidae and by extension for the suborder Macrocnemina (Cnidaria: Anthozoa: Hexacorallia: Zoantharia) from the Red Sea. Despite a long history of zoantharian research in the region, previous records only reported species of the suborder Brachycnemina, from the genera Zoanthus and Palythoa. Both Parazoanthus sp. and Microzoanthus sp. specimens were first found from the same small coral cave at a reef at Jaz'air Sila, Saudi Arabia, and subsequently observed at another location in the northern Red Sea. Numerous Antipathozoanthus sp. colonies were observed at Marker 9 north of Yanbu, Saudi Arabia in association with antipatharians inside small caves. The Parazoanthus sp. was in association with numerous encrusting sponge species on the roof of the cave, similar to previously reported undescribed species in the Pacific Ocean. Microzoanthus sp. was found on hard rubble on the cave floor. These records represent large range extensions (e.g. thousands of kilometres) for each genus, demonstrating the overall lack of research on the order Zoantharia, especially within the Red Sea. © Marine Biological Association of the United Kingdom, 2014.

Gigantic oocytes in the deep sea black coral Dendrobathypathes grandis (Antipatharia) from the Mar del Plata submarine canyon area (southwestern Atlantic)

Science.gov (United States)

Lauretta, Daniel; Penchaszadeh, Pablo E.

2017-10-01

The black coral Dendrobathypathes grandis (Cnidaria: Antipatharia) is studied for the first time in the southwestern Atlantic off Argentina. This is the only antipatharian reported from the Atlantic between 35°S and 54°S. Eleven specimens were collected at depths of 819-2204 m during three expeditions to the Mar del Plata submarine canyon (2012-2013); seven were females. The species is gonochoric, and the polyps in female colonies contain up to nine oocytes per polyp, which can reach 1500 μm in diameter. In contrast, the largest oocyte currently reported for antipatharians is 500 μm, and usual diameters do not exceed 200 μm. These large oocytes have over 20 times more volume than the biggest oocyte reported, but over 800 times more volume when compared with the common oocyte size of the group. Sperm size and morphology is similar to previous data from other species. As in previous studies, neither embryos nor larvae were found in any specimens. This species was previously only reported from waters off South Georgia Island, and so these specimens expand the known distribution north by 1800 km.

Jellyfish stinging is driven by the moving front of the nematocyst's tubule

Science.gov (United States)

Shavit, Uri; Park, Sinwook; Piriatinskiy, Gadi; Yossifon, Gilad; Lotan, Tamar

2017-11-01

Nematocysts are ultra-fast stinging organelles that are utilized by the Cnidaria phylum for prey capture, defense and locomotion. They consist of a capsule and a tubule and exert high pressure and acceleration to penetrate the target organism. Previous studies report that the ejection and elongation of the tubule are driven by a buildup of osmotic potential in the capsule. We question this explanation using a microfluidic system that controls the osmotic potential by directing the tubule through oil, where no osmotic potential can develop, while keeping the capsule in water. It was found that the time needed for elongation through oil is orders of magnitude larger than through water. Our mathematical model shows that the p γGlu concentration in the tubule is higher than in the capsule and the internal pressure that develops there serves as the elongation driving force. These findings imply that modifications of the environment along the tubule route have the potential to slow down the process and reduce its impact. This may shed light on prey defense strategies, human protection against jellyfish stinging, the use of nematocysts for drug delivery and exploration of osmotic based methods for nanotubes production and elongation.

Case report of jelly fish stinging in Bay of Bengal: A report from Bangladesh

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Mohammad Main Uddin

2016-08-01

Full Text Available Introduction: Jelly fish or jellies are the members of the phylum Cnidaria (Coelenterata, consisting of a gelatinous umbrella-shaped bell and trailing tentacles. Sting contains toxic peptide, pbospholipase A and histamine-liberating factor. Jelly fish stinging in Bangladesh is rare. Yet, from a management point of view, this epizoonozis might gain importance given the ever-growing popularity of seaside fishering and tourism. We are presenting a case of jelly fish contact illness in Cox's Bazar Medical College. Case Report: A 30 year old male patient was stung by a jellyfish while tishering in the Bay of Bengal near Teknaf of Cox's Bazar District on 3rd June' 2013. A couple of minutes later urticaria were formed in the contact area accompanied by a bmniug and sore sensation. Within few minutes be developed severe abdominal pain, bodyache and parestbaesia. Immediate decontmninalion was done by patient himself with sea water though ideally it should be with 5% acetic acid. Routine laboratory investigations show no abnormality except non-significant ST elevation in ECG. The patient was managed conservatively with antihistamine, corticosteroids and antibiotics and recovered completely within four days.

The Global Invertebrate Genomics Alliance (GIGA): Developing Community Resources to Study Diverse Invertebrate Genomes

KAUST Repository

Bracken-Grissom, Heather

2013-12-12

Over 95% of all metazoan (animal) species comprise the invertebrates, but very few genomes from these organisms have been sequenced. We have, therefore, formed a Global Invertebrate Genomics Alliance (GIGA). Our intent is to build a collaborative network of diverse scientists to tackle major challenges (e.g., species selection, sample collection and storage, sequence assembly, annotation, analytical tools) associated with genome/transcriptome sequencing across a large taxonomic spectrum. We aim to promote standards that will facilitate comparative approaches to invertebrate genomics and collaborations across the international scientific community. Candidate study taxa include species from Porifera, Ctenophora, Cnidaria, Placozoa, Mollusca, Arthropoda, Echinodermata, Annelida, Bryozoa, and Platyhelminthes, among others. GIGA will target 7000 noninsect/nonnematode species, with an emphasis on marine taxa because of the unrivaled phyletic diversity in the oceans. Priorities for selecting invertebrates for sequencing will include, but are not restricted to, their phylogenetic placement; relevance to organismal, ecological, and conservation research; and their importance to fisheries and human health. We highlight benefits of sequencing both whole genomes (DNA) and transcriptomes and also suggest policies for genomic-level data access and sharing based on transparency and inclusiveness. The GIGA Web site () has been launched to facilitate this collaborative venture.

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.

Exploring the genetic diversity of shallow-water Agariciidae (Cnidaria: Anthozoa) from the Saudi Arabian Red Sea

KAUST Repository

Terraneo, Tullia Isotta; Arrigoni, Roberto; Benzoni, Francesca; Tietbohl, Matthew; Berumen, Michael L.

2017-01-01

Scleractinian corals ascribed to the family Agariciidae represent an important component of Red Sea coral reef fauna, though little genetic data are currently available for this group, and existing information shows polyphyly in the examined mesophotic taxa from the Pacific Ocean. In this work, we provide a first genetic survey of Agariciidae from the Saudi Arabian Red Sea, based on a collection of shallow-water material (<30 m) from the Gulf of Aqaba to the Farasan Islands. Two molecular markers were sequenced to infer morphospecies monophyly and relationships, the intergenic region between COI and 16S rRNA from mitochondrial DNA and the ribosomal ITS1 region from nuclear DNA. A total of 20 morphospecies were identified based on classical macromorphological characters. Six, namely Gardineroseris planulata, Pavona maldivensis, Pavona clavus, Pavona decussata, Leptoseris fragilis, and Leptoseris yabei, were resolved with both DNA loci. The molecular boundaries among the remaining 14 species remain unclear. Our results further confirm that the morphology-based taxonomy of most agariciid species is in disagreement with genetics. In order to disentangle the systematics of these taxa, the inclusion of more sampling locations, additional variable loci, and a micromophological approach are likely needed. Our genetic data represent a first step towards the comparison of biodiversity and connectivity between the Red Sea and the rest of the Indo-Pacific.

Octocorallia (Cnidaria: Anthozoa) from the Scotia Arc, South Atlantic Ocean. I. The genus Alcyonium Linnaeus, 1758

NARCIS (Netherlands)

Casas, C.; Ramil, F.; Ofwegen, van L.P.

1997-01-01

Three new species of Alcyonium collected by the Spanish Antarctic Expeditions "Antártida 8611" and "Bentart 95" are described and figured: Alcyonium paucilobulatum, A. grandis and A. southgeorgiensis. Another two species, A. antarcticum Wright & Studer, 1889, and Alcyonium sollasi Wright & Studer,

Exploring the genetic diversity of shallow-water Agariciidae (Cnidaria: Anthozoa) from the Saudi Arabian Red Sea

KAUST Repository

Terraneo, Tullia Isotta

2017-05-19

Scleractinian corals ascribed to the family Agariciidae represent an important component of Red Sea coral reef fauna, though little genetic data are currently available for this group, and existing information shows polyphyly in the examined mesophotic taxa from the Pacific Ocean. In this work, we provide a first genetic survey of Agariciidae from the Saudi Arabian Red Sea, based on a collection of shallow-water material (<30 m) from the Gulf of Aqaba to the Farasan Islands. Two molecular markers were sequenced to infer morphospecies monophyly and relationships, the intergenic region between COI and 16S rRNA from mitochondrial DNA and the ribosomal ITS1 region from nuclear DNA. A total of 20 morphospecies were identified based on classical macromorphological characters. Six, namely Gardineroseris planulata, Pavona maldivensis, Pavona clavus, Pavona decussata, Leptoseris fragilis, and Leptoseris yabei, were resolved with both DNA loci. The molecular boundaries among the remaining 14 species remain unclear. Our results further confirm that the morphology-based taxonomy of most agariciid species is in disagreement with genetics. In order to disentangle the systematics of these taxa, the inclusion of more sampling locations, additional variable loci, and a micromophological approach are likely needed. Our genetic data represent a first step towards the comparison of biodiversity and connectivity between the Red Sea and the rest of the Indo-Pacific.

Examination of species boundaries in the Acropora cervicornis group (Scleractinia, cnidaria) using nuclear DNA sequence analyses.

Science.gov (United States)

Oppen, M J; Willis, B L; Vugt, H W; Miller, D J

2000-09-01

Although Acropora is the most species-rich genus of the scleractinian (stony) corals, only three species occur in the Caribbean: A. cervicornis, A. palmata and A. prolifera. Based on overall coral morphology, abundance and distribution patterns, it has been suggested that A. prolifera may be a hybrid between A. cervicornis and A. palmata. The species boundaries among these three morphospecies were examined using DNA sequence analyses of the nuclear Pax-C 46/47 intron and the ribosomal DNA Internal Transcribed Spacer (ITS1 and ITS2) and 5.8S regions. Moderate levels of sequence variability were observed in the ITS and 5.8S sequences (up to 5.2% overall sequence difference), but variability within species was as large as between species and all three species carried similar sequences. Since this is unlikely to represent a shared ancestral polymorphism, the data suggest that introgressive hybridization occurs among the three species. For the Pax-C intron, A. cervicornis and A. palmata had very distinct allele frequencies and A. cervicornis carried a unique allele at a frequency of 0.769 (although sequence differences between alleles were small). All A. prolifera colonies examined were heterozygous for the Pax-C intron, whereas heterozygosity was only 0.286 and 0.333 for A. cervicornis and A. palmata, respectively. These data support the hypothesis that A. prolifera is the product of hybridization between two species that have a different allelic composition for the Pax-C intron, i.e. A. cervicornis and A. palmata. We therefore suggest that A. prolifera is a hybrid between A. cervicornis and A. palmata, which backcrosses with the parental species at low frequency.

High in situ repeatability of behaviour indicates animal personality in the beadlet anemone Actinia equina (Cnidaria.

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Mark Briffa

Full Text Available 'Animal personality' means that individuals differ from one another in either single behaviours or suites of related behaviours in a way that is consistent over time. It is usually assumed that such consistent individual differences in behaviour are driven by variation in how individuals respond to information about their environment, rather than by differences in external factors such as variation in microhabitat. Since behavioural variation is ubiquitous in nature we might expect 'animal personality' to be present in diverse taxa, including animals with relatively simple nervous systems. We investigated in situ startle responses in a sea anemone, Actinia equina, to determine whether personalities might be present in this example of an animal with a simple nervous system. We found very high levels of repeatability among individuals that were re-identified in the same locations over a three week sampling period. In a subset of the data, where we used tide-pool temperature measurements to control for a key element of variation in microhabitat, these high levels of repeatability remained. Although a range of other consistent differences in micro-habitat features could have contributed to consistent differences between the behaviour of individuals, these data suggest the presence of animal personality in A. equina. Rather than being restricted to certain groups, personality may be a general feature of animals and may be particularly pronounced in species with simple nervous systems.

Revisiting the phylogeny of Zoanthidea (Cnidaria: Anthozoa): Staggered alignment of hypervariable sequences improves species tree inference.

Science.gov (United States)

Swain, Timothy D

2018-01-01

The recent rapid proliferation of novel taxon identification in the Zoanthidea has been accompanied by a parallel propagation of gene trees as a tool of species discovery, but not a corresponding increase in our understanding of phylogeny. This disparity is caused by the trade-off between the capabilities of automated DNA sequence alignment and data content of genes applied to phylogenetic inference in this group. Conserved genes or segments are easily aligned across the order, but produce poorly resolved trees; hypervariable genes or segments contain the evolutionary signal necessary for resolution and robust support, but sequence alignment is daunting. Staggered alignments are a form of phylogeny-informed sequence alignment composed of a mosaic of local and universal regions that allow phylogenetic inference to be applied to all nucleotides from both hypervariable and conserved gene segments. Comparisons between species tree phylogenies inferred from all data (staggered alignment) and hypervariable-excluded data (standard alignment) demonstrate improved confidence and greater topological agreement with other sources of data for the complete-data tree. This novel phylogeny is the most comprehensive to date (in terms of taxa and data) and can serve as an expandable tool for evolutionary hypothesis testing in the Zoanthidea. Spanish language abstract available in Text S1. Translation by L. O. Swain, DePaul University, Chicago, Illinois, 60604, USA. Copyright © 2017 Elsevier Inc. All rights reserved.

Taxonomic redescription of the Portuguese man-of-war, Physalia physalis (Cnidaria, Hydrozoa, Siphonophorae, Cystonectae from Brazil Redescrição taxonômica da caravela-do-mar, Physalia physalis (Cnidaria, Hydrozoa, Siphonophorae, Cystonectae do litoral do Brasil

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Juliana Bardi

2007-12-01

Full Text Available Although Physalia physalis (Linnaeus, 1758 is widely known from the Brazilian waters, specimens from this coast were never properly described. We describe Brazilian specimens of P. physalis including information on morphology, cnidome, SEM, and histological studies. Taxonomical issues concerning the development of the colonies and eventual synonymy with Physalia utriculus (La Martinière, 1787 are also added.Physalia physalis (Linnaeus, 1758 é amplamente conhecida em águas brasileiras, mas os espécimes dessa costa nunca foram formalmente descritos. Descrevem-se os espécimes brasileiros, adicionando-se informações sobre a morfologia, cnidoma, MEV e histologia. Questões taxonômicas que envolvem o desenvolvimento das colônias e a eventual sinonímia com Physalia utriculus (La Martinière, 1787 também são abordadas.

DNA barcoding commercially important aquatic invertebrates of Turkey.

Science.gov (United States)

Keskin, Emre; Atar, Hasan Hüseyin

2013-08-01

DNA barcoding was used in order to identify aquatic invertebrates sampled from fisheries bycatch and discards. A total of 440 unique cytochrome c oxidase sub unit I (COI) barcodes were generated for 22 species from three important phyla (Arthropoda, Cnidaria, and Mollusca). All the species were sequenced and submitted to GenBank and Barcode of Life Database (BOLD) databases using 654 bp-long fragment of mitochondrial COI gene. Two of them (Pontastacus leptodactylus and Rapana bezoar) were first records of the species for the BOLD database and six of them (Carcinus aestuarii, Loligo vulgaris, Melicertus kerathurus, Nephrops norvegicus, Scyllarides latus, and Scyllarus arctus) were first standard (>648 bp) COI barcode records for the GenBank database. COI barcodes were analyzed for nucleotide composition, nucleotide pair frequencies, and Kimura's two-parameter genetic distance. Mean genetic distance among species was found increasing at higher taxonomic levels. Neighbor-joining trees generated were congruent with morphometric-based taxonomic classification. Findings of this study clearly demonstrate that DNA barcodes could be used as an efficient molecular tool in identification of not only target species from fisheries but also bycatch and discard species, and so it could provide us leverage for a better understanding in monitoring and management of fisheries and biodiversity.

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

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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.

Impact of Amorphous Silica Nanoparticles on a Living Organism: Morphological, Behavioural and Molecular Biology Implications.

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Alfredo eAmbrosone

2014-09-01

Full Text Available It is generally accepted that silica (SiO2 is not toxic. But the increasing use of silica nanoparticles (SiO2NPs in many different industrial fields has prompted the careful investigation of its toxicity in biological systems. In this report, we describe the effects elicited by SiO2NPs on animal and cell physiology. Stable and monodisperse amorphous silica nanoparticles 25nm in diameter, were administered to living Hydra vulgaris (Cnidaria. The dose-related effects were defined by morphological and behavioural assays. The results revealed an all-or-nothing lethal toxicity with a rather high threshold (35nM NPs and a LT50 of 38h. At sub lethal doses the morpho-physiological effects included: animal morphology alterations, paralysis of the gastric region, disorganization and depletion of tentacle specialized cells, increase of apoptotic and collapsed cells and reduction of the epithelial cell proliferation rate. Transcriptome analysis (RNAseq revealed 45 differentially expressed genes, mostly involved in stress response and cuticle renovation. Our results show that Hydra reacts to SiO2NPs, is able to rebalance the animal homeostasis up to a relatively high doses of SiO2NPs and that the physiological modifications are transduced to gene expression modulation.

Neurotoxin localization to ectodermal gland cells uncovers an alternative mechanism of venom delivery in sea anemones.

Science.gov (United States)

Moran, Yehu; Genikhovich, Grigory; Gordon, Dalia; Wienkoop, Stefanie; Zenkert, Claudia; Ozbek, Suat; Technau, Ulrich; Gurevitz, Michael

2012-04-07

Jellyfish, hydras, corals and sea anemones (phylum Cnidaria) are known for their venomous stinging cells, nematocytes, used for prey and defence. Here we show, however, that the potent Type I neurotoxin of the sea anemone Nematostella vectensis, Nv1, is confined to ectodermal gland cells rather than nematocytes. We demonstrate massive Nv1 secretion upon encounter with a crustacean prey. Concomitant discharge of nematocysts probably pierces the prey, expediting toxin penetration. Toxin efficiency in sea water is further demonstrated by the rapid paralysis of fish or crustacean larvae upon application of recombinant Nv1 into their medium. Analysis of other anemone species reveals that in Anthopleura elegantissima, Type I neurotoxins also appear in gland cells, whereas in the common species Anemonia viridis, Type I toxins are localized to both nematocytes and ectodermal gland cells. The nematocyte-based and gland cell-based envenomation mechanisms may reflect substantial differences in the ecology and feeding habits of sea anemone species. Overall, the immunolocalization of neurotoxins to gland cells changes the common view in the literature that sea anemone neurotoxins are produced and delivered only by stinging nematocytes, and raises the possibility that this toxin-secretion mechanism is an ancestral evolutionary state of the venom delivery machinery in sea anemones.

Sterol patterns of cultured zooxanthellae isolated from marine invertebrates: Synthesis of gorgosterol and 23-desmethylgorgosterol by aposymbiotic algae.

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Withers, N W; Kokke, W C; Fenical, W; Djerassi, C

1982-06-01

QUANTITATIVE STEROL COMPOSITIONS OF CULTURED ZOOXANTHELLAE ISOLATED FROM VARIOUS PACIFIC AND ATLANTIC INVERTEBRATE HOSTS: Zoanthus sociatus (a zoanthid), Oculina diffusa (a scleractian coral), Tridacna gigas (a giant clam), Melibe pilosa (a nudibranch), and Aiptasia pulchella (a sea anemone) are reported. The results clearly demonstrate large differences in sterol patterns of zooxanthellae and that there is no obvious relationship between the taxonomic affiliation of the host and the sterol pattern of its isolated symbiont. The sterols of the zooxanthellae of O. diffusa (Cnidaria) and T. gigas (Mollusca) are qualitatively equivalent. Based on the structures of the two major free sterols synthesized by each alga, the zooxanthellae from different hosts were separated into three distinct groups. It was also found that an aposymbiotic alga can synthesize the unique marine sterols gorgosterol and 23-desmethylgorgosterol. Most of the sterols were identified by using mass spectroscopy and 360-MHz proton magnetic resonance. Spectroscopic data are reported for four novel sterols-(23,24R)-dimethyl-5alpha-cholest-(22E)-en-3beta-o l, 23-methyl-5alpha-cholest-22E-en-3beta-ol, cholesta-5,14-dien-3beta-ol, and 4alpha-methyl-5alpha-cholesta-8(14)-24-dien-3beta-ol.

Structural analysis of the α subunit of Na(+)/K(+) ATPase genes in invertebrates.

Science.gov (United States)

Thabet, Rahma; Rouault, J-D; Ayadi, Habib; Leignel, Vincent

2016-01-01

The Na(+)/K(+) ATPase is a ubiquitous pump coordinating the transport of Na(+) and K(+) across the membrane of cells and its role is fundamental to cellular functions. It is heteromer in eukaryotes including two or three subunits (α, β and γ which is specific to the vertebrates). The catalytic functions of the enzyme have been attributed to the α subunit. Several complete α protein sequences are available, but only few gene structures were characterized. We identified the genomic sequences coding the α-subunit of the Na(+)/K(+) ATPase, from the whole-genome shotgun contigs (WGS), NCBI Genomes (chromosome), Genomic Survey Sequences (GSS) and High Throughput Genomic Sequences (HTGS) databases across distinct phyla. One copy of the α subunit gene was found in Annelida, Arthropoda, Cnidaria, Echinodermata, Hemichordata, Mollusca, Placozoa, Porifera, Platyhelminthes, Urochordata, but the nematodes seem to possess 2 to 4 copies. The number of introns varied from 0 (Platyhelminthes) to 26 (Porifera); and their localization and length are also highly variable. Molecular phylogenies (Maximum Likelihood and Maximum Parsimony methods) showed some clusters constituted by (Chordata/(Echinodermata/Hemichordata)) or (Plathelminthes/(Annelida/Mollusca)) and a basal position for Porifera. These structural analyses increase our knowledge about the evolutionary events of the α subunit genes in the invertebrates. Copyright © 2016 Elsevier Inc. All rights reserved.

Dermatology in the Darwin anniversary. Part 1: Evolution of the integument.

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Schempp, Christoph; Emde, Matthias; Wölfle, Ute

2009-09-01

The present review highlights the development of the integument and its adnexa from the primitive metazoans to man. The different stages of development represent independent, partially convergent evolutions rather than a continuous evolutionary line. The epidermis of the invertebrates (sponges, cnidaria, worms, echinoderms and arthropods) always consists of one layer of pluripotent cells. The barrier function of the integument at this level is achieved with physico-chemical barriers, toxin production, fortification of the epidermis in the form of a cuticula, a syncytium or a neodermis. The lower vertebrates (cyclostoma, fishes and amphibians) have a stratified epidermis harboring many secretory cells. In terrestrial amphibians the outermost cell layer of the epidermis is cornified, and the secretory cells are relocated in the dermis. Terminal differentiation and cornification of the epidermis in the birds and mammals result in a more uniform shape of the epithelium. Stem cells are now restricted to some basal regions of the epithelium. In the mammals the glands are located in the deeper layers of the skin. In contrast to other vertebrate integuments the human skin does not possess specialized structures such as feathers, scales or coats. However, waiving specialization allows for unique universality of the human skin compared to other vertebrates.

