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Mark E. Hay - One of the best experts on this subject based on the ideXlab platform.
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Seaweed-Coral Interactions: Variance in Seaweed Allelopathy, Coral Susceptibility, and Potential Effects on
2016Co-Authors: Coral Resilience, Roberta M Bonaldo, Mark E. HayAbstract:Tropical reefs are in global decline with seaweeds commonly replacing corals. Negative associations between macroalgae and corals are well documented, but the mechanisms involved, the dynamics of the interactions, and variance in effects of different macroalgal-coral pairings are poorly investigated. We assessed the frequency, magnitude, and dynamics of macroalgal-coral competition involving allelopathic and non-allelopathic macroalgae on three, spatially grouped pairs of no-take Marine Protected Areas (MPAs) and non-MPAs in Fiji. In non-MPAs, biomass of herbivorous fishes was 70–80% lower, macroalgal cover 4–9 fold higher, macroalgal-coral contacts 5–15 fold more frequent and 23–67 fold more extensive (measured as % of colony margin contacted by macroalgae), and coral cover 51–68 % lower than in MPAs. Coral contacts with allelopathic macroalgae occurred less frequently than expected by chance across all sites, while contact with non-allelopathic macroalgae tended to occur more frequently than expected. Transplants of allelopathic macroalgae (Chlorodesmis fastigiata and Galaxaura filamentosa) against coral edges inflicted damage to Acropora aspera and Pocillopora damicornis more rapidly and extensively than to Porites cylindrica and Porites lobata, which appeared more resistant to these macroalgae. Montipora digitata experienced intermediate damage. Extent of damage from macroalgal contact was independent of coral colony size for each of the 10 macroalgal-coral pairings we established. When natural contacts with Galaxaura filamentosa were removed in the field, recovery was rapid for Porites lobata, but Pocillopora damicornis did no
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competition induces allelopathy but suppresses growth and anti herbivore defence in a chemically rich seaweed
Proceedings of The Royal Society B: Biological Sciences, 2014Co-Authors: Douglas B Rasher, Mark E. HayAbstract:Many seaweeds and terrestrial plants induce chemical defences in response to herbivory, but whether they induce chemical defences against competitors (allelopathy) remains poorly understood. We evaluated whether two tropical seaweeds induce allelopathy in response to competition with a reef-building coral. We also assessed the effects of competition on seaweed growth and seaweed chemical defence against herbivores. Following 8 days of competition with the coral Porites cylindrica, the chemically rich seaweed Galaxaura filamentosa induced increased allelochemicals and became nearly twice as damaging to the coral. However, it also experienced significantly reduced growth and increased palatability to herbivores (because of reduced chemical defences). Under the same conditions, the seaweed Sargassum polycystum did not induce allelopathy and did not experience a change in growth or palatability. This is the first demonstration of induced allelopathy in a seaweed, or of competitors reducing seaweed chemical defences against herbivores. Our results suggest that the chemical ecology of coral–seaweed–herbivore interactions can be complex and nuanced, highlighting the need to incorporate greater ecological complexity into the study of chemical defence.
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seaweed coral interactions variance in seaweed allelopathy coral susceptibility and potential effects on coral resilience
PLOS ONE, 2014Co-Authors: Roberta M Bonaldo, Mark E. HayAbstract:Tropical reefs are in global decline with seaweeds commonly replacing corals. Negative associations between macroalgae and corals are well documented, but the mechanisms involved, the dynamics of the interactions, and variance in effects of different macroalgal-coral pairings are poorly investigated. We assessed the frequency, magnitude, and dynamics of macroalgal-coral competition involving allelopathic and non-allelopathic macroalgae on three, spatially grouped pairs of no-take Marine Protected Areas (MPAs) and non-MPAs in Fiji. In non-MPAs, biomass of herbivorous fishes was 70–80% lower, macroalgal cover 4–9 fold higher, macroalgal-coral contacts 5–15 fold more frequent and 23–67 fold more extensive (measured as % of colony margin contacted by macroalgae), and coral cover 51–68% lower than in MPAs. Coral contacts with allelopathic macroalgae occurred less frequently than expected by chance across all sites, while contact with non-allelopathic macroalgae tended to occur more frequently than expected. Transplants of allelopathic macroalgae (Chlorodesmis fastigiata and Galaxaura filamentosa) against coral edges inflicted damage to Acropora aspera and Pocillopora damicornis more rapidly and extensively than to Porites cylindrica and Porites lobata, which appeared more resistant to these macroalgae. Montipora digitata experienced intermediate damage. Extent of damage from macroalgal contact was independent of coral colony size for each of the 10 macroalgal-coral pairings we established. When natural contacts with Galaxaura filamentosa were removed in the field, recovery was rapid for Porites lobata, but Pocillopora damicornis did not recover and damage continued to expand. As macroalgae increase on overfished tropical reefs, allelopathy could produce feedbacks that suppress coral resilience, prevent coral recovery, and promote the stability of algal beds in habitats previously available to corals.
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Percent change in size of damaged areas (mean ± SE) over time following removal or retention of natural contacts with Galaxaura filamentosa.
2014Co-Authors: Roberta M Bonaldo, Mark E. HayAbstract:Percent change in size of damaged areas (mean ± SE) over time following removal or retention of natural contacts with Galaxaura filamentosa.
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Multivariate grouping of coral exposure treatments using principle components analysis based on 850 differentially expressed Acropora millepora and Montipora digitata genes (both coral and Symbiodinium) relative to controls.
2014Co-Authors: Tonya L. Shearer, Terry W. Snell, Mark E. HayAbstract:All genes included in this analysis are in S2 Table. A = Amphiroa crassa, C = Chlorodesmis fastigiata, G = Galaxaura filamentosa and T = Turbinaria conoides.
Manoel Messias Da Silva Costa - One of the best experts on this subject based on the ideXlab platform.
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Quantitative variation of epiphytic diatoms in Galaxaura rugosa (Nemaliales: Rhodophyta)
Marine Biodiversity Records, 2014Co-Authors: Manoel Messias Da Silva Costa, Sonia Maria Barreto Pereira, Patrícia Campos De Arruda, Enide Eskinazi LeçaAbstract:This study aimed at describing the quantitative variations of epiphytic diatoms in Rhodophyta Galaxaura rugosa , collected in the Fernando de Noronha archipelago (north-eastern Brazil), during two annual periods (June 2006 and June 2007). The distribution of epiphytic diatoms in G. rugosa confirmed the occurrence of a quantitative variation/zoning along the thallus of the analysed host, with an increase in density (cells per gram wet weight of seaweed) of apical portions towards the basal parts of the seaweed, regardless of the collection points and the annual periods. The abundance was characterized by individuals with pennate symmetry with raphe, belonging to the Bacillariophyceae class. This fact is the result of the host being collected in an insular environment with great water movement under the direct action of trade winds and ocean currents for most of the year. The study confirmed that in marine ecosystems with strong hydrodynamics, epiphytic flora tends to comprise species with the largest adhesive strength.
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diatomaceas epifitas em Galaxaura rugosa j ellis solander j v lamouroux rhodophyta no arquipelago de fernando de noronha pernambuco brasil
Acta Botanica Brasilica, 2009Co-Authors: Manoel Messias Da Silva Costa, Sonia Maria Barreto Pereira, Enide Eskinazileca, Maria Elizabeth BandeirapedrosaAbstract:Specimens of Galaxaura rugosa (J. Ellis & Solander) J.V. Lamouroux were collected in June 2006 and June 2007 at three localities in Fernando de Noronha Archipelago (Atalaia, Porto and Cagarras), aiming to identify the epiphytic diatom flora that inhabits the algae thallus. A total of 52 taxa were identified, distributed in the classes Coscinodiscophyceae (19%), Fragilariophyceae (21%) and Bacillariophyceae (60%) with 81% dominance of individuals with pinnate symmetry. The following species characterized the floristic diatom structure being considered very frequent: Amphora sp., Biddulphia biddulphiana (J.E. Smith) Boyer, Cocconeis scutellum Ehrenberg, Diploneis bombus Ehrenberg, Grammatophora marina (Lyngbye) Kutzing, Mastogloia binotata (Grunow) Cleve, Navicula longa Grunow, Nitzschia sp., Psammodiscus nitidus (Gregory) Round in Mann, Rhabdonema adriaticum Kutzing, Trachyneis aspera (Ehrenberg) Cleve e Tryblionella coarctata (Grunow) Mann. Specific diversity was medium to high, with lower values for the blooming of Amphora sp. (49.3%), Mastogloia binotata (42.1%) and Nitzschia sp. (62.5%).