Impact of Amorphous SiO{sub 2} Nanoparticles on a Living Organism: Morphological, Behavioral, and Molecular Biology Implications

Energy Technology Data Exchange (ETDEWEB)

Ambrosone, Alfredo; Scotto di Vettimo, Maria Rosaria [Istituto di Cibernetica “Eduardo Caianiello”, Consiglio Nazionale delle Ricerche, Pozzuoli (Italy); Malvindi, Maria Ada [Center for Biomolecular Nanotechnologies@UNILE, Istituto Italiano di Tecnologia, Arnesano (Italy); Roopin, Modi; Levy, Oren [The Mina and Everard Goodman Faculty of Life Sciences, Bar Ilan University, Ramat Gan (Israel); Marchesano, Valentina [Istituto di Cibernetica “Eduardo Caianiello”, Consiglio Nazionale delle Ricerche, Pozzuoli (Italy); Pompa, Pier Paolo [Center for Biomolecular Nanotechnologies@UNILE, Istituto Italiano di Tecnologia, Arnesano (Italy); Tortiglione, Claudia; Tino, Angela, E-mail: a.tino@cib.na.cnr.it [Istituto di Cibernetica “Eduardo Caianiello”, Consiglio Nazionale delle Ricerche, Pozzuoli (Italy)

2014-09-29

It is generally accepted that silica (SiO{sub 2}) is not toxic. But the increasing use of silica nanoparticles (SiO{sub 2}NPs) in many different industrial fields has prompted the careful investigation of their toxicity in biological systems. In this report, we describe the effects elicited by SiO{sub 2}NPs on animal and cell physiology. Stable and monodisperse amorphous silica nanoparticles, 25 nM in diameter, were administered to living Hydra vulgaris (Cnidaria). The dose-related effects were defined by morphological and behavioral assays. The results revealed an all-or-nothing lethal toxicity with a rather high threshold (35 nM NPs) and a LT50 of 38 h. At sub lethal doses, the morphophysiological effects included: animal morphology alterations, paralysis of the gastric region, disorganization and depletion of tentacle specialized cells, increase of apoptotic and collapsed cells, and reduction of the epithelial cell proliferation rate. Transcriptome analysis (RNAseq) revealed 45 differentially expressed genes, mostly involved in stress response and cuticle renovation. Our results show that Hydra reacts to SiO{sub 2}NPs, is able to rebalance the animal homeostasis up to a relatively high doses of SiO{sub 2}NPs, and that the physiological modifications are transduced to gene expression modulation.

Sea Water Acidification Affects Osmotic Swelling, Regulatory Volume Decrease and Discharge in Nematocytes of the Jellyfish Pelagia noctiluca

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Rossana Morabito

2013-12-01

Full Text Available Background: Increased acidification/PCO2 of sea water is a threat to the environment and affects the homeostasis of marine animals. In this study, the effect of sea water pH changes on the osmotic phase (OP, regulatory volume decrease (RVD and discharge of the jellyfish Pelagia noctiluca (Cnidaria, Scyphozoa nematocytes, collected from the Strait of Messina (Italy, was assessed. Methods: Isolated nematocytes, suspended in artificial sea water (ASW with pH 7.65, 6.5 and 4.5, were exposed to hyposmotic ASW of the same pH values and their osmotic response and RVD measured optically in a special flow through chamber. Nematocyte discharge was analyzed in situ in ASW at all three pH values. Results: At normal pH (7.65, nematocytes subjected to hyposmotic shock first expanded osmotically and then regulated their cell volume within 15 min. Exposure to hyposmotic ASW pH 6.5 and 4.5 compromised the OP and reduced or totally abrogated the ensuing RVD, respectively. Acidic pH also significantly reduced the nematocyte discharge response. Conclusion: Data indicate that the homeostasis and function of Cnidarians may be altered by environmental changes such as sea water acidification, thereby validating their use as novel bioindicators for the quality of the marine environment.

Sea water acidification affects osmotic swelling, regulatory volume decrease and discharge in nematocytes of the jellyfish Pelagia noctiluca.

Science.gov (United States)

Morabito, Rossana; Marino, Angela; Lauf, Peter K; Adragna, Norma C; La Spada, Giuseppa

2013-01-01

Increased acidification/PCO2 of sea water is a threat to the environment and affects the homeostasis of marine animals. In this study, the effect of sea water pH changes on the osmotic phase (OP), regulatory volume decrease (RVD) and discharge of the jellyfish Pelagia noctiluca (Cnidaria, Scyphozoa) nematocytes, collected from the Strait of Messina (Italy), was assessed. Isolated nematocytes, suspended in artificial sea water (ASW) with pH 7.65, 6.5 and 4.5, were exposed to hyposmotic ASW of the same pH values and their osmotic response and RVD measured optically in a special flow through chamber. Nematocyte discharge was analyzed in situ in ASW at all three pH values. At normal pH (7.65), nematocytes subjected to hyposmotic shock first expanded osmotically and then regulated their cell volume within 15 min. Exposure to hyposmotic ASW pH 6.5 and 4.5 compromised the OP and reduced or totally abrogated the ensuing RVD, respectively. Acidic pH also significantly reduced the nematocyte discharge response. Data indicate that the homeostasis and function of Cnidarians may be altered by environmental changes such as sea water acidification, thereby validating their use as novel bioindicators for the quality of the marine environment. © 2014 S. Karger AG, Basel.

First report on large scleractinian (Cnidaria: Anthozoa) accumulations in cold-temperate shallow water of south Chilean fjords

NARCIS (Netherlands)

Försterra, G.; Häussermann, V.

2003-01-01

South Chilean fjords contain an astonishing diverse benthic macrofauna of which anthozoans form a major portion. Azooxanthellate solitary scleractinians, which were hitherto known from major depths, were found as shallow as 8 m during several expeditions to the south Chilean fjord region. At some

Cyphastrea kausti sp. n. (Cnidaria, Anthozoa, Scleractinia), a new species of reef coral from the Red Sea

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Bouwmeester, Jessica; Benzoni, Francesca; Baird, Andrew H.; Berumen, Michael L.

2015-01-01

Abstract A new scleractinian coral species, Cyphastrea kausti sp. n., is described from 13 specimens from the Red Sea. It is characterised by the presence of eight primary septa, unlike the other species of the genus, which have six, ten or 12 primary septa. The new species has morphological affinities with Cyphastrea microphthalma, from which it can be distinguished by the lower number of septa (on average eight instead of ten), and smaller calices and corallites. This species was observed in the northern and central Red Sea and appears to be absent from the southern Red Sea. PMID:25931952

Some Hydroids (Cnidaria, Hydrozoa) from the Great Australian Bight in the collection of the South Australian Museum.

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Watson, Jeanette E

2018-04-16

This report adds to knowledge of the shelf hydroid fauna of the Great Australian Bight. Hydroids were collected by the South Australian Museum and Department of Primary Industries of South Australia (PIRSA). Well known species are annotated, poorly known species are redescribed and four new species are described.

Occurrence and biogeography of hydroids (Cnidaria: Hydrozoa) from deep-water coral habitats off the southeastern United States

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Henry, Lea-Anne; Nizinski, Martha S.; Ross, Steve W.

2008-06-01

Deep-water coral habitats off the southeastern USA (SEUS) support diverse fish and invertebrate assemblages, but are poorly explored. This study is the first to report on the hydroids collected from these habitats in this area. Thirty-five species, including two species that are likely new to science, were identified from samples collected primarily by manned submersible during 2001-2005 from deep-water coral habitats off North Carolina to east-central Florida. Eleven of the species had not been reported since the 19th to mid-20th century. Ten species, and one family, the Rosalindidae, are documented for the first time in the SEUS. Latitudinal ranges of 15 species are extended, and the deepest records in the western North Atlantic for 10 species are reported. A species accumulation curve illustrated that we continue to add to our knowledge of hydroid diversity in these habitats. Sexually mature individuals were collected for 19 species during the summer to early autumn months. Most of the observed species (89%) liberate planula larvae as part of their life cycles, suggesting that these species exhibit a reproductive strategy that reduces the risk of dispersal to sub-optimal habitats. Hydroids occurred across various substrata including coral rubble, live corals, rock and other animal hosts including hydroids themselves. All observed species were regionally widespread with typically deep-neritic to bathyal sub-tropical/tropical distributions. Hydroid assemblages from deep-water SEUS coral habitats were most similar to those from adjacent deep-water habitats off the SEUS (17 shared species), and those in the Straits of Florida/Bahamas and Caribbean/West Indian regions (14 and 8 shared species, respectively). The similarity to sub-tropical and tropical assemblages and the richness of plumularioids in the SEUS deep-water coral habitats support the idea of a Pleistocene intrusion of tropical species northwards following an intensification of the Gulf Stream from the Caribbean.

Cyphastrea kausti sp. n. (Cnidaria, Anthozoa, Scleractinia), a new species of reef coral from the Red Sea

KAUST Repository

Bouwmeester, Jessica

2015-04-16

A new scleractinian coral species, Cyphastrea kausti sp. n., is described from 13 specimens from the Red Sea. It is characterised by the presence of eight primary septa, unlike the other species of the genus, which have six, ten or 12 primary septa. The new species has morphological affinities with Cyphastrea microphthalma, from which it can be distinguished by the lower number of septa (on average eight instead of ten), and smaller calices and corallites. This species was observed in the northern and central Red Sea and appears to be absent from the southern Red Sea.

Using hydrofluoric acid for morphological investigations of Zoanthids (Cnidaria: Anthozoa): a critical assessment of methodology and necessity.

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Reimer, James Davis; Nakachi, Shu; Hirose, Mamiko; Hirose, Euichi; Hashiguchi, Shinji

2010-10-01

Zoanthids comprise an order of benthic, generally colonial cnidarians, which can usually be distinguished from other hexacorallians by embedded sand and detritus in their mesoglea to help strengthen their structure. These animals are becoming increasingly important research subjects in biochemistry and other research fields. Their inclusion of both calcium and silica results in the need for both decalcification and desilification for internal morphological examinations. Since the methodology of hydrofluoric acid (HF) desilification has rarely been documented in zoanthids, histological surveys for zoanthid taxonomy have often been abandoned and their taxonomy is often problematic. Recent investigations utilizing molecular methods have brought a clearer understanding of zoanthid diversity, but standardization of HF treatments are still needed to provide a link between molecular and more traditional techniques, and to properly examine specimens for which molecular methods may not be an option (e.g., formalin-preserved specimens, etc.). Here, we use both "straight" HF and, for the first time with zoanthids, buffered HF (BHF) treatments at different treatment lengths (1-48 h) on polyps from three different species of zoanthids for histological examination. Section conditions were judged based on the presence/absence of embedded detritus, drag marks, and tissue condition. Results show that the BHF treatment resulted in slightly better tissue conditions for all specimens, and suggest that desilification works well regardless of treatment time for species with smaller (polyp diameter zoanthid specimens.

Reproductive biology of Palythoa caribaeorum and Protopalythoa valilbilis (Cnidaria, Anthozoa, Zoanthidea) from the southeastern coast of Brazil.

Science.gov (United States)

Boscolo, H K; Silveira, F L

2005-02-01

The reproductive biology of Palythoa caribaeorum (Duchassaing & Michelotti 1860) and Protopalythoa variabilis (Duerden 1898) was studied through monthly samples from tagged colonies from June 1996 to June 1997, in Sao Sebastiao channel, São Paulo, Brazil (45 degrees 26'W, 23 degrees 50'S). The gametogenesis was similar to that of other zoanthids as shown by histological preparations. Oocyte diameters and maturation stages of testis vesicles were evaluated on squash preparations. Both species showed sequential protogynic hermaphroditism, with high frequency of fertile polyps (83% in P. variabilis and 72% in P. caribaeorun), high frequency of colonies in female sex condition (65.3% of P variabilis and 41.7% of P caribaeorum), and apparently continuous gametogenesis. In P. caribaribaeonrum, egg release was continuous and sperm release took place during half of the analyzed period. In P. variabilis, egg and sperm release occurred in April-May and February-March 1997, respectively.

INTERSPECIFIC AGGRESSIVE BEHAVIOR OF THE CORALLIMORPHARIAN CORYNACTIS CALIFORNICA (CNIDARIA: ANTHOZOA): EFFECTS ON SYMPATRIC CORALS AND SEA ANEMONES.

Science.gov (United States)

Chadwick, Nanette E

1987-08-01

Corallimorpharians are sessile cnidarians that are morphologically similar to the actiniarian sea anemones and scleractinian corals. This study describes for the first time the behavioral mechanism and effects of aggression by a corallimorpharian. Polyps of the temperate clonal corallimorpharian Corynactis californica extruded their mesenteries and associated filaments onto members of certain species of sea anemones and corals. They did not exhibit this behavior intraspecifically, and members of different clones of C. californica remained expanded upon contact. In contrast, members of four species of corals and zoanthids responded to contact with C. californica by contracting their tentacles, and members of three sea anemone species bent or moved away, detached from the substrate, or attacked using their aggressive structures. When interspecific contact was prolonged, individuals of C. californica extruded filaments onto, and killed polyps of, the sea anemones Anthopleura elegantissima and Metridium senile within 3 weeks, and the corals Astrangia lajollaensis and Balanophyllia elegans within 4-10 months under laboratory conditions. The use of extruded mesenterial filaments by C. californica to attack members of other anthozoan species is similar to the aggressive behavior exhibited by many scleractinian reef corals. Field observations suggest that C. californica may use this agonistic behavior during interspecific competition for space on hard marine substrate.

Environmental control of asexual reproduction and somatic growth of Aurelia spp. (Cnidaria, Scyphozoa) polyps from the Adriatic Sea

OpenAIRE

Hubot, Nathan; Lucas, Cathy H.; Piraino, Stefano

2017-01-01

Polyps of two moon jellyfish species, Aurelia coerulea and A.relicta, from two Adriatic Sea coastal habitats were incubated under multiple combinations of temperature (14, 21 °C), salinity (24, 37 ppt) and food regime (9.3, 18.6, 27.9 μg C ind‾¹ week‾¹) to comparatively assess how these factors may influence major asexual reproduction processes in the two species. Both species exhibited a shared pattern of budding mode (Directly Budded Polyps: DBP; Stolonal Budded Polyps: SBP), with DBP favo...

Deep-water scleractinian corals (Cnidaria: Anthozoa) from 2010-2011 INDEMARES expeditions to the Galicia Bank (Spain, northeast Atlantic).

Science.gov (United States)

Altuna, Alvaro

2017-11-23

During surveys in the Galicia Bank (northeastern Atlantic) in the years 2010-2011 (INDEMARES project), 25 species of scleractinian corals corals were collected in a depth interval of 744-1764 m. Most interesting species are described and depicted. Additionally, species list and remarks are given for the 23 species dredged in the bank during the 1987 SEAMOUNT 1 expedition at 675-1125 m depth.From a literature review and new records from Galicia Bank given herein, 31 species of scleractinian corals are known from this seamount in a depth interval of 614-1764 m depth. Six are colonial and 25 solitary, with 17 occurring on hard bottoms and 14 on soft bottoms. Desmophyllum dianthus, Lophelia pertusa and Madrepora oculata are the most widely distributed species in both number of stations and depth range of specimens collected alive. Some species were recorded outside their previously known bathymetric ranges in the northeastern Atlantic. Javania pseudoalabastra is first documented for the Iberian Peninsula and Spanish faunas. Thrypticotrochus sp. is first collected from the Atlantic Ocean.

Medusas (Cnidaria: Hydrozoa de una zona de afloramiento costero, Bahía Culebra, Pacífico, Costa Rica

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Karina Rodríguez-Sáenz

2012-12-01

Full Text Available Las hidromedusas tienen un papel importante en redes tróficas marinas debido a sus hábitos alimenticios depredadores. Este es el primer estudio de este grupo del zooplancton gelatinoso en un area de afloramiento costero en América Central. Durante seis meses de 1999, se estudió la abundancia de hidromedusas en cuatro estaciones en Bahía Culebra, Golfo de Papagayo, costa Pacífica de Costa Rica (10º 37’N-85º40’W. Se identificó un total de 53 especies de las que 26 son registros nuevos para Costa Rica, 21 son registros nuevos para América Central y 8 son nuevos registros para el Pacífico Oriental Tropical. Las especies más abundantes durante el estudio (con más de 30% de la abundancia total fueron Liriope tetraphylla, Solmundella bitentaculata y Aglaura hemistoma. Seis especies se presentaron en todos los muestreos, 10 especies se presentaron únicamente durante la época seca y 17 se presentaron únicamente durante la época lluviosa. Se mostraron diferencias significativas entre las épocas lluviosa y seca. La máxima abundancia promedio de hidromedusas (2.1±4.3 ind./m³ fue encontrada durante las fechas que se espera el afloramiento costero, indicado por alta concentración de oxígeno y baja temperatura. La rica composición de especies encontrada en Bahía Culebra puede ser el resultado de varios factores, incluyendo la condición prístina de la bahía, el transporte de especies por la Contra Corriente Nor-Ecuatorial (NECC y los aportes de origen terrestre. Se incluyen ilustraciones de las 15 especies más importantes para facilitar su identificación y promover estudios futuros en la región.

Two new species of Dendrobrachia Brook, 1889 (Cnidaria: Octocorallia: Dendrobrachiidae from the north-eastern Atlantic and western Mediterranean

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Pablo J. López-González

2010-08-01

Full Text Available Examination of recent benthic material collected during several cruises in the Gulf of Cadiz (NE Atlantic and the Strait of Sicily (Mediterranean has allowed the taxonomic reassessment of some previously identified specimens belonging to the monogeneric gorgonian family Dendrobrachiidae Brook, 1889. Dendrobrachia fallax Brook, 1889 is the type species of the single genus in this family, and was originally described from Ascension Island (South Atlantic. Subsequently, other authors reported the presence of this species in Cape Verde Islands (north-eastern Atlantic and some Mediterranean localities (Alboran Sea and the Strait of Sicily. The study of the specimen from the Prince of Monaco collections in Cape Verde Islands, and recently collected material from the Gulf of Cadiz (north-eastern Atlantic and in the south of Malta (Mediterranean, materials previously considered as D. fallax, allow us to recognize two undescribed species in this genus. All previous records of D. fallax from the north-eastern Atlantic and Mediterranean should be considered incorrect. Opresko and Bayer (1991 added two additional species of Dendrobrachia. Two new species are described here and compared with their congeners.

Oculogryphus chenghoiyanae sp. n. (Coleoptera, Lampyridae: a new ototretine firefly from Hong Kong with descriptions of its bioluminescent behavior and ultraviolet-induced fluorescence in females

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Vor Yiu

2018-02-01

Full Text Available The first Oculogryphus species with associated males and female was found in Hong Kong and is described as new: O. chenghoiyanae sp. n. Adults of both sexes were collected live in the field and their bioluminescent behavior is reported for the first time in the genus. The captive males emit weak and continuous light from a pair of light spots on abdominal ventrite 6 or do so when disturbed. The larviform (highly paedomorphic females can glow brightly from a pair of light-emitting organs on the abdomen. The females of Oculogryphus and Stenocladius are to date the only documented representatives of paedomorphism in ototretine fireflies. The finding is consistent with the evidence from male morphology and bioluminescent behavior, supporting the close relationship between the two genera. A key to the Oculogryphus species is provided. The Oculogryphus females can fluoresce with a blue-green light through the whole body under ultraviolet illumination, a phenomenon reported in the Lampyridae for the first time. The co-occurrence of bioluminescence and fluorescence is rare in terrestrial ecosystems, previously known only in some millipedes (Diplopoda. The fluorescence and bioluminescence abilities of Oculogryphus females are functionally independent: abdominal light-emitting organs producing bright yellowish green light while the body wall fluoresces with blue-green light. In contrast, fluorescence and bioluminescence in millipedes are biochemically linked, like in some jellyfish (Cnidaria: Medusozoa.

Transcriptome analysis of the scleractinian coral Stylophora pistillata.

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Sarit Karako-Lampert

Full Text Available The principal architects of coral reefs are the scleractinian corals; these species are divided in two major clades referred to as "robust" and "complex" corals. Although the molecular diversity of the "complex" clade has received considerable attention, with several expressed sequence tag (EST libraries and a complete genome sequence having been constructed, the "robust" corals have received far less attention, despite the fact that robust corals have been prominent focal points for ecological and physiological studies. Filling this gap affords important opportunities to extend these studies and to improve our understanding of the differences between the two major clades. Here, we present an EST library from Stylophora pistillata (Esper 1797 and systematically analyze the assembled transcripts compared to putative homologs from the complete proteomes of six well-characterized metazoans: Nematostella vectensis, Hydra magnipapillata, Caenorhabditis elegans, Drosophila melanogaster, Strongylocentrotus purpuratus, Ciona intestinalis and Homo sapiens. Furthermore, comparative analyses of the Stylophora pistillata ESTs were performed against several Cnidaria from the Scleractinia, Actiniaria and Hydrozoa, as well as against other stony corals separately. Functional characterization of S. pistillata transcripts into KOG/COG categories and further description of Wnt and bone morphogenetic protein (BMP signaling pathways showed that the assembled EST library provides sufficient data and coverage. These features of this new library suggest considerable opportunities for extending our understanding of the molecular and physiological behavior of "robust" corals.

The mitochondrial 60-kDa heat shock protein in marine invertebrates: biochemical purification and molecular characterization.

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Choresh, Omer; Loya, Yossi; Müller, Werner E G; Wiedenmann, Jörg; Azem, Abdussalam

2004-03-01

Sessile marine invertebrates undergo constant direct exposure to the surrounding environmental conditions, including local and global environmental fluctuations that may lead to fatal protein damage. Induction of heat shock proteins (Hsps) constitutes an important defense mechanism that protects these organisms from deleterious stress conditions. In a previous study, we reported the immunological detection of a 60-kDa Hsp (Hsp60) in the sea anemone Anemonia viridis (formerly called Anemonia sulcata) and studied its expression under a variety of stress conditions. In the present study, we show that the sponge Tetilla sp. from tidal habitats with a highly variable temperature regime is characterized by an increased level of Hsp60. Moreover, we show the expression of Hsp60 in various species among Porifera and Cnidaria, suggesting a general importance of this protein among marine invertebrates. We further cloned the hsp60 gene from A viridis, using a combination of conventional protein isolation methods and screening of a complementary deoxyribonucleic acid library by polymerase chain reaction. The cloned sequence (1764 bp) encodes for a protein of 62.8 kDa (588 amino acids). The 62.8-kDa protein, which contains an amino terminal extension that may serve as a mitochondrial targeting signal, shares a significant identity with mitochondrial Hsp60s from several animals but less identity with Hsp60s from either bacteria or plants.

Metazoan meiofauna in deep-sea canyons and adjacent open slopes: A large-scale comparison with focus on the rare taxa

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Bianchelli, S.; Gambi, C.; Zeppilli, D.; Danovaro, R.

2010-03-01

Metazoan meiofaunal abundance, total biomass, nematode size and the richness of taxa were investigated along bathymetric gradients (from the shelf break down to ca. 5000-m depth) in six submarine canyons and on five adjacent open slopes of three deep-sea regions. The investigated areas were distributed along >2500 km, on the Portuguese to the Catalan and South Adriatic margins. The Portuguese and Catalan margins displayed the highest abundances, biomass and richness of taxa, while the lowest values were observed in the Central Mediterranean Sea. The comparison between canyons and the nearby open slopes showed the lack of significant differences in terms of meiofaunal abundance and biomass at any sampling depth. In most canyons and on most slopes, meiofaunal variables did not display consistent bathymetric patterns. Conversely, we found that the different topographic features were apparently responsible for significant differences in the abundance and distribution of the rare meiofaunal taxa (i.e. taxa accounting for Priapulida, Holothuroidea, Ascidiacea and Cnidaria, were encountered exclusively on open slopes, while others (including the Tanaidacea and Echinodea larvae) were found exclusively in canyons sediments. Results reported here indicate that, at large spatial scales, differences in deep-sea meiofaunal abundance and biomass are not only controlled by the available food sources, but also by the region or habitat specific topographic features, which apparently play a key role in the distribution of rare benthic taxa.

Epizoanthus spp. associations revealed using DNA markers: a case study from Kochi, Japan.

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Reimer, James Davis; Hirose, Mamiko; Nishisaka, Taiki; Sinniger, Frederic; Itani, Gyo

2010-09-01

Zoanthids (Cnidaria, Hexacorallia) of the genus Epizoanthus are often found in association with other marine invertebrates, including gastropods and hermit crabs. However, little information exists on the specificity and nature of these associations due to a lack of investigation into Epizoanthus species diversity, and the taxonomy of Epizoanthus is therefore confused. In this study, analyses of morphological data (tentacle number, polyp size, etc) and molecular data (mitochondrial cytochrome oxidase subunit 1 = COI, 16S ribosomal DNA = 16S rDNA) were used to examine Epizoanthus specimens from Tosa Bay, Kochi, Japan. The Epizoanthus specimens were found on both live gastropods (Gemmula unedo) and hermit crabs (Paguristes palythophilus) inhabiting G. unedo and G. cosmoi shells. While morphological analyses did not show clear differences between examined specimens, both COI and mt 16S rDNA clearly divided the specimens into two groups, one associated only with hermit crabs (= Epizoanthus sp. C), and another associated only with living gastropods (= Epizoanthus sp. S). Unexpectedly, DNA sequences from both groups did not match with two previously reported Epizoanthus species from Japan (E. indicus, E. ramosus), indicating they both may be undescribed species. These results highlight the utility of DNA "barcoding" of unknown zoanthids, and will provide a foundation for re-examinations of Epizoanthus species diversity and specificity, which will be critical in understanding the evolution of these unique marine invertebrates.

Reconstructing skeletal fiber arrangement and growth mode in the coral Porites lutea (Cnidaria, Scleractinia: a confocal Raman microscopy study

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G. Nehrke

2012-11-01

Full Text Available Confocal Raman microscopy (CRM mapping was used to investigate the microstructural arrangement and organic matrix distribution within the skeleton of the coral Porites lutea. Relative changes in the crystallographic orientation of crystals within the fibrous fan-system could be mapped, without the need to prepare thin sections, as required if this information is obtained by polarized light microscopy. Simultaneously, incremental growth lines can be visualized without the necessity of etching and hence alteration of sample surface. Using these methods two types of growth lines could be identified: one corresponds to the well-known incremental growth layers, whereas the second type of growth lines resemble denticle finger-like structures (most likely traces of former spines or skeletal surfaces. We hypothesize that these lines represent the outer skeletal surface before another growth cycle of elongation, infilling and thickening of skeletal areas continues. We show that CRM mapping with high spatial resolution can significantly improve our understanding of the micro-structural arrangement and growth patterns in coral skeletons.

Hidden impacts of the Samarco mining waste dam collapse to Brazilian marine fauna - an example from the staurozoans (Cnidaria)

OpenAIRE

Miranda, Lucília Souza; Marques, Antonio Carlos

2016-01-01

The collapse of the Fundão tailings dam at Mariana (State of Minas Gerais, Brazil) started a huge human tragedy and likely the most serious environmental disaster in recent Brazilian history. The dam had contained waste from processing iron ore from mines owned by Samarco, a joint venture company of the Brazilian Vale S.A. and the Anglo-Australian BHP Billiton Ltd. Following ineffective attempts to contain the disaster, after 16 days the mud flood reached the sea, where its impact is expected...

Estudos ecológicos preliminares e caracterização química dos Cnidaria da costa noroeste portuguesa

OpenAIRE

Gadelha, Juliana Rodrigues

2007-01-01

O levantamento de recursos em espécies marinhas em Portugal ainda é incipiente, considerando que este domínio de investigação tem sido amplamente desenvolvido noutros pontos do globo, pescas, química, bioquímica e farmacologia de organismos marinhos, de modo a obter informações sobre a química de produtos naturais e ecologia química de organismos marinhos derivadas destes organismos. São de realçar a importância das defesas químicas para as relações ecológicas de predação, comp...

Glaciambulata neumayeri gen. et sp. nov., a new Antarctic trachymedusa (Cnidaria: Hydrozoa, with a revision of the family Ptychogastriidae

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Horia R. Galea

2016-12-01

Full Text Available A new genus and species of sympagic trachymedusa, Glaciambulata neumayeri gen. et sp. nov., are described based on material from Antarctica. Its generic features are compared to those of its relatives, Ptychogastria Allman, 1878 and Tesserogastria Beyer, 1959, and a review of the family Ptychogastriidae Mayer, 1910, based on literature data, is provided. From this, it results that the poorly-known Pectis antarctica Haeckel, 1879, formerly assigned to Ptychogastria by a number of authors, displays all characters of the contemporary rhopalonematid genus Voragonema Naumov, 1971. It is additionally demonstrated that V. laciniata Bouillon et al., 2001 is coterminous with P. antarctica, a finding that clarifies, 137 years later, the morphology and the taxonomic status of Haeckel’s medusa. In accordance with the Principle of Priority, Pectis is recognized as the valid name of the genus, and Voragonema is assigned to its synonymy. Similarly so, the specific name introduced by Haeckel has priority over laciniata.

Species complexes and phylogenetic lineages of Hoferellus (Myxozoa, Cnidaria) including revision of the genus: A problematic case for taxonomy

Czech Academy of Sciences Publication Activity Database

Alama-Bermejo, Gema; Jirků, Miloslav; Kodádková, Alena; Pecková, Hana; Fiala, Ivan; Holzer, Astrid S.

2016-01-01

Roč. 9, JAN 11 (2016), č. článku 13. ISSN 1756-3305 R&D Projects: GA ČR GBP505/12/G112; GA ČR GAP506/10/2330; GA ČR(CZ) GP14-28784P Grant - others:AV ČR(CZ) M200961205 Institutional support: RVO:60077344 Keywords : Amphibia * Anura * fish * Carassius * Cyprinus carpio * ITS cloning * mode of attachment * Teleostei * ultrastructure Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 3.080, year: 2016

Redescription of Oswaldella antarctica (Jäderholm, 1904) (Cnidaria Hydrozoa) with notes on related species (Notes on Antarctic hydroids, I)

NARCIS (Netherlands)

Peña Cantero, A.L.; Vervoort, W.

1995-01-01

Jäderholm's type of Schizotricha antarctica, collected by the Swedish Antarctic Expedition 1901-1903, is redescribed from a syntype in the collections of the Swedish National Museum, Stockholm. The type lot of that species proved to be composite, the material best resembling Jäderholm's (1904, 1905)

Abundance, size composition and benthic assemblages of two Mediterranean echinoids off the

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Elzahrae Elmasry

2015-12-01

Full Text Available This study is concerned with the variability in abundance, size composition and benthic assemblages of two echinoid species, the common sea urchin Paracentrotus lividus (Lamarck, 1816 and black urchin Arbacia lixula (Linnaeus, 1758 in the Southeastern Mediterranean (SEM along the coast of Alexandria, Egypt. Four seasonal trips were made during the years 2014–2015 covering 55 km of the shore with depths ranging between 3 and 9 m. The sea urchin species composition, density and size structure and distribution were compared. The associated macrobenthic invertebrates with prominent presence and biomass were observed as well as other benthic fauna and flora associations. The present results showed that P. lividus was the dominant echinoid spatially and temporally. A. lixula showed frequent occurrence in Sidi Bishr and Sidi Gaber stations in the spring season. The most dominant size class was the medium to large-sized classes for P. lividus and large-sized classes for A. lixula. The commercial size for the edible P. lividus represented 33% of the sampled population. Furthermore, the most dominant macrobenthic assemblages beside the echinoid population were primarily oysters, sea cucumbers, and mussels. Beside these, assemblage of seaweeds (red, green, brown and crustose algae, Porifera, Cnidaria, Crustacea, other Echinodermata, Bivalvia, Gastropoda, Tunicata, Bryozoa and Annelida were found. The present study shows that the investigated area represents stable habitats for the echinoid population with rich and diversified algal assemblages as well as other potential food resources.

Novel Kunitz-like Peptides Discovered in the Zoanthid Palythoa caribaeorum through Transcriptome Sequencing.

Science.gov (United States)

Liao, Qiwen; Li, Shengnan; Siu, Shirley Weng In; Yang, Binrui; Huang, Chen; Chan, Judy Yuet-Wa; Morlighem, Jean-Étienne R L; Wong, Clarence Tsun Ting; Rádis-Baptista, Gandhi; Lee, Simon Ming-Yuen

2018-02-02

Palythoa caribaeorum (class Anthozoa) is a zoanthid that together jellyfishes, hydra, and sea anemones, which are venomous and predatory, belongs to the Phyllum Cnidaria. The distinguished feature in these marine animals is the cnidocytes in the body tissues, responsible for toxin production and injection that are used majorly for prey capture and defense. With exception for other anthozoans, the toxin cocktails of zoanthids have been scarcely studied and are poorly known. Here, on the basis of the analysis of P. caribaeorum transcriptome, numerous predicted venom-featured polypeptides were identified including allergens, neurotoxins, membrane-active, and Kunitz-like peptides (PcKuz). The three predicted PcKuz isotoxins (1-3) were selected for functional studies. Through computational processing comprising structural phylogenetic analysis, molecular docking, and dynamics simulation, PcKuz3 was shown to be a potential voltage gated potassium-channel inhibitor. PcKuz3 fitted well as new functional Kunitz-type toxins with strong antilocomotor activity as in vivo assessed in zebrafish larvae, with weak inhibitory effect toward proteases, as evaluated in vitro. Notably, PcKuz3 can suppress, at low concentration, the 6-OHDA-induced neurotoxicity on the locomotive behavior of zebrafish, which indicated PcKuz3 may have a neuroprotective effect. Taken together, PcKuz3 figures as a novel neurotoxin structure, which differs from known homologous peptides expressed in sea anemone. Moreover, the novel PcKuz3 provides an insightful hint for biodrug development for prospective neurodegenerative disease treatment.

Pharmacological Potential of Phylogenetically Diverse Actinobacteria Isolated from Deep-Sea Coral Ecosystems of the Submarine Avilés Canyon in the Cantabrian Sea.

Science.gov (United States)

Sarmiento-Vizcaíno, Aida; González, Verónica; Braña, Alfredo F; Palacios, Juan J; Otero, Luis; Fernández, Jonathan; Molina, Axayacatl; Kulik, Andreas; Vázquez, Fernando; Acuña, José L; García, Luis A; Blanco, Gloria

2017-02-01

Marine Actinobacteria are emerging as an unexplored source for natural product discovery. Eighty-seven deep-sea coral reef invertebrates were collected during an oceanographic expedition at the submarine Avilés Canyon (Asturias, Spain) in a range of 1500 to 4700 m depth. From these, 18 cultivable bioactive Actinobacteria were isolated, mainly from corals, phylum Cnidaria, and some specimens of phyla Echinodermata, Porifera, Annelida, Arthropoda, Mollusca and Sipuncula. As determined by 16S rRNA sequencing and phylogenetic analyses, all isolates belong to the phylum Actinobacteria, mainly to the Streptomyces genus and also to Micromonospora, Pseudonocardia and Myceligenerans. Production of bioactive compounds of pharmacological interest was investigated by high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS) techniques and subsequent database comparison. Results reveal that deep-sea isolated Actinobacteria display a wide repertoire of secondary metabolite production with a high chemical diversity. Most identified products (both diffusible and volatiles) are known by their contrasted antibiotic or antitumor activities. Bioassays with ethyl acetate extracts from isolates displayed strong antibiotic activities against a panel of important resistant clinical pathogens, including Gram-positive and Gram-negative bacteria, as well as fungi, all of them isolated at two main hospitals (HUCA and Cabueñes) from the same geographical region. The identity of the active extracts components of these producing Actinobacteria is currently being investigated, given its potential for the discovery of pharmaceuticals and other products of biotechnological interest.

Hydroids (Cnidaria, Hydrozoa of the intertidal zone of Governador and Paquetá islands, Guanabara Bay, Rio de Janeiro, Brazil Hidróides (Cnidaria, Hydrozoa da zona entremarés das ilhas do Governador e Paquetá, Baía de Guanabara, Rio de Janeiro, Brasil

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Priscila A. Grohmann

2009-09-01

Full Text Available During six consecutive months, sampling were made at three points located on Governador Island and three on Paquetá Island in Guanabara Bay, Rio de Janeiro, Brazil. Material was collected from dock pilings and rocks in the intertidal zone. In these samples, five species belonging to three families, Corynidae, Kirchenpaueriidae and Campanulariidae, were identified. The campanulariid species Obelia dichotoma Linnaeus, 1758, dominated at nearly all points sampled. The small number of species obtained in this survey is attributed to the intense pollution in the bay, which borders the second-largest industrial complex and the second-largest demographic center of Brazil.Durante seis meses consecutivos foram feitas coletas em três pontos localizados na ilha do Governador e três em Paquetá, sendo colhido material em pilares de cais e rochas na zona entremarés. Foram identificadas cinco espécies pertencentes a três famílias: Corynidae, Kirchenpaueriidae e Campanulariidae. A espécie Obelia dichotoma Linnaeus, 1758 dominou em praticamente todos os pontos. O pequeno número de espécies encontradas neste levantamento deve-se, provavelmente, ao alto grau de poluição atualmente existente na baía, uma vez que ela abriga o segundo maior polo industrial e o segundo maior centro demográfico do Brasil.

Pachyseris inattesa sp. n. (Cnidaria, Anthozoa, Scleractinia): A new reef coral species from the red sea and its phylogenetic relationships

KAUST Repository

Terraneo, Tullia I.; Berumen, Michael L.; Arrigoni, Roberto; Waheed, Zarinah; Bouwmeester, Jessica; Caragnano, Annalisa; Stefani, Fabrizio; Benzoni, Francesca

2014-01-01

A new scleractinian coral species, Pachyseris inattesa sp. n., is described from the Red Sea. Despite a superficial resemblance with some species in the agariciid genus Leptoseris with which it has been previously confused, P. inattesa sp. n. has micro-morphological characters typical of the genus Pachyseris. This genus, once part of the Agariciidae, is comprised of five extant species and is widely distributed throughout the tropical Indo-Pacific. It is currently incertae sedis as a result of recent molecular analysis and appears to be closely related to the Euphylliidae. A molecular phylogenetic reconstruction including P. inattesa sp. n., the genus type species P. rugosa, and P. speciosa, all present in the Red Sea, was performed using the mitochondrial intergenic spacer between COI and 16S-rRNA. The results confirm that P. inattesa sp. n. is a monophyletic lineage closely related to the other Pachyseris species examined. © Tullia I. Terraneo et al.

Ontogeny reversal and phylogenetic analysis of Turritopsis sp.5 (Cnidaria, Hydrozoa, Oceaniidae, a possible new species endemic to Xiamen, China

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Jun-yuan Li

2018-01-01

Full Text Available Ontogeny reversal, as seen in some cnidarians, is an unprecedented phenomenon in the animal kingdom involving reversal of the ordinary life cycle. Three species of Turritopsis have been shown to be capable of inverted metamorphosis, a process in which the pelagic medusa transforms back into a juvenile benthic polyp stage when faced with adverse conditions. Turritopsis sp.5 is a species of Turritopsis collected from Xiamen, China which presents a similar ability, being able to reverse its life cycle if injured by mechanical stress. Phylogenetic analysis based on both 16S rDNA and cytochrome c oxidase subunit I (COI genetic barcodes shows that Turritopsis sp.5 is phylogenetically clustered in a clade separate from other species of Turritopsis. The genetic distance between T. sp.5 and the Japanese species T. sp.2 is the shortest, when measured by the Kimura 2-Parameter metric, and the distance to the New Zealand species T. rubra is the largest. An experimental assay on the induction of reverse development in this species was initiated by cutting medusae into upper and lower parts. We show, for the first time, that the two dissected parts have significantly different potentials to transform into polyps. Also, a series of morphological changes of the reversed life cycle can be recognised, including medusa stage, contraction stage I, contraction stage II, cyst, cyst with stolons, and polyp. The discovery of species capable of reverse ontogeny caused by unfavorable conditions adds to the available systems with which to study the cell types that contribute to the developmental reversal and the molecular mechanisms of the directional determination of ontogeny.

Fouling community dominated by Metridium senile (Cnidaria: Anthozoa: Actiniaria in Bahía San Julián (southern Patagonia, Argentina

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Juan Pablo Martin

2015-06-01

Full Text Available The objective of this study is to provide information about a harbour-fouling community dominated by Metridium senile in southern Patagonia. Several steel tubes from the wharf of Puerto San Julián were extracted to perform repair tasks, allowing the attached benthic community to be studied. Sampling was conducted at three levels: lower intertidal, 3-4 m depth and 6-7 m depth. In the lower intertidal, M. senile had a relative abundance of 43%, the most abundant accompanying species being Perumytilus purpuratus, Mytilus edulis platensis and Aulacomya atra atra. At subtidal level, the anemone showed relative abundances of 64% and 65%, and was accompanied by Monocorophium insidiosum at 3-4 m depth and by polychaetes of families Sabellidae and Syllidae at 6-7 m at depth. In the lower intertidal, epibiosis was more frequent on P. purpuratus, A. atra atra and M. edulis platensis, while in the subtidal, the richness of substrate-organisms increased significantly and the anemone was fixed to A. atra atra, M. edulis platensis, Paramolgula gregaria, Crepipatella dilatata, Austromegabalanus psittacus, Hiatella arctica, Polyzoa opuntia, Pyura sp. and Sabellidae tubes. The ability of M. senile to settle on many different organisms, along with other strategies, makes it a colonizer able to displace other species that could compete with it for substratum. Given the cosmopolitan nature of M. senile, the fact that this species has not been previously reported in the coastal zone of the region, and the results of our study, we discuss the possibility that this sea anemone is an invasive alien species in southern Patagonia, or at least a cryptogenic species.

Possible natural hybridization of two morphologically distinct species of Acropora (Cnidaria, Scleractinia in the Pacific: fertilization and larval survival rates.

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Naoko Isomura

Full Text Available Natural hybridization of corals in the Indo-Pacific has been considered rather rare. However, field studies have observed many corals with intermediate interspecific or unusual morphologies. Given that the existence of F1 hybrids with intermediate interspecific morphologies has been proven in the Caribbean, hybrids may also inhabit the Indo-Pacific and occur more frequently than expected. In this study, we focused on two morphologically different species, Acropora florida and A. intermedia, and performed crossing experiments at Akajima Island, Japan. Results showed that these species could hybridize in both directions via eggs and sperm, but that fertilization rates significantly differed according to which species provided eggs. These results are similar to those reported from the Caribbean. Although all embryos developed normally to the planular larval stage, the developmental processes of some hybrid embryos were delayed by approximately 1 h compared with conspecific embryos, suggesting that fertilization occurred 1 h later in interspecific crosses than in intraspecific crosses. More successful hybridization could occur under conditions with low numbers of conspecific colonies. Additionally, a comparison of survival rates between hybrid and intraspecific larvae revealed that intra- and interspecific larvae produced from eggs of A. florida survived for significantly longer than those produced from eggs of A. intermedia. Considering these data, under specific conditions, hybrids can be expected to be produced and survive in nature in the Pacific. Furthermore, we identified one colony with intermediate morphology between A. florida and A. intermedia in the field. This colony was fertilized only by eggs of A. florida, with high fertilization rates, suggesting that this colony would be a hybrid of these two species and might be backcrossed.

Morphological and molecular characterization of a novel myxosporean parasite Myxobolus bejeranoi n. sp. (Cnidaria: Myxosporea) from hybrid tilapia in Israel.

Science.gov (United States)

Lövy, Alena; Smirnov, Margarita; Brekhman, Vera; Ofek, Tamir; Lotan, Tamar

2018-02-01

Myxosporean infections can cause severe damage to commercially grown tilapia. Here, we report a novel myxosporean that was found in gills of Oreochromis aureus male × Oreochromis niloticus female, which is an important aquaculture tilapia hybrid in Israel. Three-month-old fish were found to have cysts located in gill muscle tissue, which were filled with both immature and mature spores. Affected fish displayed higher mortality rate. Spore dimensions (10.8 ± 0.7 μm length × 6.8 ± 0.6 μm width) and molecular characterization using 18S ribosomal DNA revealed that the unknown parasite belongs in the Myxobolus clade. Based on the infection site, spore morphology and molecular characterization, we describe this parasite as Myxobolus bejeranoi n. sp. (MF401455). Phylogenetic analysis showed that the new species is most closely related to two Myxobolus spp. from O. niloticus in Egypt and Ghana.

Ocurrence of the sea anemone Telmatactis panamensis (Verrill, 1869 (Cnidaria: Anthozoa: Actiniaria at Isla del Coco National Park, Costa Rica

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Fabián H. Acuña

2012-11-01

Full Text Available The sea anemone fauna of Isla del Coco National Park (also known as Cocos Island Nacional Park, Pacific Costa Rica is poorly known. In the present work we report the first occurrence of the species Telmatactis panamensis. Individuals of this sea anemone (n=24 were collected at Chatham Bay intertidal and at 15m depth in Punta Ulloa, in both cases attached to rocks; during the expedition UCR-UNA-COCO-I in April 2010. We provide photographs of live individuals, external anatomy and an inventory of cnidae of the studied specimens. Possibly this species is extended to greater depth as observed by other authors in the Galápagos Islands.La fauna de anémonas de mar es prácticamente desconocida para el Parque Nacional Isla del Coco (Costa Rica. En el presente trabajo se reporta por primera vez la presencia de la especie Telmatactis panamensis. Individuos de esta anémona de mar fueron colectados en el intermareal de Bahía Chatham y a 15m de profundidad en Punta Ulloa, en ambos casos adheridas a rocas; durante la expedición UCR-UNA-COCO-I en Abril de 2010. Se proveen fotografías de ejemplares vivos, datos de su anatomía externa y un inventario del cnidae de los especímenes estudiados. Posiblemente esta especie se extienda a mayor profundidad, tal como fue observado por otros autores para ejemplares de las Islas Galápagos.

Pachyseris inattesa sp. n. (Cnidaria, Anthozoa, Scleractinia): A new reef coral species from the red sea and its phylogenetic relationships

KAUST Repository

Terraneo, Tullia I.