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Diatomáceas epífitas em Galaxaura rugosa (J. Ellis & Solander) J.V. Lamouroux (Rhodophyta) no Arquipélago de Fernando de Noronha, PE, Nordeste do Brasil Epiphytic diatoms on Galaxaura rugosa (J. Ellis & Solander) J.V. Lamouroux (Rhodophyta) in Fernan
Sociedade Botânica do Brasil, 2009Co-Authors: Manoel Messias Da Silva Costa, Sonia Maria Barreto Pereira, Enide Eskinazi-leça, Maria Elizabeth Bandeira-pedrosaAbstract:Exemplares de Galaxaura rugosa (J. Ellis & Solander) J.V. Lamouroux foram coletados nos meses de junho/2006 e junho/2007, em três localidades do Arquipélago de Fernando de Noronha (Atalaia, Porto e Cagarras), com o objetivo de identificar a flora das diatomáceas epífitas que habita o talo da alga. Foram identificados 52 táxons distribuídos nas classes: Coscinodiscophyceae (19%), Fragilariophyceae (21%) e Bacillariophyceae (60%) denotando uma dominância de indivíduos com simetria bilateral, os quais corresponderam a 81% da flora identificada. As seguintes espécies caracterizaram a estrutura florística das diatomáceas, pois foram encontradas em mais de 70% das amostras analisadas: Amphora sp., Biddulphia biddulphiana (J.E. Smith) Boyer, Cocconeis scutellum Ehrenberg, Diploneis bombus Ehrenberg, Grammatophora marina (Lyngbye) Kützing, Mastogloia binotata (Grunow) Cleve, Navicula longa Grunow, Nitzschia sp., Psammodiscus nitidus (Gregory) Round in Mann, Rhabdonema adriaticum Kützing, Trachyneis aspera (Ehrenberg) Cleve e Tryblionella coarctata (Grunow) Mann. A diversidade específica variou entre média à alta, com os menores valores correspondendo aos florescimentos de Amphora sp. (49,3%), Mastogloia binotata (42,1%) e Nitzschia sp. (62,5%).Specimens of Galaxaura rugosa (J. Ellis & Solander) J.V. Lamouroux were collected in June 2006 and June 2007 at three localities in Fernando de Noronha Archipelago (Atalaia, Porto and Cagarras), aiming to identify the epiphytic diatom flora that inhabits the algae thallus. A total of 52 taxa were identified, distributed in the classes Coscinodiscophyceae (19%), Fragilariophyceae (21%) and Bacillariophyceae (60%) with 81% dominance of individuals with pinnate symmetry. The following species characterized the floristic diatom structure being considered very frequent: Amphora sp., Biddulphia biddulphiana (J.E. Smith) Boyer, Cocconeis scutellum Ehrenberg, Diploneis bombus Ehrenberg, Grammatophora marina (Lyngbye) Kützing, Mastogloia binotata (Grunow) Cleve, Navicula longa Grunow, Nitzschia sp., Psammodiscus nitidus (Gregory) Round in Mann, Rhabdonema adriaticum Kützing, Trachyneis aspera (Ehrenberg) Cleve e Tryblionella coarctata (Grunow) Mann. Specific diversity was médium to high, with lower values for the blooming of Amphora sp. (49.3%), Mastogloia binotata (42.1%) and Nitzschia sp. (62.5%)
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Diatomáceas epífitas em Galaxaura rugosa (J.Ellis & Solander) J.V.Lamouroux (Rhodophyta) no arquipélago de Fernando de Noronha,Pernambuco,Brasil
Universidade Federal Rural de Pernambuco, 2008Co-Authors: Manoel Messias Da Silva CostaAbstract:As macroalgas marinhas são de primordial importância nos ecossistemas costeiros, pois são consideradas como produtores primários e responsáveis pela transferência de energia para diversos níveis tróficos. Além disso, seus talos suportam vários organismos, tanto animais como vegetais, os quais contribuem para o aumento da produtividade de zonas costeiras de todos os oceanos. Exemplares da rodofíta Galaxaura rugosa (J. Ellis & Solander) J.V. Lamouroux, foram coletados nos meses de junho de 2006 e junho de 2007, em três localidades do Arquipélago de Fernando de Noronha (Praias de Atalaia, Porto e Cagarras), com o objetivo de identificar e quantificar a flora das diatomáceas epífita que habita o talo da alga. Foram identificados 52 táxons distribuídos nas classes Coscinodiscophyceae (19%), Fragilariophyceae (21%) e Bacillariophyceae (60%), com dominância de indivíduos de simetria penada, correspondente a 81%. As seguintes espécies caracterizaram a estrutura florística das diatomáceas, por estarem presentes em mais de 70% das amostras analisadas e, assim, consideradas muitofreqüentes: Diploneis bombus Ehrenberg, Nitzschia sp., Amphora sp., Biddulphia biddulphiana (J.E. Smith) Boyer, Grammatophora marina (Lyngbye)Kutzing, Mastogloia binotata (Grunow) Cleve, Tryblionella coarctata (Grunow) Mann, Navicula longa Grunow, Trachyneis aspera (Ehrenberg) Cleve, Psammodiscus nitidus (Gregory) Round in Mann, Rhabdonema adriaticum Kützing e Cocconeis scutellum Ehrenberg. A densidade total das diatomáceas não apresentou variações significativas entre as diversas partes da alga como também entre os três locais de coleta, com o valor mínimo de 5.000 cel.g-1.peso fresco da alga, encontrado na parte apical de exemplares coletados na praia de Atalaia, e o máximo de 60.000 cel.g-1.peso fresco da alga, na parte basal de exemplares da Praia de Porto. Os resultados confirmaram que a rodofíta Galaxaura rugosa, mostrou-se um bom hospedeiro para fixação das diatomáceas epífitas, tendo sido observado a ocorrência desses organismos em todo o talo dos exemplares coletados, com maiores densidades nas partes basais, confirmando a importância dessas microalgas como produtores primários nas diversas praias de Fernando de Noronha.Marine macroalgae are of fundamental importance in coastal ecosystems once they are primary producers and responsible for energy transference to several trophic levels. Besides, their stems support several organisms, both animals and plants which contribute to productivity increase in the coastal zones of the whole oceans. The Rhodophyta specimens, Galaxaura rugosa (J. Ellis & Solander) J.V. Lamouroux, were collected in June, 2006 and June, 2007 at three localities from Fernando de Noronha Archipelago (Atalaia, Porto and Cagarras) aiming to identify and quantify the epiphyte diatoms flora inhabiting the algae thallus. A total of 52 taxa were identified being distributed in the classes Coscinodiscophyceae (19%), Fragilariophyceae (21%) and Bacillariophyceae (60%), with 81% dominance of individuals with pennate symmetry. The following species characterized the floristic diatoms structure being considered very frequent once they are present in more than 70% samples analyzed: Diploneis bombus Ehrenberg, Nitzschia sp., Amphora sp., Biddulphia biddulphiana (J.E. Smith) Boyer, Grammatophora marina (Lyngbye) Kützing, Mastogloia binotata (Grunow) Cleve, Tryblionella coarctata (Grunow) Mann, Naviculalonga Grunow, Trachyneis aspera (Ehrenberg) Cleve, Psammodiscus nitidus (Gregory) Round in Mann, Rhabdonema adriaticum Kützing and Cocconeis scutellum Ehrenberg. Total diatoms density presented no significant variations among the several parts of the algae as well as among the three sampling sites presenting the minimum value of 5.000 cell.g-1.algae fresh weight in the apical part of specimens sampled in the Atalaia beach, and the maximum of 60.000 cell.g-1.algae fresh weight in the basal part of specimens from Porto beach. Results confirm that the Rhodophyta Galaxaura rugosa is a good hostess for epiphyte diatoms fixation having been observed the occurrence of these organisms in the whole stem of specimens collected with the higher densities in the basal parts, confirming the importance of these microalgae as primary producers at the diverse beaches of Fernando de Noronha
Roberta A Townsend - One of the best experts on this subject based on the ideXlab platform.