2014-08-13

A new scleractinian coral species, Pachyseris inattesa sp. n., is described from the Red Sea. Despite a superficial resemblance with some species in the agariciid genus Leptoseris with which it has been previously confused, P. inattesa sp. n. has micro-morphological characters typical of the genus Pachyseris. This genus, once part of the Agariciidae, is comprised of five extant species and is widely distributed throughout the tropical Indo-Pacific. It is currently incertae sedis as a result of recent molecular analysis and appears to be closely related to the Euphylliidae. A molecular phylogenetic reconstruction including P. inattesa sp. n., the genus type species P. rugosa, and P. speciosa, all present in the Red Sea, was performed using the mitochondrial intergenic spacer between COI and 16S-rRNA. The results confirm that P. inattesa sp. n. is a monophyletic lineage closely related to the other Pachyseris species examined. © Tullia I. Terraneo et al.

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.

Crude venom from nematocysts of Pelagia noctiluca (Cnidaria: Scyphozoa) elicits a sodium conductance in the plasma membrane of mammalian cells

Science.gov (United States)

Morabito, Rossana; Costa, Roberta; Rizzo, Valentina; Remigante, Alessia; Nofziger, Charity; La Spada, Giuseppa; Marino, Angela; Paulmichl, Markus; Dossena, Silvia

2017-01-01

Cnidarians may negatively impact human activities and public health but concomitantly their venom represents a rich source of bioactive substances. Pelagia noctiluca is the most venomous and abundant jellyfish of the Mediterranean Sea and possesses a venom with hemolytic and cytolytic activity for which the mechanism is largely unknown. Here we show that exposure of mammalian cells to crude venom from the nematocysts of P. noctiluca profoundly alters the ion conductance of the plasma membrane, therefore affecting homeostatic functions such as the regulation and maintenance of cellular volume. Venom-treated cells exhibited a large, inwardly rectifying current mainly due to permeation of Na+ and Cl-, sensitive to amiloride and completely abrogated following harsh thermal treatment of crude venom extract. Curiously, the plasma membrane conductance of Ca2+ and K+ was not affected. Current-inducing activity was also observed following delivery of venom to the cytosolic side of the plasma membrane, consistent with a pore-forming mechanism. Venom-induced NaCl influx followed by water and consequent cell swelling most likely underlie the hemolytic and cytolytic activity of P. noctiluca venom. The present study underscores unique properties of P. noctiluca venom and provides essential information for a possible use of its active compounds and treatment of envenomation.

Investigating Species Boundaries within the Hard Coral Genus Goniopora (Cnidaria, Scleractinia) from the Red Sea Using an Integrative Morphomolecular Approach

KAUST Repository

Terraneo, Tullia Isotta

2015-12-01

In the present study the species boundaries of the scleractinian coral genus Goniopora from the Saudi Arabian Red Sea were investigated. An integrated morpho-molecular approach was used to better clarify the complex scenario derived from traditional classification efforts based on skeletal morphology. Traditional taxonomy of this genus considers skeletal morphology first and polyp morphology as a secondary discriminating character. This leads to potential complication due to plasticity in skeletal features within a species. To address this issue, molecular analyses of evolutionary relationships between nine traditional morphospecies of Goniopora from the Red Sea were performed and were used to re-evaluate the informativeness of macromorphological and micromorphological features. Between four and six putative molecular lineages were identified within Goniopora samples from the Saudi Arabian Red Sea on the basis of four molecular markers: the mitochondrial intergenic spacer between Cytochrome b and the NADH dehydrogenase subunit 2, the entire nuclear ribosomal internal transcribed spacer region, the ATP synthase subunit β gene, and a portion of the Calmodulin gene. The results were strongly corroborated by three distinct analyses of species delimitation. Subsequent analyses of micromorphological and microstructural skeletal features identified the presence of distinctive characters in each of the molecular clades. Unique in vivo morphologies were associated with the genetic-delimited lineages, further supporting the molecular findings. The proposed re-organization of Goniopora will resolve several taxonomic problems in this genus while reconciling molecular and morphological evidence. Reliable species-level identification of Goniopora spp. can be achieved with polyp morphology under the proposed revision.

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.

Macro- and megafauna recorded in the submarine Bari Canyon (southern Adriatic, Mediterranean Sea using different tools

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G. D'ONGHIA

2015-01-01

Full Text Available Macro- and megafauna were recorded in the submarine Bari Canyon (southern Adriatic Sea, Mediterranean Sea during an oceanographic cruise carried out in May-June 2012 and an experimental fishing survey conducted in November 2013. During the former, a total of 20 benthic samples were taken using a Van Veen grab at depths between 268 and 770 m and 4 deployments of a baited lander, for about 43 hours of video records, were carried out at depths between 443 and 788 m. During the latter, 8 longline fishing operations were conducted from 338 down to 612 m. Eighty-five living benthic and benthopelagic species were recorded: 29 Porifera, 1 Cnidaria, 2 Mollusca, 11 Annelida, 1 Arthropoda, 19 Bryozoa, 3 Echinodermata and 19 Chordata. A total of 51 species are new records for the Bari Canyon, 29 new records for the Adriatic Sea. Among the Porifera Cerbaris curvispiculifer is a new addition for the Italian Sponge Fauna. The first certain record of living specimens for the bryozoan Crisia tenella longinodata is reported. A total of 6 Mediterranean endemic species have been identified: 4 Porifera and 2 Annelida. The bathymetric range of some species has been extended. New information acquired for deep sea species confirms their importance in the structure of cold-water coral communities. This study has updated the knowledge on the biodiversity of the Adriatic Sea, as well as of the Bari Canyon in particular, one of the sites designated as “jewels of the Mediterranean” for which urgent conservation measures are needed.

Evolutionary transitions in symbioses: dramatic reductions in bathymetric and geographic ranges of Zoanthidea coincide with loss of symbioses with invertebrates.

Science.gov (United States)

Swain, Timothy D

2010-06-01

Two fundamental symbiosis-based trophic types are recognized among Zoanthidea (Cnidaria, Anthozoa): fixed carbon is either obtained directly from zooxanthellae photosymbionts or from environmental sources through feeding with the assistance of host-invertebrate behaviour and structure. Each trophic type is characteristic of the suborders of Zoanthidea and is associated with substantial distributional asymmetries: suborder Macrocnemina are symbionts of invertebrates and have global geographic and bathymetric distributions and suborder Brachycnemina are hosts of endosymbiotic zooxanthellae and are restricted to tropical photic zones. While exposure to solar radiation could explain the bathymetric asymmetry it does not explain the geographic asymmetry, nor is it clear why evolutionary transitions to the zooxanthellae-free state have apparently occurred within Macrocnemina but not within Brachycnemina. To better understand the transitions between symbiosis-based trophic types of Zoanthidea, a concatenated data set of nuclear and mitochondrial nucleotide sequences were used to test hypotheses of monophyly for groups defined by morphology and symbiosis, and to reconstruct the evolutionary transitions of morphological and symbiotic characters. The results indicate that the morphological characters that define Macrocnemina are plesiomorphic and the characters that define its subordinate taxa are homoplasious. Symbioses with invertebrates have ancient and recent transitions with a general pattern of stability in host associations through evolutionary time. The reduction in distribution of Zoanthidea is independent of the evolution of zooxanthellae symbiosis and consistent with hypotheses of the benefits of invertebrate symbioses, indicating that the ability to persist in most habitats may have been lost with the termination of symbioses with invertebrates.

Indoles induce metamorphosis in a broad diversity of jellyfish, but not in a crown jelly (Coronatae).

Science.gov (United States)

Helm, Rebecca R; Dunn, Casey W

2017-01-01

Many animals go through one or more metamorphoses during their lives, however, the molecular underpinnings of metamorphosis across diverse species are not well understood. Medusozoa (Cnidaria) is a clade of animals with complex life cycles, these life cycles can include a polyp stage that metamorphoses into a medusa (jellyfish). Medusae are produced through a variety of different developmental mechanisms-in some species polyps bud medusae (Hydrozoa), in others medusae are formed through polyp fission (Scyphozoa), while in others medusae are formed through direct transformation of the polyp (Cubozoa). To better understand the molecular mechanisms that may coordinate these different forms of metamorphosis, we tested two compounds first identified to induce metamorphosis in the moon jellyfish Aurelia aurita (indomethacin and 5-methoxy-2-methylindole) on a broad diversity of medusozoan polyps. We discovered that indole-containing compounds trigger metamorphosis across a broad diversity of species. All tested discomedusan polyps metamorphosed in the presence of both compounds, including species representatives of several major lineages within the clade (Pelagiidae, Cyaneidae, both clades of Rhizostomeae). In a cubozoan, low levels of 5-methoxy-2-methylindole reliably induced complete and healthy metamorphosis. In contrast, neither compound induced medusa metamorphosis in a coronate scyphozoan, or medusa production in either hydrozoan tested. Our results support the hypothesis that metamorphosis is mediated by a conserved induction pathway within discomedusan scyphozoans, and possibly cubozoans. However, failure of these compounds to induce metamorphosis in a coronate suggests this induction mechanism may have been lost in this clade, or is convergent between Scyphozoa and Cubozoa.

Three Cambrian fossils assembled into an extinct body plan of cnidarian affinity.

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Ou, Qiang; Han, Jian; Zhang, Zhifei; Shu, Degan; Sun, Ge; Mayer, Georg

2017-08-15

The early Cambrian problematica Xianguangia sinica , Chengjiangopenna wangii , and Galeaplumosus abilus from the Chengjiang biota (Yunnan, China) have caused much controversy in the past and their phylogenetic placements remain unresolved. Here we show, based on exceptionally preserved material (85 new specimens plus type material), that specimens previously assigned to these three species are in fact parts of the same organism and propose that C. wangii and G. abilus are junior synonyms of X. sinica Our reconstruction of the complete animal reveals an extinct body plan that combines the characteristics of the three described species and is distinct from all known fossil and living taxa. This animal resembled a cnidarian polyp in overall morphology and having a gastric cavity partitioned by septum-like structures. However, it possessed an additional body cavity within its holdfast, an anchoring pit on the basal disk, and feather-like tentacles with densely ciliated pinnules arranged in an alternating pattern, indicating that it was a suspension feeder rather than a predatory actiniarian. Phylogenetic analyses using Bayesian inference and maximum parsimony suggest that X. sinica is a stem-group cnidarian. This relationship implies that the last common ancestor of X. sinica and crown cnidarians was probably a benthic, polypoid animal with a partitioned gastric cavity and a single mouth/anus opening. This extinct body plan suggests that feeding strategies of stem cnidarians may have been drastically different from that of their crown relatives, which are almost exclusively predators, and reveals that the morphological disparity of total-group Cnidaria is greater than previously assumed.

Morphology and phylogeny of two new species of Sphaeromyxa Thélohan, 1892 (Cnidaria: Myxozoa) from marine fish (Clinidae and Trachichthyidae)

Czech Academy of Sciences Publication Activity Database

Bartošová-Sojková, Pavla; Kodádková, Alena; Pecková, Hana; Kuchta, Roman; Reed, C. C.

2015-01-01

Roč. 142, č. 5 (2015), s. 660-674 ISSN 0031-1820 R&D Projects: GA ČR GBP505/12/G112 Institutional support: RVO:60077344 Keywords : Myxosporea * Clinidae * Gephyroberyx * ultrastructure * evolution * Sphaeromyxa clade * SSU rDNA * new species Subject RIV: EG - Zoology Impact factor: 3.031, year: 2015

Lectotype designations of new species of hydroids (Cnidaria, Hydrozoa), described by C.M. Fraser, from Allan Hancock Pacific and Caribbean Sea Expeditions

NARCIS (Netherlands)

Calder, D.R.; Vervoort, W.; Hochberg, F.G.

2009-01-01

Hydroids of the Allan Hancock Pacific Expeditions, and those of the Allan Hancock Caribbean Sea Expedition, were examined by Charles McLean Fraser in a series of reports published between 1938 and 1948. A total of 159 new nominal species was described from material collected in the eastern Pacific

Observations on the symbiosis between Colus gracilis (Da Costa, 1778) (Mollusca: Gastropoda) and Hormathia digitata (O.F. Müller, 1776) (Cnidaria: Actiniaria)

NARCIS (Netherlands)

Ates, R.M.L.

1998-01-01

Aquarium observations of the behaviour of the actinian Hormathia digitata when mounting live specimens of the gastropod Colus gracilis are fully described for the first time. C. gracilis actively initiates an association with H. digitata by approaching and remaining stationary near the actinian.

Gene Expression Data from the Moon Jelly, Aurelia, Provide Insights into the Evolution of the Combinatorial Code Controlling Animal Sense Organ Development.

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Nagayasu Nakanishi

Full Text Available In Bilateria, Pax6, Six, Eya and Dach families of transcription factors underlie the development and evolution of morphologically and phyletically distinct eyes, including the compound eyes in Drosophila and the camera-type eyes in vertebrates, indicating that bilaterian eyes evolved under the strong influence of ancestral developmental gene regulation. However the conservation in eye developmental genetics deeper in the Eumetazoa, and the origin of the conserved gene regulatory apparatus controlling eye development remain unclear due to limited comparative developmental data from Cnidaria. Here we show in the eye-bearing scyphozoan cnidarian Aurelia that the ectodermal photosensory domain of the developing medusa sensory structure known as the rhopalium expresses sine oculis (so/six1/2 and eyes absent/eya, but not optix/six3/6 or pax (A&B. In addition, the so and eya co-expression domain encompasses the region of active cell proliferation, neurogenesis, and mechanoreceptor development in rhopalia. Consistent with the role of so and eya in rhopalial development, developmental transcriptome data across Aurelia life cycle stages show upregulation of so and eya, but not optix or pax (A&B, during medusa formation. Moreover, pax6 and dach are absent in the Aurelia genome, and thus are not required for eye development in Aurelia. Our data are consistent with so and eya, but not optix, pax or dach, having conserved functions in sensory structure specification across Eumetazoa. The lability of developmental components including Pax genes relative to so-eya is consistent with a model of sense organ development and evolution that involved the lineage specific modification of a combinatorial code that specifies animal sense organs.

Marine Invertebrate Larvae Associated with Symbiodinium: A Mutualism from the Start?

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Miguel Mies

2017-05-01

Full Text Available Symbiodinium are dinoflagellate photosynthetic algae that associate with a diverse array of marine invertebrates, and these relationships are comprehensively documented for adult animal hosts. Conversely, comparatively little is known about the associations during larval development of animal hosts, although four different metazoan phyla (Porifera, Cnidaria, Acoelomorpha, and Mollusca produce larvae associated with Symbiodinium. These phyla represent considerable diversities in larval forms, manner of symbiont acquisition, and requirements on the presence of symbionts for successful metamorphosis. Importantly, the different requirements are conveyed by specific symbiont types that are selected by the host animal larvae. Nevertheless, it remains to be determined whether these associations during larval stages already represent mutualistic interactions, as evident from the relationship of Symbiodinium with their adult animal hosts. For instance, molecular studies suggest that the host larval transcriptome is nearly unaltered after symbiont acquisition. Even so, a symbiosis-specific gene has been identified in Symbiodinium that is expressed in larval host stages, and similar genes are currently being described for host organisms. However, some reports suggest that the metabolic exchange between host larvae and Symbiodinium may not cover the energetic requirements of the host. Here, we review current studies to summarize what is known about the association between metazoan larvae and Symbiodinium. In particular, our aim was to gather in how far the mutualistic relationship present between adult animals hosts and Symbiodinium is already laid out at the time of symbiont acquisition by host larvae. We conclude that the mutualistic relationship between animal hosts and algal symbionts in many cases is not set up during larval development. Furthermore, symbiont identity may influence whether a mutualism can be established during host larval stages.

Transdermal delivery of scopolamine by natural submicron injectors: in-vivo study in pig.

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Esther Shaoul

Full Text Available Transdermal drug delivery has made a notable contribution to medical practice, but has yet to fully achieve its potential as an alternative to oral delivery and hypodermic injections. While transdermal delivery systems would appear to provide an attractive solution for local and systemic drug delivery, only a limited number of drugs can be delivered through the outer layer of the skin. The most difficult to deliver in this way are hydrophilic drugs. The aquatic phylum Cnidaria, which includes sea anemones, corals, jellyfish and hydra, is one of the most ancient multicellular phyla that possess stinging cells containing organelles (cnidocysts, comprising a sophisticated injection system. The apparatus is folded within collagenous microcapsules and upon activation injects a thin tubule that immediately penetrates the prey and delivers its contents. Here we show that this natural microscopic injection system can be adapted for systemic transdermal drug delivery once it is isolated from the cells and uploaded with the drug. Using a topically applied gel containing isolated natural sea anemone injectors and the muscarinic receptor antagonist scopolamine, we found that the formulated injectors could penetrate porcine skin and immediately deliver this hydrophilic drug. An in-vivo study in pigs demonstrated, for the first time, rapid systemic delivery of scopolamine, with T(max of 30 minutes and C(max 5 times higher than in controls treated topically with a scopolamine-containing gel without cnidocysts. The ability of the formulated natural injection system to penetrate a barrier as thick as the skin and systemically deliver an exogenous compound presents an intriguing and attractive alternative for hydrophilic transdermal drug delivery.

Marine Invertebrate Larvae Associated with Symbiodinium: A Mutualism from the Start?

KAUST Repository

Mies, Miguel

2017-05-30

Symbiodinium are dinoflagellate photosynthetic algae that associate with a diverse array of marine invertebrates, and these relationships are comprehensively documented for adult animal hosts. Conversely, comparatively little is known about the associations during larval development of animal hosts, although four different metazoan phyla (Porifera, Cnidaria, Acoelomorpha, and Mollusca) produce larvae associated with Symbiodinium. These phyla represent considerable diversities in larval forms, manner of symbiont acquisition, and requirements on the presence of symbionts for successful metamorphosis. Importantly, the different requirements are conveyed by specific symbiont types that are selected by the host animal larvae. Nevertheless, it remains to be determined whether these associations during larval stages already represent mutualistic interactions, as evident from the relationship of Symbiodinium with their adult animal hosts. For instance, molecular studies suggest that the host larval transcriptome is nearly unaltered after symbiont acquisition. Even so, a symbiosis-specific gene has been identified in Symbiodinium that is expressed in larval host stages, and similar genes are currently being described for host organisms. However, some reports suggest that the metabolic exchange between host larvae and Symbiodinium may not cover the energetic requirements of the host. Here, we review current studies to summarize what is known about the association between metazoan larvae and Symbiodinium. In particular, our aim was to gather in how far the mutualistic relationship present between adult animals hosts and Symbiodinium is already laid out at the time of symbiont acquisition by host larvae. We conclude that the mutualistic relationship between animal hosts and algal symbionts in many cases is not set up during larval development. Furthermore, symbiont identity may influence whether a mutualism can be established during host larval stages.

Isotopic variations ({delta}{sup 13} C and {delta}{sup 18} O) in Siderastrea stellata (Cnidaria-Anthozoa), Itamaraca island, State of Pernambuco, Northeastern Brazil

Energy Technology Data Exchange (ETDEWEB)

Ferreira, Valderez P.; Sial, Alcides N. [Pernambuco Univ., Recife, PE (Brazil). Dept. de Geologia. Lab. de Isotopos Estaveis; Mayeal, Elga M.; Exner, Marco Antonio [Pernambuco Univ., Recife, PE (Brazil). Dept. de Zoologia. Lab. de Macro e Megabentos

1998-12-01

Isotopic determinations for O and C were performed in coral skeletons collected in beach rocks from two localities (Orange and Catuama), Itamaraca Island, north littoral of the State of pernambuco, northeastern Brazil. Large variations of {delta}{sup 18} O and {delta}{sup 13} C in corals from both localities are found, the largest ones being observed at the Orange locality {delta}{sup 13} C in this locality varies from -0.8 to +1.8% PDB and {delta}{sup 1.8} O from -5.3 to -1.8% PDB, while at the Catuama locality, they vary from -1.8 to 0.1% PDB and -3.8 to -2.7% PDB, respectively. Large variations in {delta}{sup 18} O (up to 2.5%) coupled with weakly defined positive correlation between {delta}{sup 18} O and {delta}{sup 13} C, can be attributed to temperature variations as consequence of climatic perturbations. Temperature estimates, calculated from {delta}{sup 18} O values, assuming isotopic equilibrium with seawater, yield values between 24.9 deg C and 43.1 deg C at Orange, and from 28.4 deg C to 35 deg C at Catuama, all of them (expect one growth band from one sample) are high enough for the full development of the coral colony. Temperature average is 31.4 deg C at Orange, which is a little bit higher than that at Catuama, but both of them indicate thermal stress conditions. In all analyzed specimens, expect for one, at Orange, T increases was accompanied by decreasing in the organic activity, as suggested by corresponding negative {delta}{sup 13} C anomaly. Therefore, the observed bleaching is possibly related to thermal stress and the high T may be related to the El Nino-Southern Oscillation (ENSO) warning event. On the other hand, anthropogenic action at Orange, local of intense tourism throughout the year, coupled with high rate of sedimentation in the region, may contribute to the observed coral bleaching. (author)

Susceptibility to antibiotics of Vibrio sp. AO1 growing in pure culture or in association with its hydroid host Aglaophenia octodonta (Cnidaria, Hydrozoa).

Science.gov (United States)

Stabili, Loredana; Gravili, Cinzia; Boero, Ferdinando; Tredici, Salvatore M; Alifano, Pietro

2010-04-01

Vibrio harveyi is the major causal organism of vibriosis, causing potential devastation to diverse ranges of marine invertebrates over a wide geographical area. These microorganisms, however, are phenotypically diverse, and many of the isolates are also resistant to multiple antibiotics. In a previous study, we described a previously unknown association between Vibrio sp. AO1, a luminous bacterium related to the species V. harveyi, and the benthic hydrozoan Aglaophenia octodonta. In this study, we analyzed the susceptibility to antibiotics (ampicillin, streptomycin, tetracycline, or co-trimoxazole = mix of sulfamethoxazole and trimetoprim) of Vibrio sp. AO1 growing in pure culture or in association with its hydroid host by using microcosm experiments. The results of minimum inhibitory concentration (MIC) experiments demonstrated that Vibrio sp. AO1 was highly resistant to ampicillin and streptomycin in pure culture. Nevertheless, these antibiotics, when used at sub-MIC values, significantly reduced the hydroid fluorescence. Co-trimoxazole showed the highest inhibitory effect on fluorescence of A. octodonta. However, in all treatments, the fluorescence was reduced after 48 h, but never disappeared completely around the folds along the hydrocaulus and at the base of the hydrothecae of A. octodonta when the antibiotic was used at concentration completely inhibiting growth in vitro. The apparent discrepancy between the MIC data and the fluorescence patterns may be due to either heterogeneity of the bacterial population in terms of antibiotic susceptibility or specific chemical-physical conditions of the hydroid microenvironment that may decrease the antibiotic susceptibility of the whole population. The latter hypothesis is supported by scanning electron microscope evidence for development of bacterial biofilm on the hydroid surface. On the basis of the results obtained, we infer that A. octodonta might behave as a reservoir of antibiotic multiresistant bacteria, increasing the risk of their transfer into aquaculture farms.

"Candidatus Fokinia solitaria", a Novel "Stand-Alone" Symbiotic Lineage of Midichloriaceae (Rickettsiales.