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an examination of linnaean and pre linnaean taxa referable to Galaxaura and tricleocarpa Galaxauraceae rhodophyta
Botanical Journal of the Linnean Society, 1993Co-Authors: John M. Huisman, Roberta A TownsendAbstract:An examination of the material used by Linnaeus in the description of two species of Eschara has shown them to be members of the Galaxauraceae (Rhodophyta). Eschara divaricata Linnaeus is conspecific with Galaxaura cohaerens Kjellman and Eschara fragilis Linnaeus is conspecific with Tricleocarpa oblongata (Ellis & Sol.) Huisman & Borowitzka. Thus the combinations Galaxaura divaricata (L.) Huisman & Townsend and Tricleocarpa fragilis (L.) Huisman & Townsend are proposed. Material from the Plukenet and Sloane herbaria, which has been associated with both E. fragilis and Galaxaura rugosa (Ellis & Sol.) Lamouroux (the type of the generic name), was found to be a mixture of Galaxaura rugosa, Galaxaura obtusata (Ellis & Sol.) Lamouroux, and Tricleocarpa cylindrica (Ellis & Sol.) Huisman & Borowitzka.
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regular articlean examination of linnaean and pre linnaean taxa referable to Galaxaura and tricleocarpa Galaxauraceae rhodophyta
Botanical Journal of the Linnean Society, 1993Co-Authors: John M. Huisman, Roberta A TownsendAbstract:An examination of the material used by Linnaeus in the description of two species of Eschara has shown them to be members of the Galaxauraceae (Rhodophyta). Eschara divaricata Linnaeus is conspecific with Galaxaura cohaerens Kjellman and Eschara fragilis Linnaeus is conspecific with Tricleocarpa oblongata (Ellis & Sol.) Huisman & Borowitzka. Thus the combinations Galaxaura divaricata (L.) Huisman & Townsend and Tricleocarpa fragilis (L.) Huisman & Townsend are proposed. Material from the Plukenet and Sloane herbaria, which has been associated with both E. fragilis and Galaxaura rugosa (Ellis & Sol.) Lamouroux (the type of the generic name), was found to be a mixture of Galaxaura rugosa, Galaxaura obtusata (Ellis & Sol.) Lamouroux, and Tricleocarpa cylindrica (Ellis & Sol.) Huisman & Borowitzka.
John M. Huisman - One of the best experts on this subject based on the ideXlab platform.
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a monographic account of australian species of amphiroa corallinaceae rhodophyta
Australian Systematic Botany, 2013Co-Authors: Adele S. Harvey, John M. Huisman, Wm J Woelkerling, Carlos Frederico D GurgelAbstract:The first Australia-wide monograph of Amphiroa (Corallinaceae, Rhodophyta) based on the morphological–anatomical species concept has confirmed the occurrence of nine species (A. anceps, A. beauvoisii, A. crassa, A. exilis, A. foliacea, A. fragilissima, A. gracilis, A. klochkovana, A. tribulus) and provides a basis for future molecular-systematics studies. A comparative analysis of 285 specimens from 121 localities, along with type material examinations, yielded clear evidence that nine characters associated with the vegetative system and tetrasporangial conceptacles were diagnostically significant at species level. Detailed accounts of each species are presented, along with an identification key, data on type specimens, species comparisons and biogeographic notes. A. foliacea is epitypified. Brief accounts of 34 additional taxa reported from Australia and at some stage ascribed to Amphiroa are included. Galaxaura versicolor and Amphiroa galaxauroides are heterotypic synonyms of A. anceps; recognition of A. anastomosans, A. ephedraea and A. nobilis as distinct species requires further evaluation; and A. dilatata and A. gaillonii are species of uncertain status. Amphiroa ephedraea is lectotypified. The remaining 27 names involve nomina nuda, illegitimate names, orthographic variants or taxa now excluded from Amphiroa.