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Franziska Szokoli

Full Text Available Recently, the family Midichloriaceae has been described within the bacterial order Rickettsiales. It includes a variety of bacterial endosymbionts detected in different metazoan host species belonging to Placozoa, Cnidaria, Arthropoda and Vertebrata. Representatives of Midichloriaceae are also considered possible etiological agents of certain animal diseases. Midichloriaceae have been found also in protists like ciliates and amoebae. The present work describes a new bacterial endosymbiont, "Candidatus Fokinia solitaria", retrieved from three different strains of a novel Paramecium species isolated from a wastewater treatment plant in Rio de Janeiro (Brazil. Symbionts were characterized through the full-cycle rRNA approach: SSU rRNA gene sequencing and fluorescence in situ hybridization (FISH with three species-specific oligonucleotide probes. In electron micrographs, the tiny rod-shaped endosymbionts (1.2 x 0.25-0.35 μm in size were not surrounded by a symbiontophorous vacuole and were located in the peripheral host cytoplasm, stratified in the host cortex in between the trichocysts or just below them. Frequently, they occurred inside autolysosomes. Phylogenetic analyses of Midichloriaceae apparently show different evolutionary pathways within the family. Some genera, such as "Ca. Midichloria" and "Ca. Lariskella", have been retrieved frequently and independently in different hosts and environmental surveys. On the contrary, others, such as Lyticum, "Ca. Anadelfobacter", "Ca. Defluviella" and the presently described "Ca. Fokinia solitaria", have been found only occasionally and associated to specific host species. These last are the only representatives in their own branches thus far. Present data do not allow to infer whether these genera, which we named "stand-alone lineages", are an indication of poorly sampled organisms, thus underrepresented in GenBank, or represent fast evolving, highly adapted evolutionary lineages.

Gene expression profiles during short-term heat stress; branching vs. massive Scleractinian corals of the Red Sea

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Keren Maor-Landaw

2016-03-01

Full Text Available It is well-established that there is a hierarchy of susceptibilities amongst coral genera during heat-stress. However, molecular mechanisms governing these differences are still poorly understood. Here we explored if specific corals possessing different morphologies and different susceptibilities to heat stress may manifest varied gene expression patterns. We examined expression patterns of seven genes in the branching corals Stylophora pistillata and Acropora eurystoma and additionally in the massive robust coral, Porites sp. The tested genes are representatives of key cellular processes occurring during heat-stress in Cnidaria: oxidative stress, ER stress, energy metabolism, DNA repair and apoptosis. Varied response to the heat-stress, in terms of visual coral paling, algal maximum quantum yield and host gene expression was evident in the different growth forms. The two branching corals exhibited similar overall responses that differed from that of the massive coral. A. eurystoma that is considered as a susceptible species did not bleach in our experiment, but tissue sloughing was evident at 34 °C. Interestingly, in this species redox regulation genes were up-regulated at the very onset of the thermal challenge. In S. pistillata, bleaching was evident at 34 °C and most of the stress markers were already up-regulated at 32 °C, either remaining highly expressed or decreasing when temperatures reached 34 °C. The massive Porites species displayed severe bleaching at 32 °C but stress marker genes were only significantly elevated at 34 °C. We postulate that by expelling the algal symbionts from Porites tissues, oxidation damages are reduced and stress genes are activated only at a progressed stage. The differential gene expression responses exhibited here can be correlated with the literature well-documented hierarchy of susceptibilities amongst coral morphologies and genera in Eilat’s coral reef.

Regulation of intracellular pH in cnidarians: response to acidosis in Anemonia viridis.

Science.gov (United States)

Laurent, Julien; Venn, Alexander; Tambutté, Éric; Ganot, Philippe; Allemand, Denis; Tambutté, Sylvie

2014-02-01

The regulation of intracellular pH (pHi) is a fundamental aspect of cell physiology that has received little attention in studies of the phylum Cnidaria, which includes ecologically important sea anemones and reef-building corals. Like all organisms, cnidarians must maintain pH homeostasis to counterbalance reductions in pHi, which can arise because of changes in either intrinsic or extrinsic parameters. Corals and sea anemones face natural daily changes in internal fluids, where the extracellular pH can range from 8.9 during the day to 7.4 at night. Furthermore, cnidarians are likely to experience future CO₂-driven declines in seawater pH, a process known as ocean acidification. Here, we carried out the first mechanistic investigation to determine how cnidarian pHi regulation responds to decreases in extracellular and intracellular pH. Using the anemone Anemonia viridis, we employed confocal live cell imaging and a pH-sensitive dye to track the dynamics of pHi after intracellular acidosis induced by acute exposure to decreases in seawater pH and NH₄Cl prepulses. The investigation was conducted on cells that contained intracellular symbiotic algae (Symbiodinium sp.) and on symbiont-free endoderm cells. Experiments using inhibitors and Na⁺-free seawater indicate a potential role of Na⁺/H⁺ plasma membrane exchangers (NHEs) in mediating pHi recovery following intracellular acidosis in both cell types. We also measured the buffering capacity of cells, and obtained values between 20.8 and 43.8 mM per pH unit, which are comparable to those in other invertebrates. Our findings provide the first steps towards a better understanding of acid-base regulation in these basal metazoans, for which information on cell physiology is extremely limited. © 2013 FEBS.

Life in a rock pool: Radiation and population genetics of myxozoan parasites in hosts inhabiting restricted spaces.

Science.gov (United States)

Bartošová-Sojková, Pavla; Lövy, Alena; Reed, Cecile C; Lisnerová, Martina; Tomková, Tereza; Holzer, Astrid S; Fiala, Ivan

2018-01-01

Intertidal rock pools where fish and invertebrates are in constant close contact due to limited space and water level fluctuations represent ideal conditions to promote life cycles in parasites using these two alternate hosts and to study speciation processes that could contribute to understanding the roles of parasitic species in such ecosystems. Gall bladder and liver samples from five clinid fish species (Blenniiformes: Clinidae) were morphologically and molecularly examined to determine the diversity, prevalence, distribution and host specificity of Ceratomyxa parasites (Cnidaria: Myxozoa) in intertidal habitats along the coast of South Africa. Phylogenetic relationships of clinid ceratomyxids based on the SSU rDNA, LSU rDNA and ITS regions were assessed additionally to the investigation of population genetic structure of Ceratomyxa cottoidii and subsequent comparison with the data known from type fish host Clinus cottoides. Seven Ceratomyxa species including previously described Ceratomyxa dehoopi and C. cottoidii were recognized in clinids. They represent a diverse group of rapidly evolving, closely related species with a remarkably high prevalence in their hosts, little host specificity and frequent concurrent infections, most probably as a result of parasite radiation after multiple speciation events triggered by limited host dispersal within restricted spaces. C. cottoidii represents the most common clinid parasite with a population structure characterized by young expanding populations in the south west and south east coast and by older populations in equilibrium on the west coast of its distribution. Parasite and fish host population structures show overlapping patterns and are very likely affected by similar oceanographic barriers possibly due to reduced host dispersal enhancing parasite community differentiation. While fish host specificity had little impact on parasite population structure, the habitat preference of the alternate invertebrate host as

Evidence for participation of GCS1 in fertilization of the starlet sea anemone Nematostella vectensis: Implication of a common mechanism of sperm–egg fusion in plants and animals

Energy Technology Data Exchange (ETDEWEB)

Ebchuqin, Eerdundagula; Yokota, Naoto; Yamada, Lixy [Sugashima Marine Biological Laboratory, Graduate School of Science, Nagoya University, Sugashima, Toba 517-0004 (Japan); Yasuoka, Yuuri [Marine Genomics Unit, Okinawa Institute of Science and Technology, Onna, Okinawa 904-0495 (Japan); Akasaka, Mari [Laboratory of Molecular Genetics, Graduate School of Science, Nagoya University, Chikusa-ku, Furo-cho, Nagoya 464-8602 (Japan); Arakawa, Mio; Deguchi, Ryusaku [Department of Biology, Miyagi University of Education, Sendai, Miyagi 980-0845 (Japan); Mori, Toshiyuki [Waseda Institute for Advanced Study, Waseda University, Shinjuku, Tokyo 169-8050 (Japan); Sawada, Hitoshi, E-mail: hsawada@bio.nagoya-u.ac.jp [Sugashima Marine Biological Laboratory, Graduate School of Science, Nagoya University, Sugashima, Toba 517-0004 (Japan)

2014-09-05

Highlights: • GCS1 is a sperm transmembrane protein that is essential for gamete fusion in flowering plants. • The GCS1 gene is present not only in angiosperms but also in unicellular organisms and animals. • NvGCS1 gene is expressed in the testis and GCS1 protein exists in sperm of a sea anemone. • Anti-GCS1 antibodies inhibited the fertilization, showing the participation in fertilization. - Abstract: It has been reported that GCS1 (Generative Cell Specific 1) is a transmembrane protein that is exclusively expressed in sperm cells and is essential for gamete fusion in flowering plants. The GCS1 gene is present not only in angiosperms but also in unicellular organisms and animals, implying the occurrence of a common or ancestral mechanism of GCS1-mediated gamete fusion. In order to elucidate the common mechanism, we investigated the role of GCS1 in animal fertilization using a sea anemone (Cnidaria), Nematostella vectensis. Although the existence of the GCS1 gene in N. vectensis has been reported, the expression of GCS1 in sperm and the role of GCS1 in fertilization are not known. In this study, we showed that the GCS1 gene is expressed in the testis and that GCS1 protein exists in sperm by in situ hybridization and proteomic analysis, respectively. Then we made four peptide antibodies against the N-terminal extracellular region of NvGCS1. These antibodies specifically reacted to NvGCS1 among sperm proteins on the basis of Western analysis and potently inhibited fertilization in a concentration-dependent manner. These results indicate that sperm GCS1 plays a pivotal role in fertilization, most probably in sperm–egg fusion, in a starlet sea anemone, suggesting a common gamete-fusion mechanism shared by eukaryotic organisms.

Responses to high seawater temperatures in zooxanthellate octocorals.

Science.gov (United States)

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

Responses to high seawater temperatures in zooxanthellate octocorals.

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Paul W Sammarco

the Cnidaria in the western Pacific. We hypothesize that this relationship may have taxonomic implications for other obligate zooxanthellate cnidarians subject to bleaching.

Elevated temperature inhibits recruitment of transferrin-positive vesicles and induces iron-deficiency genes expression in Aiptasia pulchella host-harbored Symbiodinium.

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Song, Po-Ching; Wu, Tsung-Meng; Hong, Ming-Chang; Chen, Ming-Chyuan

2015-10-01

Coral bleaching is the consequence of disruption of the mutualistic Cnidaria-dinoflagellate association. Elevated seawater temperatures have been proposed as the most likely cause of coral bleaching whose severity is enhanced by a limitation in the bioavailability of iron. Iron is required by numerous organisms including the zooxanthellae residing inside the symbiosome of cnidarian cells. However, the knowledge of how symbiotic zooxanthellae obtain iron from the host cells and how elevated water temperature affects the association is very limited. Since cellular iron acquisition is known to be mediated through transferrin receptor-mediated endocytosis, a vesicular trafficking pathway specifically regulated by Rab4 and Rab5, we set out to examine the roles of these key proteins in the iron acquisition by the symbiotic Symbiodinium. Thus, we hypothesized that the iron recruitments into symbiotic zooxanthellae-housed symbiosomes may be dependent on rab4/rab5-mediated fusion with vesicles containing iron-bound transferrins and will be retarded under elevated temperature. In this study, we cloned a novel monolobal transferrin (ApTF) gene from the tropical sea anemone Aiptasia pulchella and confirmed that the association of ApTF with A. pulchella Rab4 (ApRab4) or A. pulchella Rab5 (ApRab5) vesicles is inhibited by elevated temperature through immunofluorescence analysis. We confirmed the iron-deficient phenomenon by demonstrating the induced overexpression of iron-deficiency-responsive genes, flavodoxin and high-affinity iron permease 1, and reduced intracellular iron concentration in zooxanthellae under desferrioxamine B (iron chelator) and high temperature treatment. In conclusion, our data are consistent with algal iron deficiency being a contributing factor for the thermal stress-induced bleaching of symbiotic cnidarians. Copyright © 2015 Elsevier Inc. All rights reserved.

Epiphytic invertebrate patterns in coastal lakes along a gradient of salinity and water exchange with the sea

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Obolewski, Krystian; Bąkowska, Martyna

2017-10-01

The species composition and abundance of epiphytic fauna inhabiting common reed (Phragmites australis (Cav.) Trin. ex Steud.) was performed in five coastal lakes in Słowiński National Park (southern Baltic coast in northern Poland). The lakes represent a salinity gradient (from freshwater to β-oligohaline waters) and four types of coastal lakes: (1) lagoon, L (Lake Łebsko, seawater enters it permanently); (2) coastal lake with periodically brackish water, CLB (Lake Gardno); (3) freshwater costal lake, CLF (Lake Smołdzińskie); and (4) coastal dune lakes, CLD (Dołgie Wielkie and Dołgie Małe). Using statistical ordination techniques, we found that the structure of epiphytic fauna (microinvertebrates and macroinvertebrates) is determined primarily by hydrological connectivity (water exchange) with the sea. Canonical Correspondence Analysis, coupled with variance partitioning, showed that hydrological connectivity accounted for 24% of the variation in the invertebrate community, followed by physico-chemical (19%) and trophic (8%) factors. Our results indicate that the assemblages of Ciliata-libera and Cnidaria are characteristic for L (β-oligohaline), Rotifera, Suctoria, Chaetogaster sp., Gastropoda and Trichoptera are characteristic for CLB (limnetic/β-oligohaline), but no taxonomic groups are characteristic for CLF and CLD (both limnetic). The index of multivariate dispersion showed a decreasing trend with the increasing lake isolation from the open sea, except for CLD. However, in terms of the structure of epiphytic fauna, Multi-Response Permutation Procedures showed that CLD significantly differed only from CLB. Our results suggest that the identified characteristic taxonomic groups of plant-associated macroinvertebrates have a high potential to be used as bioindicators of salinity and water exchange with the sea, due to their sensitivity to environmental stress.

Non-intrusive Assessment of Photosystem II and Photosystem I in Whole Coral Tissues

Directory of Open Access Journals (Sweden)

Milán Szabó

2017-08-01

Full Text Available Reef building corals (phylum Cnidaria harbor endosymbiotic dinoflagellate algae (genus Symbiodinium that generate photosynthetic products to fuel their host's metabolism. Non-invasive techniques such as chlorophyll (Chl fluorescence analyses of Photosystem II (PSII have been widely used to estimate the photosynthetic performance of Symbiodinium in hospite. However, since the spatial origin of PSII chlorophyll fluorescence in coral tissues is uncertain, such signals give limited information on depth-integrated photosynthetic performance of the whole tissue. In contrast, detection of absorbance changes in the near infrared (NIR region integrates signals from deeper tissue layers due to weak absorption and multiple scattering of NIR light. While extensively utilized in higher plants, NIR bio-optical techniques are seldom applied to corals. We have developed a non-intrusive measurement method to examine photochemistry of intact corals, based on redox kinetics of the primary electron donor in Photosystem I (P700 and chlorophyll fluorescence kinetics (Fast-Repetition Rate fluorometry, FRRf. Since the redox state of P700 depends on the operation of both PSI and PSII, important information can be obtained on the PSII-PSI intersystem electron transfer kinetics. Under moderate, sub-lethal heat stress treatments (33°C for ~20 min, the coral Pavona decussata exhibited down-regulation of PSII electron transfer kinetics, indicated by slower rates of electron transport from QA to plastoquinone (PQ pool, and smaller relative size of oxidized PQ with concomitant decrease of a specifically-defined P700 kinetics area, which represents the active pool of PSII. The maximum quantum efficiency of PSII (Fv/Fm and functional absorption cross-section of PSII (σPSII remained unchanged. Based on the coordinated response of P700 parameters and PSII-PSI electron transport properties, we propose that simple P700 kinetics parameters as employed here serve as indicators of

Toxicity estimates for diuron and atrazine for the tropical marine cnidarian Exaiptasia pallida and in-hospite Symbiodinium spp. using PAM chlorophyll-a fluorometry.

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Howe, Pelli Louise; Reichelt-Brushett, Amanda Jean; Clark, Malcolm William; Seery, Cliff Ross

2017-06-01

Effective ecotoxicological risk assessments for herbicides in tropical marine environments are restricted by a lack of toxicity data, sensitive test methods and endpoints for relevant species, and this requires rectification. The symbiotic sea anemone Exaiptasia pallida is a suitable test species, representing the phylum Cnidaria and allowing for assessments of toxicological responses of both the animal host and in-hospite Symbiodinium spp. Pulse amplitude modulated (PAM) chlorophyll-a fluorometry is recognised as a valuable ecotoxicological tool, and here newly-developed test methods are presented using PAM fluorometry to measure herbicide effects on photosynthetic efficiency of in-hospite Symbiodinium spp. Additionally, measurements on healthy laboratory-reared E. pallida provide baseline data demonstrating the normal effective quantum yield (EQY) and the maximum electron transport rate (ETR m ) for Symbiodinium spp. in the absence of herbicide stress. Concentration-dependant reductions in the EQY and ETR m occurred during diuron and atrazine exposures; a mean 48-h EC50 (effective concentration; 50%) of 8μg/L of diuron was estimated, however atrazine elicited a much lower toxicity. Twelve-day exposures to 10-200μg/L diuron showed that the greatest EQY effect occurred during the first 48h, with little subsequent change. However, longer exposures to the lowest diuron treatment (1μg/L) showed the lowest EQYs after 96h followed by recovery to control levels within 12d. Furthermore, asexual reproduction was inhibited during 12-d exposures to diuron, and 12-d EC50 values of 100 and 132μg/L were estimated to inhibit successful reproduction of pedal lacerates and juveniles by 50% respectively. This study provides much needed data contributions to species sensitivity curves for development of diuron and atrazine water quality guidelines in tropical marine environments. Copyright © 2017 Elsevier B.V. All rights reserved.

Zoanthid diversity (Anthozoa: Hexacorallia) in the Galapagos Islands: a molecular examination

Science.gov (United States)

Reimer, J. D.; Sinniger, F.; Hickman, C. P.

2008-09-01

Although the Galapagos are famous for their unique biodiversity, many groups of marine invertebrates from this isolated archipelago remain understudied or not investigated. One such group is the zoanthids (Order Zoantharia, =Zoanthidea, =Zoanthiniaria), anthozoans (Cnidaria) found in marine ecosystems worldwide. Zoanthid taxonomy has been in a state of disorganization and neglect due in large part to the morphological plasticity within species and questions about the accuracy of traditionally used morphological and ecological characteristics. However, recent studies utilizing molecular methodology combined with morphology have proven to be very useful in understanding zoanthid diversity. The results of a survey of zoanthids from the Galapagos and the east Pacific are reported in this study. Shallow water (zoanthid specimens were identified using the molecular markers mitochondrial 16S ribosomal DNA (mt 16S rDNA), cytochrome oxidase subunit I (COI) gene, and the internal transcribed spacer of ribosomal DNA (ITS-rDNA). From the collected specimens seven putative zoanthid species-level clades from three known genera ( Zoanthus, Palythoa, Parazoanthus) were identified at the molecular level. These identifications were further supported by morphological and ecological data. While almost all specimens belonged to known zoanthid genera, based on unique molecular and ecological data one group of specimens (designated unknown zoanthid sp. “03-103”) is potentially a novel undescribed genus. Additionally, the remaining three azooxanthellate Parazoanthus clades may also be undescribed new species, but due to the overall lack of zoanthid research and descriptions from neighboring areas (East Pacific, west coast of South America) further research is needed to clearly ascertain this. Additionally, notes on the four observed nominal azooxanthellate zoanthid species and a key to all eight nominal (seven from known genera, one from a potentially new genus) shallow water zoanthid

A genetic approach to the origin of Millepora sp. in the eastern Atlantic

Science.gov (United States)

López, C.; Clemente, S.; Almeida, C.; Brito, A.; Hernández, M.

2015-06-01

Many species have experienced recent range expansions due to human-mediated processes, such as the unintentional transport on ships or plastic waste and ocean warming, which facilitates many tropical species to tolerate living beyond their normal limit of distribution, with a potential impact on autochthonous assemblages. In September 2008, three colonies of the fire coral Millepora sp. (Cnidaria: Hydrozoa) were found on the southeastern coast of Tenerife (Canary Islands), though this species had been previously described to have a circumtropical distribution with Cape Verde Islands as its northern limit of distribution in the eastern Atlantic. The aim of this study was to determine the origin of these new colonies in the Canary Islands (11°N of its previously known northernmost limit of distribution) using variation in the cytochrome oxidase subunit I (COI) gene as a molecular marker. In order to do that, Millepora samples from Tenerife and Cape Verde Islands were collected for molecular analyses, and COI sequences from Caribbean samples listed in GenBank were also included in the analysis. Our results showed that all the specimens from Tenerife were genetically identical, suggesting that the colonization of the Canary Islands was the result of a very recent and strong founder effect. The nucleotide sequences of the samples from the Cape Verde and the Canary Islands were closer to the Caribbean than between themselves, pointing to the Caribbean population as the source population for both archipelagos, through independent founder events. The fact that Millepora sp. arrived to Cape Verde long before arriving to the Canaries (pleistocene fossils have been found in that archipelago) suggests that the habitat requirements for this species did not exist before in the Canarian archipelago. Therefore, the rising seawater temperatures recently registered in the Canary Islands could have facilitated the settlement of reef-forming corals drifting across the two basins of

Interannual variability, growth, reproduction and feeding of Pelagia noctiluca (Cnidaria: Scyphozoa) in the Straits of Messina (Central Mediterranean Sea): Linkages with temperature and diet

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Rosa, S.; Pansera, M.; Granata, A.; Guglielmo, L.

2013-02-01

To identify some of the possible environmental factors stimulating the increasingly frequent outbreaks of the scyphomedusa Pelagia noctiluca in the Straits of Messina, we investigated its abundance, growth, reproduction and feeding over a 4-year period, from 2007 to 2011, at two coastal sites. Using either field investigations and manipulative experiments we show that, among the various factors considered, shifts in water temperature (influencing medusae metabolism, growth and reproduction rates) and the size structure of the zooplankton community (their natural preys) can promote the proliferation of P. noctiluca. In particular, we show that increased temperature let jellyfishes to grow more rapidly and reach exceptional sizes. We also report a peculiar opportunistic behavior of P. noctiluca, which makes this species a potentially strong competitor in the pelagic trophic web of the Straits ecosystem. We therefore propose that more frequent P. noctiluca outbreaks stimulated by increasing sea surface temperature and shifts in their prey availability and composition would become, in the near future, a major cause of ecosystem shift.

Zoantharia (Cnidaria: Anthozoa: Hexacorallia) of the South China Sea and Gulf of Thailand: a species list based on past reports and new photographic records

NARCIS (Netherlands)

Reimer, J.D.; Wee, H.B.; Put, A.; Hoeksema, B.W.

2015-01-01

This study is the first review of Zoantharia species in the South China Sea and Gulf of Thailand. In addition to past literature records, new field observations are added from previously unexamined countries and regions. In total 16 species are listed, 15 of which belong to suborder Brachycnemina,

Mitochondrial and nuclear genes suggest that stony corals are monophyletic but most families of stony corals are not (Order Scleractinia, Class Anthozoa, Phylum Cnidaria.