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phylogenetic study of the nemaliales rhodophyta based on large subunit ribosomal dna sequences supports segregation of the scinaiaceae fam nov and resurrection of dichotomaria lamarck
Phycological Research, 2004Co-Authors: John M. Huisman, James T. Harper, Gary W. SaundersAbstract:Gene sequence data have been newly obtained for 18 species in 13 genera of the order Nemaliales (Rhodophyta), allowing for the first time a relatively comprehensive molecular phylogenetic appraisal of the order. The phylogenetic trees generated from these data support the recognition of three families: (i) the Liagoraceae as presently constituted; (ii) a reduced Galaxauraceae including Actinotrichia, Galaxaura (sensu lato), and Tricleocarpa; and (iii) a new family, Scinaiaceae, segregated from the Galaxauraceae and including the genera Scinaia, Gloiophloea, Nothogenia, and probably Whidbeyella. The four genera of the Scinaiaceae differ from the newly circumscribed Galaxauraceae in being uncalcified, and having heteromorphic life histories in which the tetrasporophyte is much reduced and filamentous or crustose. This type of life history is found in only Tricleocarpa of the Galaxauraceae. The results also show Galaxaura to be para/polyphyletic if Actinotrichia and Tricleocarpa are recognized. To remedy this, the Galaxaura marginata species complex, Galaxaura diesingiana, and Galaxaura obtusata are removed from the genus and placed in the resurrected Dichotomaria Lamarck. Galaxaura marginata, presently thought to be wide-ranging and morphologically variable, is shown to comprise several species. As a consequence, Galaxaura tenera Kjellman and Brachycladia australis Sonder are removed from the synonymy of G. marginata and restored as independent species in Dichotomaria for South African and Australian isolates, respectively. The Liagoraceae is shown to encompass genera previously placed in the segregate families Nemaliaceae and Dermonemataceae, and the value of the reproductive characters used to define those taxa is discussed.
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Studies of Hawaiian Galaxauraceae (Nemaliales, Rhodophyta): Large subunit rDNA gene sequences support conspecificity of Galaxaura rugosa and G. subverticillata
Cryptogamie Algologie, 2004Co-Authors: John M. Huisman, Alison R. Sherwood, Isabella A. AbbottAbstract:Species of the genus Galaxaura are unusual in having gametophyte and tetrasporophyte phases that, while somewhat similar in stature, display markedly different cortical morphologies. These differences have, in the past, led to many species being erected that represent no more than life-history phases of a single species. This paper discusses the identity of the tetrasporophyte phase of G. rugosa, the type of the genus, and concludes that it, at least, includes G. subverticillata, a species regarded as independent in several recent publications. Evidence for this conclusion resides in a comparison of large subunit rDNA sequence data from G. rugosa and "G. subverticillata" collected in Hawaii, in situ observations, plus a review of historical and recent morphological studies. In addition, evidence is presented to support the inclusion of plants with both flattened and subterete branch morphologies in Dichotomaria marginata (Ellis et Solander) Lamarck.
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an examination of linnaean and pre linnaean taxa referable to Galaxaura and tricleocarpa Galaxauraceae rhodophyta
Botanical Journal of the Linnean Society, 1993Co-Authors: John M. Huisman, Roberta A TownsendAbstract:An examination of the material used by Linnaeus in the description of two species of Eschara has shown them to be members of the Galaxauraceae (Rhodophyta). Eschara divaricata Linnaeus is conspecific with Galaxaura cohaerens Kjellman and Eschara fragilis Linnaeus is conspecific with Tricleocarpa oblongata (Ellis & Sol.) Huisman & Borowitzka. Thus the combinations Galaxaura divaricata (L.) Huisman & Townsend and Tricleocarpa fragilis (L.) Huisman & Townsend are proposed. Material from the Plukenet and Sloane herbaria, which has been associated with both E. fragilis and Galaxaura rugosa (Ellis & Sol.) Lamouroux (the type of the generic name), was found to be a mixture of Galaxaura rugosa, Galaxaura obtusata (Ellis & Sol.) Lamouroux, and Tricleocarpa cylindrica (Ellis & Sol.) Huisman & Borowitzka.