Directory of Open Access Journals (Sweden)

Hironobu Fukami

Full Text Available Modern hard corals (Class Hexacorallia; Order Scleractinia are widely studied because of their fundamental role in reef building and their superb fossil record extending back to the Triassic. Nevertheless, interpretations of their evolutionary relationships have been in flux for over a decade. Recent analyses undermine the legitimacy of traditional suborders, families and genera, and suggest that a non-skeletal sister clade (Order Corallimorpharia might be imbedded within the stony corals. However, these studies either sampled a relatively limited array of taxa or assembled trees from heterogeneous data sets. Here we provide a more comprehensive analysis of Scleractinia (127 species, 75 genera, 17 families and various outgroups, based on two mitochondrial genes (cytochrome oxidase I, cytochrome b, with analyses of nuclear genes (ss-tubulin, ribosomal DNA of a subset of taxa to test unexpected relationships. Eleven of 16 families were found to be polyphyletic. Strikingly, over one third of all families as conventionally defined contain representatives from the highly divergent "robust" and "complex" clades. However, the recent suggestion that corallimorpharians are true corals that have lost their skeletons was not upheld. Relationships were supported not only by mitochondrial and nuclear genes, but also often by morphological characters which had been ignored or never noted previously. The concordance of molecular characters and more carefully examined morphological characters suggests a future of greater taxonomic stability, as well as the potential to trace the evolutionary history of this ecologically important group using fossils.

Morphology and molecular phylogeny of Paragorgia rubra sp. nov. (Cnidaria: Octocorallia), a new bubblegum coral species from a seamount in the tropical Western Pacific

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Li, Yang; Zhan, Zifeng; Xu, Kuidong

2017-07-01

A new species of bubblegum coral, Paragorgia rubra sp. nov., discovered from a seamount at a water depth of 373 m near the Yap Trench is studied using morphological and molecular approaches. Paragorgia rubra sp. nov. is the fourth species of the genus found in the tropical Western Pacific. The new gorgonian is red-colored, uniplanar, and measures approximately 530 mm high and 440 mm wide, with autozooids distributed only on one side of the colony. Paragorgia rubra sp. nov. is most similar to P. kaupeka Sánchez, 2005, but differs distinctly in the polyp ovals with large and compound protuberances (vs. small and simple conical protuberances) and the medullar spindles possessing simple conical protuberances (vs. compound protuberances). Moreover, P. rubra sp. nov. differs from P. kaupeka in the smaller length/width ratio of surface radiates (1.53 vs. 1.75). The genetic distance of the mtMutS gene between P. rubra sp. nov. and P. kaupeka is 0.66%, while the intraspecific distances within Paragorgia Milne-Edwards & Haime, 1857 except the species P. regalis complex are no more than 0.5%, further supporting the establishment of the new species. Furthermore, the ITS2 secondary structure of P. rubra sp. nov. is also different from those of congeners. Phylogenetic analyses indicate Paragorgia rubra sp. nov. and P. kaupeka form a clade, which branched early within Paragorgia and diversified approximately 15 Mya.

The biogenic reefs formed by the alien polychaete Hydroides dianthus (Serpulidae, Annelida) favor the polyp stage of Aurelia coerulea (Cnidaria, Scyphozoa) in a coastal artificial lake.

Science.gov (United States)

Dong, Zhijun; Sun, Tingting; Wang, Lei

2018-04-01

Blooms of the moon jellyfish Aurelia coerulea frequently occur in coastal waters. The increased availability of substrates for the settlement and proliferation of polyps due to the expansion of artificial structures in coastal areas has been proposed as a possible contributing factor in jellyfish blooms. This paper investigates whether a marine artificial lake (Fenghuang Lake) provides additional substrates for A. coerulea polyps and contributes to jellyfish blooms. High densities of A. coerulea ephyrae were discovered in this lake, with a mean density of 41 individuals/m 3 and a maximum measured density of 128 individuals/m 3 . Meanwhile, A. coerulea ephyrae were also found in the two emptying channels outside the lake, with a mean density of 13 individuals/m 3 . Underwater surveys revealed that dense colonies of A. coerulea polyps occurred mainly on biogenic reefs formed by a polychaete, which was identified as an invasive serpulid species Hydroides dianthus, based on the phylogenetic analysis of mitochondrial COI gene sequences. Our study highlights the potential modification of habitats by the alien polychaete H. dianthus, which might provide complex benthic habits suitable for the settlement and proliferation of A. coerulea polyps and may contribute to jellyfish blooms in the marine artificial lake and nearby coastal waters. Copyright © 2018 Elsevier Ltd. All rights reserved.

Timoides agassizii Bigelow, 1904, little-known hydromedusa (Cnidaria), appears briefly in large numbers off Oman, March 2011, with additional notes about species of the genus Timoides.

Science.gov (United States)

Purushothaman, Jasmine; Kharusi, Lubna Al; Mills, Claudia E; Ghielani, Hamed; Marzouki, Mohammad Al

2013-12-11

A bloom of the hydromedusan jellyfish, Timoides agassizii, occurred in February 2011 off the coast of Sohar, Al Batinah, Sultanate of Oman, in the Gulf of Oman. This species was first observed in 1902 in great numbers off Haddummati Atoll in the Maldive Islands in the Indian Ocean and has rarely been seen since. The species appeared briefly in large numbers off Oman in 2011 and subsequent observation of our 2009 samples of zooplankton from Sohar revealed that it was also present in low numbers (two collected) in one sample in 2009; these are the first records in the Indian Ocean north of the Maldives. Medusae collected off Oman were almost identical to those recorded previously from the Maldive Islands, Papua New Guinea, the Marshall Islands, Guam, the South China Sea, and Okinawa. T. agassizii is a species that likely lives for several months. It was present in our plankton samples together with large numbers of the oceanic siphonophore Physalia physalis only during a single month's samples, suggesting that the temporary bloom off Oman was likely due to the arrival of mature, open ocean medusae into nearshore waters. We see no evidence that T. agassizii has established a new population along Oman, since if so, it would likely have been present in more than one sample period. We are unable to deduce further details of the life cycle of this species from blooms of many mature individuals nearshore, about a century apart. Examination of a single damaged T. agassizii medusa from Guam, calls into question the existence of its congener, T. latistyla, known only from a single specimen.

Distribuição espacial e estrutura das comunidades de antozoários (cnidaria: anthozoa) em substratos consolidados no litoral de Santa Catarina, Sul do Brasil

OpenAIRE

Faria Júnior, Edson

2014-01-01

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas, Programa de Pós-Graduação em Ecologia, Florianópolis, 2014 Um padrão recorrente em comunidades bentônicas marinhas de água rasa é a transição entre comunidades com cnidários zooxantelados por outras dominadas por algas com o aumento da latitude. Pesquisas frequentemente usam fatores ambientais para explicar limites de distribuição e uso de habitat de espécies marinhas, entre eles a temperatura d...

Looking for long-term changes in hydroid assemblages (Cnidaria, Hydrozoa) in Alboran Sea (South-Western Mediterranean): a proposal of a monitoring point for the global warming

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González-Duarte, Manuel María; Megina, Cesar; Piraino, Stefano

2014-12-01

In the last 20-30 years, the temperature of the Mediterranean Sea has increased and global warming is allowing the establishment of tropical-affinity species into more temperate zones. Sessile communities are particularly useful as a baseline for ecological monitoring; however, a lack of historical data series exists for sessile marine organisms without commercial interest. Hydroids are ubiquitous components of the benthic sessile fauna on rocky shores and have been used as bio-indicators of environmental conditions. In this study on the benthic hydroid assemblages of the Chafarinas Islands (Alboran Sea, South-Western Mediterranean), we characterized the hydroid assemblages, identified the bathymetric gradients, and compared them with a previous study carried out in 1991. Hydroid assemblages showed a significant difference both between year and among depths. Furthermore, eight species not present in 1991 were found, including two possible new species and the tropical and subtropical species Sertularia marginata. Due to its strategic position at the entrance of the Mediterranean and the existence of previous data on hydroid assemblages, the Chafarinas Islands are proposed as a possible monitoring point for entrance of Atlantic tropical species into the Mediterranean Sea.

Survey of the radioactive background of some specimens of the biota of Rio de Janeiro coastal waters

International Nuclear Information System (INIS)

Santos, P.L. dos; Santos Gouvea, R. de C. dos; Azevedo Gouvea, V. de.

The natural radioactivity of components known to be bioconcentrators of artificial radionuclides in the coast of Rio de Janeiro was determined by means of sistematical gross alpha and beta radiometry. These data constitute the pre-operational survey, determining the radioactivity levels of these organisms and permiting to establish basic values and their temporal variations, which will serve as a referencial for the detection of eventual increases in the radioactivity introduced in the marine environment during the operational phase of nuclear power plants. Uranium and Potassium were also measured in some samples. The maximum and minimum values obtained after six years of experiment, analysing 14 species of algae and 4 species of animals were: for gross alpha radiometry (0,454 + - 0,162)Bq/g in the ashes of the phaeophita Padina vickersiae and (0,473 + - 0,106)Bq/g in the cnidaria Bunodosoma caissarum, (0,067 + - 0,031)Bq/g in the clorophita Ulva Fasciata and (0,091 + - 0,060)Bq/g in the soft tissues of the bivalve Perna perna. The byssus of this animal presented the highest gross alpha concentration : (1,770 + - 0,708)Bq/g, probably due to its high Uranium concentration, which contributes with 71%, complexed with its main constituent, a scleroprotein. The gross beta concentrations were highest in the algae Chetomorpha antennina (6,63 + - 1,80)Bq/g and in the species Bunodosoma caissarum, with a mean value of (2,60 + - 0,74)Bq/g in the ashes. The lowest concentrations were obtained in the rodophita Plocamium brasiliense, (1,64 + - 0,36)Bq/g, and (1,04 + - 0,30)Bq/g in the byssus of Perna perna. By the theoretical concentration of 40 K, calculated from potassium, the strong contribution of that radionuclide in the gross beta activity of the organisms is stressed. Seven samples of ashes were submitted to analyses by three different laboratories and the intercomparison results showed a reasonable agreement. (Author) [pt

Please mind the gap – Visual census and cryptic biodiversity assessment at central Red Sea coral reefs

KAUST Repository

Pearman, John K.

2016-04-26

Coral reefs harbor the most diverse assemblages in the ocean, however, a large proportion of the diversity is cryptic and, therefore, undetected by standard visual census techniques. Cryptic and exposed communities differ considerably in species composition and ecological function. This study compares three different coral reef assessment protocols: i) visual benthic reef surveys: ii) visual census of Autonomous Reef Monitoring Structures (ARMS) plates; and iii) metabarcoding techniques of the ARMS (including sessile, 106–500 μm and 500–2000 μm size fractions), that target the cryptic and exposed communities of three reefs in the central Red Sea. Visual census showed a dominance of Cnidaria (Anthozoa) and Rhodophyta on the reef substrate, while Porifera, Bryozoa and Rhodophyta were the most abundant groups on the ARMS plates. Metabarcoding, targeting the 18S rRNA gene, significantly increased estimates of the species diversity (p < 0.001); revealing that Annelida were generally the dominant phyla (in terms of reads) of all fractions and reefs. Furthermore, metabarcoding detected microbial eukaryotic groups such as Syndiniophyceae, Mamiellophyceae and Bacillariophyceae as relevant components of the sessile fraction. ANOSIM analysis showed that the three reef sites showed no differences based on the visual census data. Metabarcoding showed a higher sensitivity for identifying differences between reef communities at smaller geographic scales than standard visual census techniques as significant differences in the assemblages were observed amongst the reefs. Comparison of the techniques showed no similar patterns for the visual techniques while the metabarcoding of the ARMS showed similar patterns amongst fractions. Establishing ARMS as a standard tool in reef monitoring will not only advance our understanding of local processes and ecological community response to environmental changes, as different faunal components will provide complementary information but

A “Rosetta Stone” for metazoan zooplankton: DNA barcode analysis of species diversity of the Sargasso Sea (Northwest Atlantic Ocean)

Science.gov (United States)

Bucklin, Ann; Ortman, Brian D.; Jennings, Robert M.; Nigro, Lisa M.; Sweetman, Christopher J.; Copley, Nancy J.; Sutton, Tracey; Wiebe, Peter H.

2010-12-01

Species diversity of the metazoan holozooplankton assemblage of the Sargasso Sea, Northwest Atlantic Ocean, was examined through coordinated morphological taxonomic identification of species and DNA sequencing of a ˜650 base-pair region of mitochondrial cytochrome oxidase I (mtCOI) as a DNA barcode (i.e., short sequence for species recognition and discrimination). Zooplankton collections were made from the surface to 5,000 meters during April, 2006 on the R/V R.H. Brown. Samples were examined by a ship-board team of morphological taxonomists; DNA barcoding was carried out in both ship-board and land-based DNA sequencing laboratories. DNA barcodes were determined for a total of 297 individuals of 175 holozooplankton species in four phyla, including: Cnidaria (Hydromedusae, 4 species; Siphonophora, 47); Arthropoda (Amphipoda, 10; Copepoda, 34; Decapoda, 9; Euphausiacea, 10; Mysidacea, 1; Ostracoda, 27); and Mollusca (Cephalopoda, 8; Heteropoda, 6; Pteropoda, 15); and Chaetognatha (4). Thirty species of fish (Teleostei) were also barcoded. For all seven zooplankton groups for which sufficient data were available, Kimura-2-Parameter genetic distances were significantly lower between individuals of the same species (mean=0.0114; S.D. 0.0117) than between individuals of different species within the same group (mean=0.3166; S.D. 0.0378). This difference, known as the barcode gap, ensures that mtCOI sequences are reliable characters for species identification for the oceanic holozooplankton assemblage. In addition, DNA barcodes allow recognition of new or undescribed species, reveal cryptic species within known taxa, and inform phylogeographic and population genetic studies of geographic variation. The growing database of "gold standard" DNA barcodes serves as a Rosetta Stone for marine zooplankton, providing the key for decoding species diversity by linking species names, morphology, and DNA sequence variation. In light of the pivotal position of zooplankton in ocean

Please mind the gap - Visual census and cryptic biodiversity assessment at central Red Sea coral reefs.

Science.gov (United States)

Pearman, John K; Anlauf, Holger; Irigoien, Xabier; Carvalho, Susana

2016-07-01

Coral reefs harbor the most diverse assemblages in the ocean, however, a large proportion of the diversity is cryptic and, therefore, undetected by standard visual census techniques. Cryptic and exposed communities differ considerably in species composition and ecological function. This study compares three different coral reef assessment protocols: i) visual benthic reef surveys: ii) visual census of Autonomous Reef Monitoring Structures (ARMS) plates; and iii) metabarcoding techniques of the ARMS (including sessile, 106-500 μm and 500-2000 μm size fractions), that target the cryptic and exposed communities of three reefs in the central Red Sea. Visual census showed a dominance of Cnidaria (Anthozoa) and Rhodophyta on the reef substrate, while Porifera, Bryozoa and Rhodophyta were the most abundant groups on the ARMS plates. Metabarcoding, targeting the 18S rRNA gene, significantly increased estimates of the species diversity (p < 0.001); revealing that Annelida were generally the dominant phyla (in terms of reads) of all fractions and reefs. Furthermore, metabarcoding detected microbial eukaryotic groups such as Syndiniophyceae, Mamiellophyceae and Bacillariophyceae as relevant components of the sessile fraction. ANOSIM analysis showed that the three reef sites showed no differences based on the visual census data. Metabarcoding showed a higher sensitivity for identifying differences between reef communities at smaller geographic scales than standard visual census techniques as significant differences in the assemblages were observed amongst the reefs. Comparison of the techniques showed no similar patterns for the visual techniques while the metabarcoding of the ARMS showed similar patterns amongst fractions. Establishing ARMS as a standard tool in reef monitoring will not only advance our understanding of local processes and ecological community response to environmental changes, as different faunal components will provide complementary information but

Comprehensive EST analysis of the symbiotic sea anemone, Anemonia viridis.

Science.gov (United States)

Sabourault, Cécile; Ganot, Philippe; Deleury, Emeline; Allemand, Denis; Furla, Paola

2009-07-23

Coral reef ecosystems are renowned for their diversity and beauty. Their immense ecological success is due to a symbiotic association between cnidarian hosts and unicellular dinoflagellate algae, known as zooxanthellae. These algae are photosynthetic and the cnidarian-zooxanthellae association is based on nutritional exchanges. Maintenance of such an intimate cellular partnership involves many crosstalks between the partners. To better characterize symbiotic relationships between a cnidarian host and its dinoflagellate symbionts, we conducted a large-scale EST study on a symbiotic sea anemone, Anemonia viridis, in which the two tissue layers (epiderm and gastroderm) can be easily separated. A single cDNA library was constructed from symbiotic tissue of sea anemones A. viridis in various environmental conditions (both normal and stressed). We generated 39,939 high quality ESTs, which were assembled into 14,504 unique sequences (UniSeqs). Sequences were analysed and sorted according to their putative origin (animal, algal or bacterial). We identified many new repeated elements in the 3'UTR of most animal genes, suggesting that these elements potentially have a biological role, especially with respect to gene expression regulation. We identified genes of animal origin that have no homolog in the non-symbiotic starlet sea anemone Nematostella vectensis genome, but in other symbiotic cnidarians, and may therefore be involved in the symbiosis relationship in A. viridis. Comparison of protein domain occurrence in A. viridis with that in N. vectensis demonstrated an increase in abundance of some molecular functions, such as protein binding or antioxidant activity, suggesting that these functions are essential for the symbiotic state and may be specific adaptations. This large dataset of sequences provides a valuable resource for future studies on symbiotic interactions in Cnidaria. The comparison with the closest available genome, the sea anemone N. vectensis, as well as

Gene discovery in the threatened elkhorn coral: 454 sequencing of the Acropora palmata transcriptome.

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Nicholas R Polato

Full Text Available BACKGROUND: Cnidarians, including corals and anemones, offer unique insights into metazoan evolution because they harbor genetic similarities with vertebrates beyond that found in model invertebrates and retain genes known only from non-metazoans. Cataloging genes expressed in Acropora palmata, a foundation-species of reefs in the Caribbean and western Atlantic, will advance our understanding of the genetic basis of ecologically important traits in corals and comes at a time when sequencing efforts in other cnidarians allow for multi-species comparisons. RESULTS: A cDNA library from a sample enriched for symbiont free larval tissue was sequenced on the 454 GS-FLX platform. Over 960,000 reads were obtained and assembled into 42,630 contigs. Annotation data was acquired for 57% of the assembled sequences. Analysis of the assembled sequences indicated that 83-100% of all A. palmata transcripts were tagged, and provided a rough estimate of the total number genes expressed in our samples (~18,000-20,000. The coral annotation data contained many of the same molecular components as in the Bilateria, particularly in pathways associated with oxidative stress and DNA damage repair, and provided evidence that homologs of p53, a key player in DNA repair pathways, has experienced selection along the branch separating Cnidaria and Bilateria. Transcriptome wide screens of paralog groups and transition/transversion ratios highlighted genes including: green fluorescent proteins, carbonic anhydrase, and oxidative stress proteins; and functional groups involved in protein and nucleic acid metabolism, and the formation of structural molecules. These results provide a starting point for study of adaptive evolution in corals. CONCLUSIONS: Currently available transcriptome data now make comparative studies of the mechanisms underlying coral's evolutionary success possible. Here we identified candidate genes that enable corals to maintain genomic integrity despite

Gene discovery in the threatened elkhorn coral: 454 sequencing of the Acropora palmata transcriptome.

Science.gov (United States)

Polato, Nicholas R; Vera, J Cristobal; Baums, Iliana B

2011-01-01

Cnidarians, including corals and anemones, offer unique insights into metazoan evolution because they harbor genetic similarities with vertebrates beyond that found in model invertebrates and retain genes known only from non-metazoans. Cataloging genes expressed in Acropora palmata, a foundation-species of reefs in the Caribbean and western Atlantic, will advance our understanding of the genetic basis of ecologically important traits in corals and comes at a time when sequencing efforts in other cnidarians allow for multi-species comparisons. A cDNA library from a sample enriched for symbiont free larval tissue was sequenced on the 454 GS-FLX platform. Over 960,000 reads were obtained and assembled into 42,630 contigs. Annotation data was acquired for 57% of the assembled sequences. Analysis of the assembled sequences indicated that 83-100% of all A. palmata transcripts were tagged, and provided a rough estimate of the total number genes expressed in our samples (~18,000-20,000). The coral annotation data contained many of the same molecular components as in the Bilateria, particularly in pathways associated with oxidative stress and DNA damage repair, and provided evidence that homologs of p53, a key player in DNA repair pathways, has experienced selection along the branch separating Cnidaria and Bilateria. Transcriptome wide screens of paralog groups and transition/transversion ratios highlighted genes including: green fluorescent proteins, carbonic anhydrase, and oxidative stress proteins; and functional groups involved in protein and nucleic acid metabolism, and the formation of structural molecules. These results provide a starting point for study of adaptive evolution in corals. Currently available transcriptome data now make comparative studies of the mechanisms underlying coral's evolutionary success possible. Here we identified candidate genes that enable corals to maintain genomic integrity despite considerable exposure to genotoxic stress over long life

Seasonal monitoring of deep-sea megabenthos in Barkley Canyon cold seep by internet operated vehicle (IOV.