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regular articlean examination of linnaean and pre linnaean taxa referable to Galaxaura and tricleocarpa Galaxauraceae rhodophyta
Botanical Journal of the Linnean Society, 1993Co-Authors: John M. Huisman, Roberta A TownsendAbstract:An examination of the material used by Linnaeus in the description of two species of Eschara has shown them to be members of the Galaxauraceae (Rhodophyta). Eschara divaricata Linnaeus is conspecific with Galaxaura cohaerens Kjellman and Eschara fragilis Linnaeus is conspecific with Tricleocarpa oblongata (Ellis & Sol.) Huisman & Borowitzka. Thus the combinations Galaxaura divaricata (L.) Huisman & Townsend and Tricleocarpa fragilis (L.) Huisman & Townsend are proposed. Material from the Plukenet and Sloane herbaria, which has been associated with both E. fragilis and Galaxaura rugosa (Ellis & Sol.) Lamouroux (the type of the generic name), was found to be a mixture of Galaxaura rugosa, Galaxaura obtusata (Ellis & Sol.) Lamouroux, and Tricleocarpa cylindrica (Ellis & Sol.) Huisman & Borowitzka.
Costa,manoel Messias Da Silva - One of the best experts on this subject based on the ideXlab platform.
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Diatomáceas epífitas em Galaxaura rugosa (J. Ellis & Solander) J.V. Lamouroux (Rhodophyta) no Arquipélago de Fernando de Noronha, PE, Nordeste do Brasil
Sociedade Botânica do Brasil, 2009Co-Authors: Costa,manoel Messias Da Silva, Pereira,sonia Maria Barreto, Bandeira-pedrosa,maria ElizabethAbstract:Exemplares de Galaxaura rugosa (J. Ellis & Solander) J.V. Lamouroux foram coletados nos meses de junho/2006 e junho/2007, em três localidades do Arquipélago de Fernando de Noronha (Atalaia, Porto e Cagarras), com o objetivo de identificar a flora das diatomáceas epífitas que habita o talo da alga. Foram identificados 52 táxons distribuídos nas classes: Coscinodiscophyceae (19%), Fragilariophyceae (21%) e Bacillariophyceae (60%) denotando uma dominância de indivíduos com simetria bilateral, os quais corresponderam a 81% da flora identificada. As seguintes espécies caracterizaram a estrutura florística das diatomáceas, pois foram encontradas em mais de 70% das amostras analisadas: Amphora sp., Biddulphia biddulphiana (J.E. Smith) Boyer, Cocconeis scutellum Ehrenberg, Diploneis bombus Ehrenberg, Grammatophora marina (Lyngbye) Kützing, Mastogloia binotata (Grunow) Cleve, Navicula longa Grunow, Nitzschia sp., Psammodiscus nitidus (Gregory) Round in Mann, Rhabdonema adriaticum Kützing, Trachyneis aspera (Ehrenberg) Cleve e Tryblionella coarctata (Grunow) Mann. A diversidade específica variou entre média à alta, com os menores valores correspondendo aos florescimentos de Amphora sp. (49,3%), Mastogloia binotata (42,1%) e Nitzschia sp. (62,5%)
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Diatomáceas epífitas em Galaxaura rugosa (J.Ellis & Solander) J.V.Lamouroux (Rhodophyta) no arquipélago de Fernando de Noronha,Pernambuco,Brasil
Programa de Pós-Graduação em Botânica, 2008Co-Authors: Costa,manoel Messias Da SilvaAbstract:As macroalgas marinhas são de primordial importância nos ecossistemas costeiros, pois são consideradas como produtores primários e responsáveis pela transferência de energia para diversos níveis tróficos. Além disso, seus talos suportam vários organismos, tanto animais como vegetais, os quais contribuem para o aumento da produtividade de zonas costeiras de todos os oceanos. Exemplares da rodofíta Galaxaura rugosa (J. Ellis & Solander) J.V. Lamouroux, foram coletados nos meses de junho de 2006 e junho de 2007, em três localidades do Arquipélago de Fernando de Noronha (Praias de Atalaia, Porto e Cagarras), com o objetivo de identificar e