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Carolina Doya

Full Text Available Knowledge of the processes shaping deep-sea benthic communities at seasonal scales in cold-seep environments is incomplete. Cold seeps within highly dynamic regions, such as submarine canyons, where variable current regimes may occur, are particularly understudied. Novel Internet Operated Vehicles (IOVs, such as tracked crawlers, provide new techniques for investigating these ecosystems over prolonged periods. In this study a benthic crawler connected to the NEPTUNE cabled infrastructure operated by Ocean Networks Canada was used to monitor community changes across 60 m2 of a cold-seep area of the Barkley Canyon, North East Pacific, at ~890 m depth within an Oxygen Minimum Zone (OMZ. Short video-transects were run at 4-h intervals during the first week of successive calendar months, over a 14 month period (February 14th 2013 to April 14th 2014. Within each recorded transect video megafauna abundances were computed and changes in environmental conditions concurrently measured. The responses of fauna to environmental conditions as a proxy of seasonality were assessed through analysis of abundances in a total of 438 video-transects (over 92 h of total footage. 7698 fauna individuals from 6 phyla (Cnidaria, Ctenophora, Arthropoda, Echinodermata, Mollusca, and Chordata were logged and patterns in abundances of the 7 most abundant taxa (i.e. rockfish Sebastidae, sablefish Anoplopoma fimbria, hagfish Eptatretus stoutii, buccinids (Buccinoidea, undefined small crabs, ctenophores Bolinopsis infundibulum, and Scyphomedusa Poralia rufescens were identified. Patterns in the reproductive behaviour of the grooved tanner crab (Chionnecetes tanneri were also indicated. Temporal variations in biodiversity and abundance in megabenthic fauna was significantly influenced by variabilities in flow velocity flow direction (up or down canyon, dissolved oxygen concentration and month of study. Also reported here for the first time are transient mass aggregations of

Please mind the gap – Visual census and cryptic biodiversity assessment at central Red Sea coral reefs

KAUST Repository

Pearman, John K.; Anlauf, Holger; Irigoien, Xabier; Carvalho, Susana

2016-01-01

Coral reefs harbor the most diverse assemblages in the ocean, however, a large proportion of the diversity is cryptic and, therefore, undetected by standard visual census techniques. Cryptic and exposed communities differ considerably in species composition and ecological function. This study compares three different coral reef assessment protocols: i) visual benthic reef surveys: ii) visual census of Autonomous Reef Monitoring Structures (ARMS) plates; and iii) metabarcoding techniques of the ARMS (including sessile, 106–500 μm and 500–2000 μm size fractions), that target the cryptic and exposed communities of three reefs in the central Red Sea. Visual census showed a dominance of Cnidaria (Anthozoa) and Rhodophyta on the reef substrate, while Porifera, Bryozoa and Rhodophyta were the most abundant groups on the ARMS plates. Metabarcoding, targeting the 18S rRNA gene, significantly increased estimates of the species diversity (p < 0.001); revealing that Annelida were generally the dominant phyla (in terms of reads) of all fractions and reefs. Furthermore, metabarcoding detected microbial eukaryotic groups such as Syndiniophyceae, Mamiellophyceae and Bacillariophyceae as relevant components of the sessile fraction. ANOSIM analysis showed that the three reef sites showed no differences based on the visual census data. Metabarcoding showed a higher sensitivity for identifying differences between reef communities at smaller geographic scales than standard visual census techniques as significant differences in the assemblages were observed amongst the reefs. Comparison of the techniques showed no similar patterns for the visual techniques while the metabarcoding of the ARMS showed similar patterns amongst fractions. Establishing ARMS as a standard tool in reef monitoring will not only advance our understanding of local processes and ecological community response to environmental changes, as different faunal components will provide complementary information but

Comprehensive EST analysis of the symbiotic sea anemone, Anemonia viridis

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Deleury Emeline

2009-07-01

Full Text Available Abstract Background Coral reef ecosystems are renowned for their diversity and beauty. Their immense ecological success is due to a symbiotic association between cnidarian hosts and unicellular dinoflagellate algae, known as zooxanthellae. These algae are photosynthetic and the cnidarian-zooxanthellae association is based on nutritional exchanges. Maintenance of such an intimate cellular partnership involves many crosstalks between the partners. To better characterize symbiotic relationships between a cnidarian host and its dinoflagellate symbionts, we conducted a large-scale EST study on a symbiotic sea anemone, Anemonia viridis, in which the two tissue layers (epiderm and gastroderm can be easily separated. Results A single cDNA library was constructed from symbiotic tissue of sea anemones A. viridis in various environmental conditions (both normal and stressed. We generated 39,939 high quality ESTs, which were assembled into 14,504 unique sequences (UniSeqs. Sequences were analysed and sorted according to their putative origin (animal, algal or bacterial. We identified many new repeated elements in the 3'UTR of most animal genes, suggesting that these elements potentially have a biological role, especially with respect to gene expression regulation. We identified genes of animal origin that have no homolog in the non-symbiotic starlet sea anemone Nematostella vectensis genome, but in other symbiotic cnidarians, and may therefore be involved in the symbiosis relationship in A. viridis. Comparison of protein domain occurrence in A. viridis with that in N. vectensis demonstrated an increase in abundance of some molecular functions, such as protein binding or antioxidant activity, suggesting that these functions are essential for the symbiotic state and may be specific adaptations. Conclusion This large dataset of sequences provides a valuable resource for future studies on symbiotic interactions in Cnidaria. The comparison with the closest

Morphology and the chemical make-up of the inorganic components of black corals

Energy Technology Data Exchange (ETDEWEB)

Nowak, D.; Florek, M.; Nowak, J. [Department of Chemistry, John Paul II Catholic University of Lublin, 20-718 Lublin (Poland); Kwiatek, W.; Lekki, J. [Institute of Nuclear Physics, Department of Nuclear Spectroscopy, 31-342 Krakow (Poland); Chevallier, P. [former LPS, CEN Saclay et LURE, Universite Paris-Sud, Bat 209D, F-91405 Orsay (France); Hacura, A.; Wrzalik, R. [Institute of Physics, Silesian University, 40-007 Katowice (Poland); Ben-Nissan, B. [Department of Chemistry, Materials and Forensic Sciences, University of Technology, Sydney, PO Box 123, Broadway 2007, NSW (Australia); Van Grieken, R. [Department of Chemistry, University of Antwerp, B-2610 Antwerp (Belgium); Kuczumow, A., E-mail: kuczon@kul.lublin.pl [Department of Chemistry, John Paul II Catholic University of Lublin, 20-718 Lublin (Poland)

2009-04-30

Black corals (Cnidaria, Antipatharia) from three different sources were investigated with the aim of detecting inorganic components and their morphology. In general, the skeleton of black corals was composed of the chitin fibrils admixed with peptides and the chitin presence was confirmed by the X-ray diffraction (XRD), Fourier Transformed Infrared Spectrometry (FTIR) and microRaman Microscopy, the latter giving the opportunity of tracing single fibrils and their location. The composition and concentrations of the inorganic components of the black corals were measured, using a scanning electron microprobe and micro-Particle Induced X-ray Emission ({mu}-PIXE). The application of such instruments enabled the estimation of the constituent distributions in a microscale. The mapping option was the most useful technique of making analyses in these studies, just to reveal the composition of chamber-like cells. Analysis of the morphology and microstructure showed that there were three distinct regions within the coral: a core and the cells encircled with adjacent interface gluing strips. The majority of the elements analyzed were selectively distributed and segregated in a striking way in mentioned distinctive zones of the skeleton and it was detected for the first time. The core area was characterized by the relatively elevated concentrations of Ca. The measurements gave extremely clear images of the distribution of particular elements in the skeletal tissue, with I, Ca, K and Fe much more concentrated in the gluing zones, while C, N, Na and Mg present in the interiors of particular skeletal cells. The distribution of some elements (Mg, Fe) and some compounds (chitin) and functional groups (S-S, C-I) allows differentiating the biological and mechanical functions of particular fragments of the rods. The kinds of elements and their concentrations measured were essentially in compliance with rare data available in the literature. The Raman technique gave the additional

Morphology and the chemical make-up of the inorganic components of black corals

International Nuclear Information System (INIS)

Nowak, D.; Florek, M.; Nowak, J.; Kwiatek, W.; Lekki, J.; Chevallier, P.; Hacura, A.; Wrzalik, R.; Ben-Nissan, B.; Van Grieken, R.; Kuczumow, A.

2009-01-01

Black corals (Cnidaria, Antipatharia) from three different sources were investigated with the aim of detecting inorganic components and their morphology. In general, the skeleton of black corals was composed of the chitin fibrils admixed with peptides and the chitin presence was confirmed by the X-ray diffraction (XRD), Fourier Transformed Infrared Spectrometry (FTIR) and microRaman Microscopy, the latter giving the opportunity of tracing single fibrils and their location. The composition and concentrations of the inorganic components of the black corals were measured, using a scanning electron microprobe and micro-Particle Induced X-ray Emission (μ-PIXE). The application of such instruments enabled the estimation of the constituent distributions in a microscale. The mapping option was the most useful technique of making analyses in these studies, just to reveal the composition of chamber-like cells. Analysis of the morphology and microstructure showed that there were three distinct regions within the coral: a core and the cells encircled with adjacent interface gluing strips. The majority of the elements analyzed were selectively distributed and segregated in a striking way in mentioned distinctive zones of the skeleton and it was detected for the first time. The core area was characterized by the relatively elevated concentrations of Ca. The measurements gave extremely clear images of the distribution of particular elements in the skeletal tissue, with I, Ca, K and Fe much more concentrated in the gluing zones, while C, N, Na and Mg present in the interiors of particular skeletal cells. The distribution of some elements (Mg, Fe) and some compounds (chitin) and functional groups (S-S, C-I) allows differentiating the biological and mechanical functions of particular fragments of the rods. The kinds of elements and their concentrations measured were essentially in compliance with rare data available in the literature. The Raman technique gave the additional

Evolution of the MAGUK protein gene family in premetazoan lineages

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Ruiz-Trillo Iñaki

2010-04-01

Full Text Available Abstract Background Cell-to-cell communication is a key process in multicellular organisms. In multicellular animals, scaffolding proteins belonging to the family of membrane-associated guanylate kinases (MAGUK are involved in the regulation and formation of cell junctions. These MAGUK proteins were believed to be exclusive to Metazoa. However, a MAGUK gene was recently identified in an EST survey of Capsaspora owczarzaki, an unicellular organism that branches off near the metazoan clade. To further investigate the evolutionary history of MAGUK, we have undertook a broader search for this gene family using available genomic sequences of different opisthokont taxa. Results Our survey and phylogenetic analyses show that MAGUK proteins are present not only in Metazoa, but also in the choanoflagellate Monosiga brevicollis and in the protist Capsaspora owczarzaki. However, MAGUKs are absent from fungi, amoebozoans or any other eukaryote. The repertoire of MAGUKs in Placozoa and eumetazoan taxa (Cnidaria + Bilateria is quite similar, except for one class that is missing in Trichoplax, while Porifera have a simpler MAGUK repertoire. However, Vertebrata have undergone several independent duplications and exhibit two exclusive MAGUK classes. Three different MAGUK types are found in both M. brevicollis and C. owczarzaki: DLG, MPP and MAGI. Furthermore, M. brevicollis has suffered a lineage-specific diversification. Conclusions The diversification of the MAGUK protein gene family occurred, most probably, prior to the divergence between Metazoa+choanoflagellates and the Capsaspora+Ministeria clade. A MAGI-like, a DLG-like, and a MPP-like ancestral genes were already present in the unicellular ancestor of Metazoa, and new gene members have been incorporated through metazoan evolution within two major periods, one before the sponge-eumetazoan split and another within the vertebrate lineage. Moreover, choanoflagellates have suffered an independent MAGUK

Sensory Flask Cells in Sponge Larvae Regulate Metamorphosis via Calcium Signaling.

Science.gov (United States)

Nakanishi, Nagayasu; Stoupin, Daniel; Degnan, Sandie M; Degnan, Bernard M

2015-12-01

The Porifera (sponges) is one of the earliest phyletic lineages to branch off the metazoan tree. Although the body-plan of sponges is among the simplest in the animal kingdom and sponges lack nervous systems that communicate environmental signals to other cells, their larvae have sensory systems that generate coordinated responses to environmental cues. In eumetazoans (Cnidaria and Bilateria), the nervous systems of larvae often regulate metamorphosis through Ca(2+)-dependent signal transduction. In sponges, neither the identity of the receptor system that detects an inductive environmental cue (hereafter "metamorphic cues") nor the signaling system that mediates settlement and metamorphosis are known. Using a combination of behavioral assays and surgical manipulations, we show here that specialized epithelial cells-referred to as flask cells-enriched in the anterior third of the Amphimedon queenslandica larva are most likely to be the sensory cells that detect the metamorphic cues. Surgical removal of the region enriched in flask cells in a larva inhibits the initiation of metamorphosis. The flask cell has an apical sensory apparatus with a cilium surrounded by an apical F-actin-rich protrusion, and numerous vesicles, hallmarks of eumetazoan sensory-neurosecretory cells. We demonstrate that these flask cells respond to metamorphic cues by elevating intracellular Ca(2+) levels, and that this elevation is necessary for the initiation of metamorphosis. Taken together, these analyses suggest that sponge larvae have sensory-secretory epithelial cells capable of converting exogenous cues into internal signals via Ca(2+)-mediated signaling, which is necessary for the initiation of metamorphosis. Similarities in the morphology, physiology, and function of the sensory flask cells in sponge larvae with the sensory/neurosecretory cells in eumetazoan larvae suggest this sensory system predates the divergence of Porifera and Eumetazoa. © The Author 2015. Published by Oxford

Strabismus-mediated primary archenteron invagination is uncoupled from Wnt/β-catenin-dependent endoderm cell fate specification in Nematostella vectensis (Anthozoa, Cnidaria: Implications for the evolution of gastrulation

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Kumburegama Shalika

2011-01-01

Full Text Available Abstract Background Gastrulation is a uniquely metazoan character, and its genesis was arguably the key step that enabled the remarkable diversification within this clade. The process of gastrulation involves two tightly coupled events during embryogenesis of most metazoans. Morphogenesis produces a distinct internal epithelial layer in the embryo, and this epithelium becomes segregated as an endoderm/endomesodermal germ layer through the activation of a specific gene regulatory program. The developmental mechanisms that induced archenteron formation and led to the segregation of germ layers during metazoan evolution are unknown. But an increased understanding of development in early diverging taxa at the base of the metazoan tree may provide insights into the origins of these developmental mechanisms. Results In the anthozoan cnidarian Nematostella vectensis, initial archenteron formation begins with bottle cell-induced buckling of the blastula epithelium at the animal pole. Here, we show that bottle cell formation and initial gut invagination in Nematostella requires NvStrabismus (NvStbm, a maternally-expressed core component of the Wnt/Planar Cell Polarity (PCP pathway. The NvStbm protein is localized to the animal pole of the zygote, remains asymmetrically expressed through the cleavage stages, and becomes restricted to the apical side of invaginating bottle cells at the blastopore. Antisense morpholino-mediated NvStbm-knockdown blocks bottle cell formation and initial archenteron invagination, but it has no effect on Wnt/ß-catenin signaling-mediated endoderm cell fate specification. Conversely, selectively blocking Wnt/ß-catenin signaling inhibits endoderm cell fate specification but does not affect bottle cell formation and initial archenteron invagination. Conclusions Our results demonstrate that Wnt/PCP-mediated initial archenteron invagination can be uncoupled from Wnt/ß-catenin-mediated endoderm cell fate specification in Nematostella, and provides evidence that these two processes could have evolved independently during metazoan evolution. We propose a two-step model for the evolution of an archenteron and the evolution of endodermal germ layer segregation. Asymmetric accumulation and activation of Wnt/PCP components at the animal pole of the last common ancestor to the eumetazoa may have induced the cell shape changes that led to the initial formation of an archenteron. Activation of Wnt/ß-catenin signaling at the animal pole may have led to the activation of a gene regulatory network that specified an endodermal cell fate in the archenteron.

Morphological, histopathological and molecular characterization of Thelohanellus theinensis n. sp. (Cnidaria: Myxosporea) infecting an Indian major carp, Labeo bata in a cold water wetland in Punjab (India).

Science.gov (United States)

Gupta, Aditya; Kaur, Harpreet

2017-09-01

A myxozoan parasite belonging to the genus Thelohanellus Kudo, 1933 (Myxosporea, Bivalvulida) was isolated from the gill lamellae of Labeo bata (Hamilton, 1822) inhabiting Ranjit Sagar Wetland in Northern parts of Punjab, India. Histopathology of the infected gills indicated lamellar distortion due to the presence of plasmodia. The intensity of infection was recorded to be moderate as indicated by gill plasmodial index (GPI = 2). The plasmodia were microscopic, ovoid, creamish white, 2.0-4.0 mm in diameter containing 300-400 number of myxospores. The myxospores were broadly pyriform in shape, measuring 8.27 × 4.41 µm, having a prominent pore at the anterior end. The polar capsule was pyriform in shape, measuring 4.15 × 4.10 µm, containing a polar filament coiled perpendicular to the longitudinal axis of myxospore body making 6-7 turns. At molecular level, the analysis of 18S rDNA sequence of T. theinensis n. sp. demonstrated maximum homogeneity of 99 % with T. filli (KR340464) as only 2 gaps were found due to the difference of the last 20 base pairs at the 3' end of T. theinensis n. sp. The current study emphasizes the need for caution when dealing with members of species complex.

Anthopleura radians, a new species of sea anemone (Cnidaria: Actiniaria: Actiniidae from northern Chile, with comments on other species of the genus from the South Pacific Ocean

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Carlos Spano

2017-05-01

Full Text Available A new species of sea anemone, Anthopleura radians n. sp., is described from the intertidal zone of northern Chile and the taxonomic status of the other Anthopleura species from the South Pacific are discussed. A. radians n. sp. is characterized by a yellow-whitish and brown checkerboard-like pattern on the oral disc, adhesive verrucae along the entire column and a series of marginal projections, each bearing a brightly-colored acrorhagus on the oral surface. This is the seventh species of Anthopleura described from the South Pacific Ocean; each one distinguished by a particular combination of differences related to their coloration pattern, presence of zooxanthellae, cnidae, and mode of reproduction. Some of these species have not been reported since their original description and thus require to be taxonomically validated. A. hermaphroditica and A. aureoradiata are synonyms considering the lack of differences seen between live specimens, museum collections and published records. A. radians could also be a junior synonym of A. minima, however, no type material was found for testing this hypothesis. Furthermore, it is crucial to designate neotypes for A. inconspicua, A. rosea and A. minima since there are no name-bearing types reported for these species.

Description and experimental transmission of Tetracapsuloides vermiformis n. sp (Cnidaria: Myxozoa) and guidelines for describing malacosporean species including reinstatement of Buddenbrockia bryozoides n. comb. (syn. Tetracapsula bryozoides)

Czech Academy of Sciences Publication Activity Database

Patra, Sneha; Hartigan, Ashlie; Morris, D.J.; Kodádková, Alena; Holzer, Astrid S.

2017-01-01

Roč. 144, č. 4 (2017), s. 497-511 ISSN 0031-1820 R&D Projects: GA ČR(CZ) GBP505/12/G112 Institutional support: RVO:60077344 Keywords : Buddenbrockia bryozoides n. comb. * Buddenbrockia plumatellae * Malacosporea * morphological variation * Myxozoa * species discrimination * taxonomy * Tetracapsuloides vermiformis n. sp. Subject RIV: EG - Zoology OBOR OECD: Zoology Impact factor: 2.713, year: 2016

The evolution of Dscam genes across the arthropods.

Science.gov (United States)

Armitage, Sophie A O; Freiburg, Rebecca Y; Kurtz, Joachim; Bravo, Ignacio G

2012-04-13

One way of creating phenotypic diversity is through alternative splicing of precursor mRNAs. A gene that has evolved a hypervariable form is Down syndrome cell adhesion molecule (Dscam-hv), which in Drosophila melanogaster can produce thousands of isoforms via mutually exclusive alternative splicing. The extracellular region of this protein is encoded by three variable exon clusters, each containing multiple exon variants. The protein is vital for neuronal wiring where the extreme variability at the somatic level is required for axonal guidance, and it plays a role in immunity where the variability has been hypothesised to relate to recognition of different antigens. Dscam-hv has been found across the Pancrustacea. Additionally, three paralogous non-hypervariable Dscam-like genes have also been described for D. melanogaster. Here we took a bioinformatics approach, building profile Hidden Markov Models to search across species for putative orthologs to the Dscam genes and for hypervariable alternatively spliced exons, and inferring the phylogenetic relationships among them. Our aims were to examine whether Dscam orthologs exist outside the Bilateria, whether the origin of Dscam-hv could lie outside the Pancrustacea, when the Dscam-like orthologs arose, how many alternatively spliced exons of each exon cluster were present in the most common recent ancestor, and how these clusters evolved. Our results suggest that the origin of Dscam genes may lie after the split between the Cnidaria and the Bilateria and supports the hypothesis that Dscam-hv originated in the common ancestor of the Pancrustacea. Our phylogeny of Dscam gene family members shows six well-supported clades: five containing Dscam-like genes and one containing all the Dscam-hv genes, a seventh clade contains arachnid putative Dscam genes. Furthermore, the exon clusters appear to have experienced different evolutionary histories. Dscam genes have undergone independent duplication events in the insects and

The evolution of Dscam genes across the arthropods

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Armitage Sophie AO

2012-04-01

Full Text Available Abstract Background One way of creating phenotypic diversity is through alternative splicing of precursor mRNAs. A gene that has evolved a hypervariable form is Down syndrome cell adhesion molecule (Dscam-hv, which in Drosophila melanogaster can produce thousands of isoforms via mutually exclusive alternative splicing. The extracellular region of this protein is encoded by three variable exon clusters, each containing multiple exon variants. The protein is vital for neuronal wiring where the extreme variability at the somatic level is required for axonal guidance, and it plays a role in immunity where the variability has been hypothesised to relate to recognition of different antigens. Dscam-hv has been found across the Pancrustacea. Additionally, three paralogous non-hypervariable Dscam-like genes have also been described for D. melanogaster. Here we took a bioinformatics approach, building profile Hidden Markov Models to search across species for putative orthologs to the Dscam genes and for hypervariable alternatively spliced exons, and inferring the phylogenetic relationships among them. Our aims were to examine whether Dscam orthologs exist outside the Bilateria, whether the origin of Dscam-hv could lie outside the Pancrustacea, when the Dscam-like orthologs arose, how many alternatively spliced exons of each exon cluster were present in the most common recent ancestor, and how these clusters evolved. Results Our results suggest that the origin of Dscam genes may lie after the split between the Cnidaria and the Bilateria and supports the hypothesis that Dscam-hv originated in the common ancestor of the Pancrustacea. Our phylogeny of Dscam gene family members shows six well-supported clades: five containing Dscam-like genes and one containing all the Dscam-hv genes, a seventh clade contains arachnid putative Dscam genes. Furthermore, the exon clusters appear to have experienced different evolutionary histories. Conclusions Dscam genes have

Cortical cytasters: a highly conserved developmental trait of Bilateria with similarities to Ctenophora

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Salinas-Saavedra Miguel

2011-12-01

Full Text Available Abstract Background Cytasters (cytoplasmic asters are centriole-based nucleation centers of microtubule polymerization that are observable in large numbers in the cortical cytoplasm of the egg and zygote of bilaterian organisms. In both protostome and deuterostome taxa, cytasters have been described to develop during oogenesis from vesicles of nuclear membrane that move to the cortical cytoplasm. They become associated with several cytoplasmic components, and participate in the reorganization of cortical cytoplasm after fertilization, patterning the antero-posterior and dorso-ventral body axes. Presentation of the hypothesis The specific resemblances in the development of cytasters in both protostome and deuterostome taxa suggest that an independent evolutionary origin is unlikely. An assessment of published data confirms that cytasters are present in several protostome and deuterostome phyla, but are absent in the non-bilaterian phyla Cnidaria and Ctenophora. We hypothesize that cytasters evolved in the lineage leading to Bilateria and were already present in the most recent common ancestor shared by protostomes and deuterostomes. Thus, cytasters would be an ancient and highly conserved trait that is homologous across the different bilaterian phyla. The alternative possibility is homoplasy, that is cytasters have evolved independently in different lineages of Bilateria. Testing the hypothesis So far, available published information shows that appropriate observations have been made in eight different bilaterian phyla. All of them present cytasters. This is consistent with the hypothesis of homology and conservation. However, there are several important groups for which there are no currently available data. The hypothesis of homology predicts that cytasters should be present in these groups. Increasing the taxonomic sample using modern techniques uniformly will test for evolutionary patterns supporting homology, homoplasy, or secondary loss of

Extracting phylogenetic signal and accounting for bias in whole-genome data sets supports the Ctenophora as sister to remaining Metazoa.

Science.gov (United States)

Borowiec, Marek L; Lee, Ernest K; Chiu, Joanna C; Plachetzki, David C

2015-11-23

Understanding the phylogenetic relationships among major lineages of multicellular animals (the Metazoa) is a prerequisite for studying the evolution of complex traits such as nervous systems, muscle tissue, or sensory organs. Transcriptome-based phylogenies have dramatically improved our understanding of metazoan relationships in recent years, although several important questions remain. The branching order near the base of the tree, in particular the placement of the poriferan (sponges, phylum Porifera) and ctenophore (comb jellies, phylum Ctenophora) lineages is one outstanding issue. Recent analyses have suggested that the comb jellies are sister to all remaining metazoan phyla including sponges. This finding is surprising because it suggests that neurons and other complex traits, present in ctenophores and eumetazoans but absent in sponges or placozoans, either evolved twice in Metazoa or were independently, secondarily lost in the lineages leading to sponges and placozoans. To address the question of basal metazoan relationships we assembled a novel dataset comprised of 1080 orthologous loci derived from 36 publicly available genomes representing major lineages of animals. From this large dataset we procured an optimized set of partitions with high phylogenetic signal for resolving metazoan relationships. This optimized data set is amenable to the most appropriate and computationally intensive analyses using site-heterogeneous models of sequence evolution. We also employed several strategies to examine the potential for long-branch attraction to bias our inferences. Our analyses strongly support the Ctenophora as the sister lineage to other Metazoa. We find no support for the traditional view uniting the ctenophores and Cnidaria. Our findings are supported by Bayesian comparisons of topological hypotheses and we find no evidence that they are biased by long-branch attraction. Our study further clarifies relationships among early branching metazoan lineages

Caracterización preliminar de los invertebrados bentónicos capturados accidentalmente en la pesca de camarones en el norte del estado de Río de Janeiro, sudeste de Brasil Preliminary characterization of benthic invertebrates caught as by-catch in the shrimp fishery in the north of the Rio de Janeiro State, southeastern Brazil

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Igor David da Costa

2009-01-01

Full Text Available Para caracterizar la biodiversidad de invertebrados bentónicos que componen la fauna asociada a la pesca de camarones en el puerto del Farol de Sao Thomé, costa norte del estado de Río de Janeiro, se realizaron 11 pescas mensuales en el año 2004 con redes de arrastre de fondo, cuya área de operaciones comprende 3-5 mn desde la línea de costa, entre 22°00'S y 22°20'S. Los datos registrados de cada taxon y/o especie se refieren a la frecuencia de ocurrencia, frecuencia numérica, biomasa, índice de Importancia Relativa y abundancia. En total se registraron 27 especies de invertebrados bentónicos de Porifera, Cnidaria, Mollusca, Annelida, Crustácea, Echinodermata y Bryozoa. Crustácea fue el más representativo, tanto en número de ejemplares de Petrochirus diogenes, Hepatus pudibundus y Callinectes ornatos, como en biomasa de P. diogenes y H. pudibundas. En términos de frecuencia de ocurrencia en los muéstreos, 11 especies (40,7% fueron constantes; 6 (22,2% accesorias y 10 (37,0% accidentales.In order to characterize the biodiversity of the benthic invertebrate by-catch associated with the shrimp fishery at Farol de Sao Thome harbor, northern Rio de Janeiro State, Brazil, in 2004, 11 monthly trawls were conducted using bottom trawl nets between 22°00'S and 22°20'S and from 3 to 5 nm from the shoreline. The analyzed data for each talon and/or species include frequency of occurrence, numeric frequency, biomass, index of Relative Importance, and abundance. In total, 27 benthic invertebrate species were recorded, including Peripheral, Cnidarians, Mollusk, Annelid, Crustacea, Echinodermata, and Bryozoa. The most representative group was Crustacea, both in number of specimens (Petrochirus diogenes, Hepatus pudibundus, Callinectes ornatus and in biomass (P. diogenes, H. pudibundus. In terms of the frequency of occurrence in the samples, 11 species (40.7% were constant, 6 species (22.2% were accessories, and 10 species (37.0% were by-catch.

Proximate composition of marine invertebrates from tropical coastal waters, with emphasis on the relationship between nitrogen and protein contents

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Graciela S Diniz

2014-05-01

Full Text Available The chemical profiles of Desmapsamma anchorata, Hymeniacidon heliophila (Porifera, Bunodosoma caissarum, Renilla muelleri (Cnidaria, Aplysia brasiliana, Eledone massyae, Isognomon bicolor (Mollusca, Echinaster brasiliensis, Echinometra lucunter, Holothuria grisea, Lytechinus variegatus (Echinodermata, and Phallusia nigra (Chordata were determined. Hydrosoluble protein was the most abundant class of substances for all species, except for the ascidian Phallusia nigra, in which the carbohydrate content was higher. The percentages of hydrosoluble protein (dry weight, dw varied widely among the invertebrates, ranging from 5.88% (R. muelleri to 47.6% (Eledone massyae of the dw .The carbohydrate content fluctuated from 1.3% (R. muelleri to 18.4% (Aplysia brasiliana of the dw. For most of the species, lipid was the second most abundant class of substances, varying from 2.8% (R. muelleri to 25.3% (Echinaster brasiliensis of the dw. Wide variations were also found for the invertebrates nitrogen content, with the lowest value recorded in the cnidarian R. muelleri (2.02% of the dw and the highest in the molluscan E. massyae (12.7% of the dw. The phosphorus content of the dw varyed from 0.24% (R. muelleri to 1.16% (E. massyae. The amino acid composition varied largely among the species, but for most of the species glycine, arginine, glutamic acid, and aspartic acid were the most abundant amino acids, with histidine and tyrosine among the less abundant amino acids. The actual content of total protein in the samples was calculated by the sum of amino acid residues, establishing dw values that fluctuated from 11.1% (R. muelleri to 66.7% (E. massyae. The proteinaceous nitrogen content was high in all species, with an average value of 97.3% of the total nitrogen. From data of total amino acid residues and total nitrogen, specific nitrogen-to-protein conversion factors were calculated for each species. The nitrogen-to-protein conversion factors ranged from 5.10 to

Genomic organization, evolution, and expression of photoprotein and opsin genes in Mnemiopsis leidyi: a new view of ctenophore photocytes

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Schnitzler Christine E

2012-12-01

Full Text Available Abstract Background Calcium-activated photoproteins are luciferase variants found in photocyte cells of bioluminescent jellyfish (Phylum Cnidaria and comb jellies (Phylum Ctenophora. The complete genomic sequence from the ctenophore Mnemiopsis leidyi, a representative of the earliest branch of animals that emit light, provided an opportunity to examine the genome of an organism that uses this class of luciferase for bioluminescence and to look for genes involved in light reception. To determine when photoprotein genes first arose, we examined the genomic sequence from other early-branching taxa. We combined our genomic survey with gene trees, developmental expression patterns, and functional protein assays of photoproteins and opsins to provide a comprehensive view of light production and light reception in Mnemiopsis. Results The Mnemiopsis genome has 10 full-length photoprotein genes situated within two genomic clusters with high sequence conservation that are maintained due to strong purifying selection and concerted evolution. Photoprotein-like genes were also identified in the genomes of the non-luminescent sponge Amphimedon queenslandica and the non-luminescent cnidarian Nematostella vectensis, and phylogenomic analysis demonstrated that photoprotein genes arose at the base of all animals. Photoprotein gene expression in Mnemiopsis embryos begins during gastrulation in migrating precursors to photocytes and persists throughout development in the canals where photocytes reside. We identified three putative opsin genes in the Mnemiopsis genome and show that they do not group with well-known bilaterian opsin subfamilies. Interestingly, photoprotein transcripts are co-expressed with two of the putative opsins in developing photocytes. Opsin expression is also seen in the apical sensory organ. We present evidence that one opsin functions as a photopigment in vitro, absorbing light at wavelengths that overlap with peak photoprotein light

Unexpected diversity and new species in the sponge-Parazoanthidae association in southern Japan

KAUST Repository

Montenegro, Javier; Sinniger, Frederic; Reimer, James Davis

2015-01-01

© 2015 Elsevier Inc. Currently the genera Parazoanthus (family Parazoanthidae) and Epizoanthus (family Epizoanthidae) are the only sponge-associated zoantharians (Cnidaria, Anthozoa). The Parazoanthidae-sponge associations are widely distributed in tropical and subtropical waters from the intertidal to the deep sea in the Atlantic and Indo-Pacific Oceans. However, the taxonomic identification of both parties is often confused due to variable morphology and wide ecological ranges. In particular, Parazoanthidae species diversity remains poorly understood in the Indo-Pacific. In the present study, the diversity of the sponge-zoanthid association in the Indo-Pacific was investigated with 71 Parazoanthidae specimens collected from 29 different locations in Japan (n= 22), Australia (n= 6) and Florida, USA (n= 1). For all specimens morphological analyses were performed and total DNA was extracted and amplified for four DNA markers (COI-mtDNA, mt 16S-rDNA, ITS-rDNA and ALG11-nuDNA). The combined data demonstrate that the specimens of this study are clearly different from those of all described Parazoanthus species, and lead us to erect Umimayanthus gen. n., within family Parazoanthidae, containing the three newly described species U. chanpuru sp. n., U. miyabi sp. n., U. nakama sp. n. The new genus also includes the previously described species U. parasiticus (Duchassaing and Michelotti, 1860; comb. nov.), previously belonging to the genus Parazoanthus. Neighbor joining, maximum likelihood and Bayesian posterior probability phylogenetic trees clearly demonstrate the monophyly of Umimayanthus gen. n. to the exclusion of all outgroup sequences. The phylogenetic results were also compared to morphological features, and polyp sizes, amount of sand content in tissues, types of connections between polyps, and cnidae data, in particular holotrichs-1, were useful in distinguishing the different species within this new genus. This new genus can be distinguished from all other

Macrobenthic fauna community in the Middle Songkhla Lake, Southern Thailand

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Angsupanich, S.

2005-02-01

Full Text Available A bimonthly investigation of macrobenthic fauna at the area from Ban Pak Khat to Ban Leam Chong Thanon in the Inner Songkhla Lake from February 1998 to February 1999 was undertaken to determine the species richness and abundance. A total of 7 phyla and 161 species were identified. Annelida (58 species, Arthropoda (64 species and Mollusca (23 species were the major phyla while Nemertea (1 species, Platyhelminthes (1 species, Cnidaria (4 species and Chordata (10 species were the minor. Fifty-seven speciesof Polychaete annelids were found. The highest species richness (14 species was in the Nereididae Family, of which Ceratonereis burmensis and Namalycastis indica were predominant. Nephtys sp. and Heteromastus sp. were not so highly abundant but appeared at almost all stations through every sampling month, while Prionospio cirrifera and Pseudopolydora kempi were found in higher densities but with narrower distribution. Ficopomatus sp. and unidentified Terebellidae were not commonly found, but occasionally reached a high density. Amphipods gave the highest species richness (22 species, with Photis longicaudata distributed widely and in all months. Five species of Tanaidaceans were found with Apseudes sapensis the second most dominant (max. 5044 individuals m-2 in February in the overall fauna. Isopoda were not as densely found as tanaidaceans but there were many species (18 species. Cyathura sp.1 was the most dominant isopod. Brachidontes arcuatulus was the most dominant bivalve (max. 29449 individuals m-2 in April, especially at stations with a sand-gravel substrate. The mean density of total macrobenthic fauna among stations ranged from 920 to 10620 ind. m-2 while the monthly densities ranged from 1520 to 6160 ind.m-2. The mean density of macrobenthic fauna was highest in the dry season (April. The species richness among stations ranged from65 to 105 species while varying from 81 to 112 species during the different months. The highest species

Unexpected diversity and new species in the sponge-Parazoanthidae association in southern Japan.

Science.gov (United States)

Montenegro, Javier; Sinniger, Frederic; Reimer, James Davis

2015-08-01

Currently the genera Parazoanthus (family Parazoanthidae) and Epizoanthus (family Epizoanthidae) are the only sponge-associated zoantharians (Cnidaria, Anthozoa). The Parazoanthidae-sponge associations are widely distributed in tropical and subtropical waters from the intertidal to the deep sea in the Atlantic and Indo-Pacific Oceans. However, the taxonomic identification of both parties is often confused due to variable morphology and wide ecological ranges. In particular, Parazoanthidae species diversity remains poorly understood in the Indo-Pacific. In the present study, the diversity of the sponge-zoanthid association in the Indo-Pacific was investigated with 71 Parazoanthidae specimens collected from 29 different locations in Japan (n=22), Australia (n=6) and Florida, USA (n=1). For all specimens morphological analyses were performed and total DNA was extracted and amplified for four DNA markers (COI-mtDNA, mt 16S-rDNA, ITS-rDNA and ALG11-nuDNA). The combined data demonstrate that the specimens of this study are clearly different from those of all described Parazoanthus species, and lead us to erect Umimayanthus gen. n., within family Parazoanthidae, containing the three newly described species U. chanpuru sp. n., U. miyabi sp. n., U. nakama sp. n. The new genus also includes the previously described species U. parasiticus (Duchassaing and Michelotti, 1860; comb. nov.), previously belonging to the genus Parazoanthus. Neighbor joining, maximum likelihood and Bayesian posterior probability phylogenetic trees clearly demonstrate the monophyly of Umimayanthus gen. n. to the exclusion of all outgroup sequences. The phylogenetic results were also compared to morphological features, and polyp sizes, amount of sand content in tissues, types of connections between polyps, and cnidae data, in particular holotrichs-1, were useful in distinguishing the different species within this new genus. This new genus can be distinguished from all other Zoantharia by a unique and

A molecular timescale of eukaryote evolution and the rise of complex multicellular life

Science.gov (United States)

Hedges, S. Blair; Blair, Jaime E.; Venturi, Maria L.; Shoe, Jason L.

2004-01-01

BACKGROUND: The pattern and timing of the rise in complex multicellular life during Earth's history has not been established. Great disparity persists between the pattern suggested by the fossil record and that estimated by molecular clocks, especially for plants, animals, fungi, and the deepest branches of the eukaryote tree. Here, we used all available protein sequence data and molecular clock methods to place constraints on the increase in complexity through time. RESULTS: Our phylogenetic analyses revealed that (i) animals are more closely related to fungi than to plants, (ii) red algae are closer to plants than to animals or fungi, (iii) choanoflagellates are closer to animals than to fungi or plants, (iv) diplomonads, euglenozoans, and alveolates each are basal to plants+animals+fungi, and (v) diplomonads are basal to other eukaryotes (including alveolates and euglenozoans). Divergence times were estimated from global and local clock methods using 20-188 proteins per node, with data treated separately (multigene) and concatenated (supergene). Different time estimation methods yielded similar results (within 5%): vertebrate-arthropod (964 million years ago, Ma), Cnidaria-Bilateria (1,298 Ma), Porifera-Eumetozoa (1,351 Ma), Pyrenomycetes-Plectomycetes (551 Ma), Candida-Saccharomyces (723 Ma), Hemiascomycetes-filamentous Ascomycota (982 Ma), Basidiomycota-Ascomycota (968 Ma), Mucorales-Basidiomycota (947 Ma), Fungi-Animalia (1,513 Ma), mosses-vascular plants (707 Ma), Chlorophyta-Tracheophyta (968 Ma), Rhodophyta-Chlorophyta+Embryophyta (1,428 Ma), Plantae-Animalia (1,609 Ma), Alveolata-plants+animals+fungi (1,973 Ma), Euglenozoa-plants+animals+fungi (1,961 Ma), and Giardia-plants+animals+fungi (2,309 Ma). By extrapolation, mitochondria arose approximately 2300-1800 Ma and plastids arose 1600-1500 Ma. Estimates of the maximum number of cell types of common ancestors, combined with divergence times, showed an increase from two cell types at 2500 Ma to

A molecular timescale of eukaryote evolution and the rise of complex multicellular life

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Venturi Maria L

2004-01-01

Full Text Available Abstract Background The pattern and timing of the rise in complex multicellular life during Earth's history has not been established. Great disparity persists between the pattern suggested by the fossil record and that estimated by molecular clocks, especially for plants, animals, fungi, and the deepest branches of the eukaryote tree. Here, we used all available protein sequence data and molecular clock methods to place constraints on the increase in complexity through time. Results Our phylogenetic analyses revealed that (i animals are more closely related to fungi than to plants, (ii red algae are closer to plants than to animals or fungi, (iii choanoflagellates are closer to animals than to fungi or plants, (iv diplomonads, euglenozoans, and alveolates each are basal to plants+animals+fungi, and (v diplomonads are basal to other eukaryotes (including alveolates and euglenozoans. Divergence times were estimated from global and local clock methods using 20–188 proteins per node, with data treated separately (multigene and concatenated (supergene. Different time estimation methods yielded similar results (within 5%: vertebrate-arthropod (964 million years ago, Ma, Cnidaria-Bilateria (1,298 Ma, Porifera-Eumetozoa (1,351 Ma, Pyrenomycetes-Plectomycetes (551 Ma, Candida-Saccharomyces (723 Ma, Hemiascomycetes-filamentous Ascomycota (982 Ma, Basidiomycota-Ascomycota (968 Ma, Mucorales-Basidiomycota (947 Ma, Fungi-Animalia (1,513 Ma, mosses-vascular plants (707 Ma, Chlorophyta-Tracheophyta (968 Ma, Rhodophyta-Chlorophyta+Embryophyta (1,428 Ma, Plantae-Animalia (1,609 Ma, Alveolata-plants+animals+fungi (1,973 Ma, Euglenozoa-plants+animals+fungi (1,961 Ma, and Giardia-plants+animals+fungi (2,309 Ma. By extrapolation, mitochondria arose approximately 2300-1800 Ma and plastids arose 1600-1500 Ma. Estimates of the maximum number of cell types of common ancestors, combined with divergence times, showed an increase from two cell types at 2500 Ma to ~10

Benthic Community Composition and Seabed Characteristics of a Chukchi Sea Pockmark

Science.gov (United States)

MacDonald, I. R.; Bluhm, B.; Iken, K.; Gagaev, S.; Robinson, S.

2005-12-01

densities of over 50 individuals per square meter. Preliminary analysis of the box core samples: Polychaetes (e.g. Chaetozone setose, Aricidea sp., Ophelina sp., Progoniada sp., Proclea graffi, Protula globifera), Foraminifera, Nemertini, Coronata (Cnidaria tubes), Sipunculida (Golfingia), Bivalvia, Anthozoa.

Unexpected diversity and new species in the sponge-Parazoanthidae association in southern Japan

KAUST Repository

Montenegro, Javier

2015-08-01

© 2015 Elsevier Inc. Currently the genera Parazoanthus (family Parazoanthidae) and Epizoanthus (family Epizoanthidae) are the only sponge-associated zoantharians (Cnidaria, Anthozoa). The Parazoanthidae-sponge associations are widely distributed in tropical and subtropical waters from the intertidal to the deep sea in the Atlantic and Indo-Pacific Oceans. However, the taxonomic identification of both parties is often confused due to variable morphology and wide ecological ranges. In particular, Parazoanthidae species diversity remains poorly understood in the Indo-Pacific. In the present study, the diversity of the sponge-zoanthid association in the Indo-Pacific was investigated with 71 Parazoanthidae specimens collected from 29 different locations in Japan (n= 22), Australia (n= 6) and Florida, USA (n= 1). For all specimens morphological analyses were performed and total DNA was extracted and amplified for four DNA markers (COI-mtDNA, mt 16S-rDNA, ITS-rDNA and ALG11-nuDNA). The combined data demonstrate that the specimens of this study are clearly different from those of all described Parazoanthus species, and lead us to erect Umimayanthus gen. n., within family Parazoanthidae, containing the three newly described species U. chanpuru sp. n., U. miyabi sp. n., U. nakama sp. n. The new genus also includes the previously described species U. parasiticus (Duchassaing and Michelotti, 1860; comb. nov.), previously belonging to the genus Parazoanthus. Neighbor joining, maximum likelihood and Bayesian posterior probability phylogenetic trees clearly demonstrate the monophyly of Umimayanthus gen. n. to the exclusion of all outgroup sequences. The phylogenetic results were also compared to morphological features, and polyp sizes, amount of sand content in tissues, types of connections between polyps, and cnidae data, in particular holotrichs-1, were useful in distinguishing the different species within this new genus. This new genus can be distinguished from all other

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

Marine biodiversity of Aotearoa New Zealand.

Science.gov (United States)

Gordon, Dennis P; Beaumont, Jennifer; MacDiarmid, Alison; Robertson, Donald A; Ahyong, Shane T

2010-08-02

The marine-biodiversity assessment of New Zealand (Aotearoa as known to Māori) is confined to the 200 nautical-mile boundary of the Exclusive Economic Zone, which, at 4.2 million km(2), is one of the largest in the world. It spans 30 degrees of latitude and includes a high diversity of seafloor relief, including a trench 10 km deep. Much of this region remains unexplored biologically, especially the 50% of the EEZ deeper than 2,000 m. Knowledge of the marine biota is based on more than 200 years of marine exploration in the region. The major oceanographic data repository is the National Institute of Water and Atmospheric Research (NIWA), which is involved in several Census of Marine Life field projects and is the location of the Southwestern Pacific Regional OBIS Node; NIWA is also data manager and custodian for fisheries research data owned by the Ministry of Fisheries. Related data sources cover alien species, environmental measures, and historical information. Museum collections in New Zealand hold more than 800,000 registered lots representing several million specimens. During the past decade, 220 taxonomic specialists (85 marine) from 18 countries have been engaged in a project to review New Zealand's entire biodiversity. The above-mentioned marine information sources, published literature, and reports were scrutinized to give the results summarized here for the first time (current to 2010), including data on endemism and invasive species. There are 17,135 living species in the EEZ. This diversity includes 4,315 known undescribed species in collections. Species diversity for the most intensively studied phylum-level taxa (Porifera, Cnidaria, Mollusca, Brachiopoda, Bryozoa, Kinorhyncha, Echinodermata, Chordata) is more or less equivalent to that in the ERMS (European Register of Marine Species) region, which is 5.5 times larger in area than the New Zealand EEZ. The implication is that, when all other New Zealand phyla are equally well studied, total marine

Redescription of Oulactis concinnata (Drayton in Dana, 1846) (Cnidaria: Anthozoa: Actiniidae), an actiniid sea anemone from Chile and Perú with special fighting tentacles; with a preliminary revision of the genera with a “frond-like” marginal ruff

NARCIS (Netherlands)

Häussermann, V.

2003-01-01

Two species of sea anemones with a conspicuous marginal ruff of frond-like structures encompassing the tentacular crown occur on the Chilean coast. Oulactis concinnata (= Isoulactis chilensis) (Drayton in Dana, 1846) is re-described in detail and further information is provided for Oulactis

Patrones de distribución de anémonas de mar chilenas de aguas someras (cnidaria: anthozoa: actiniaria, corallimorpharia); con una discusión de las relaciones taxonómicas y zoogeográficas de la actinofauna del Pacífico sudoriental, el Atlántico sudoccidental y la Antártida

OpenAIRE

Häussermann, Verena; Försterra, Günter

2005-01-01

La presente publicación provee un primer análisis zoogeográfico completo de las anémonas de mar (Actiniaria y Corallimorpharia) de las aguas someras a lo largo de la costa chilena y de sus relaciones con faunas vecinas, basando en un extenso muestreo en los últimos años en combinación con revisiones de la literatura. Desde 1994 hasta 2004 obtuvimos mas de 1000 ejemplares pertenecientes a 32 especies de Actiniaria y Corallimorpharia. Se muestrearon mas de 100 lugares enclavados en el intermare...