quantificar a flora das diatomáceas epífita que habita o talo da alga. Foram identificados 52 táxons distribuídos nas classes Coscinodiscophyceae (19%), Fragilariophyceae (21%) e Bacillariophyceae (60%), com dominância de indivíduos de simetria penada, correspondente a 81%. As seguintes espécies caracterizaram a estrutura florística das diatomáceas, por estarem presentes em mais de 70% das amostras analisadas e, assim, consideradas muitofreqüentes: Diploneis bombus Ehrenberg, Nitzschia sp., Amphora sp., Biddulphia biddulphiana (J.E. Smith) Boyer, Grammatophora marina (Lyngbye)Kutzing, Mastogloia binotata (Grunow) Cleve, Tryblionella coarctata (Grunow) Mann, Navicula longa Grunow, Trachyneis aspera (Ehrenberg) Cleve, Psammodiscus nitidus (Gregory) Round in Mann, Rhabdonema adriaticum Kützing e Cocconeis scutellum Ehrenberg. A densidade total das diatomáceas não apresentou variações significativas entre as diversas partes da alga como também entre os três locais de coleta, com o valor mínimo de 5.000 cel.g-1.peso fresco da alga, encontrado na parte apical de exemplares coletados na praia de Atalaia, e o máximo de 60.000 cel.g-1.peso fresco da alga, na parte basal de exemplares da Praia de Porto. Os resultados confirmaram que a rodofíta Galaxaura rugosa, mostrou-se um bom hospedeiro para fixação das diatomáceas epífitas, tendo sido observado a ocorrência desses organismos em todo o talo dos exemplares coletados, com maiores densidades nas partes basais, confirmando a importância dessas microalgas como produtores primários nas diversas praias de Fernando de Noronha.Marine macroalgae are of fundamental importance in coastal ecosystems once they are primary producers and responsible for energy transference to several trophic levels. Besides, their stems support several organisms, both animals and plants which contribute to productivity increase in the coastal zones of the whole oceans. The Rhodophyta specimens, Galaxaura rugosa (J. Ellis & Solander) J.V. Lamouroux, were collected in June, 2006 and June, 2007 at three localities from Fernando de Noronha Archipelago (Atalaia, Porto and Cagarras) aiming to identify and quantify the epiphyte diatoms flora inhabiting the algae’ thallus. A total of 52 taxa were identified being distributed in the classes Coscinodiscophyceae (19%), Fragilariophyceae (21%) and Bacillariophyceae (60%), with 81% dominance of individuals with pennate symmetry. The following species characterized the floristic diatoms structure being considered very frequent once they are present in more than 70% samples analyzed: Diploneis bombus Ehrenberg, Nitzschia sp., Amphora sp., Biddulphia biddulphiana (J.E. Smith) Boyer, Grammatophora marina (Lyngbye) Kützing, Mastogloia binotata (Grunow) Cleve, Tryblionella coarctata (Grunow) Mann, Naviculalonga Grunow, Trachyneis aspera (Ehrenberg) Cleve, Psammodiscus nitidus (Gregory) Round in Mann, Rhabdonema adriaticum Kützing and Cocconeis scutellum Ehrenberg. Total diatoms density presented no significant variations among the several parts of the algae as well as among the three sampling sites presenting the minimum value of 5.000 cell.g-1.algae fresh weight in the apical part of specimens sampled in the Atalaia beach, and the maximum of 60.000 cell.g-1.algae fresh weight in the basal part of specimens from Porto beach. Results confirm that the Rhodophyta Galaxaura rugosa is a good hostess for epiphyte diatoms fixation having been observed the occurrence of these organisms in the whole stem of specimens collected with the higher densities in the basal parts, confirming the importance of these microalgae as primary producers at the diverse beaches of Fernando de Noronha.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPE
