Diversidade de espécies de macroalgas associadas ao Manguezal da Ilha Barnabé, Baixada Santista, SP, Brasil, com base em \"DNA Barcode\"

Abstract

Studies on the diversity of macroalgae from mangroves in Brazil have been based only on morphological approaches, in which characters used are unstable and uninformative for the species identification and delimitation. In this context, macroalgae of mangroves were investigated for the first time in the Brazilian coast using a molecular approach, having as target of our study the mangrove of the Barnabé Island, Santos, São Paulo.DNA Barcode markers UPA and COI-5P were used, besides the rbcL, largely used for phylogenetic inferences, and also SSU rDNA. In addition to these, the ITS and tufA markers were used exclusively for the green algae, the latter unsuccessfully. Fifteen species were recorded for the studied area, ten Rhodophyta and five Chlorophyta. Of these, two are new records for the State of São Paulo, Caloglossa apomeiotica e Boodleopsis vaucherioidea. Of the four species of the genus Bostrychia identified in this study: "Bostrychia calliptera ", B. montagnei, B. moritziana and B. radicans, only B. montagnei proved to be a molecular and morphologically well-defined species. The other species formed complexes with different molecular lineages. For B. radicans and B. moritziana, the analyses showed three and two molecular lineages, respectively, of the seven identified for the B. radicans/B. moritziana complex in the literature. The taxon identified as "B. calliptera" showed high molecular divergence with sequences of B.calliptera from Brazil, presenting morphology "B. pinnata", a taxon currently reduced to a synonym of B. calliptera. Caloglossa species, except C. ogasawaraensis, are difficult to identify due to the subtle morphological characters considered of diagnostic value, and their considerable phenotypic plasticity. Caloglossa apomeiotica, C. confusa and C. leprieurii were identified primarily by the use of molecular markers. Caloglossa apomeiotica can be segregated from the others by the presence of bisporangia, which makes unreliable morphological identification when collected infertile thalli, while C. confusa has strongly constricted thallus nodes. The molecular data obtained for Catenella caespitosa from SSU sequences suggest that the citations of this species for the Brazilian coast may be misleading since they have high intraspecific divergence with C. caespitosa from database. Due to the lack of sequences from the type locality, sequences of DNA barcode markers, and a major molecular sampling of Catenella species in databases, became impossible to reach a conclusive result. The obtaining of sequences for green algae was extremely problematic, making impracticable a broader comparison between the collected species. Of the two collected species of Boodleopsis, only two partial sequences of rbcL were obtained for B. vaucherioidea and none for B.pusilla. The comparison with the unique sequence of Boodleopsis deposited in databases, a partial rbcL sequence of B. pusilla, revealed low molecular divergence with our sequences of B. vaucherioidea. Besides the need to obtain complete seque...

O efeito da zonação e sazonalidade na composição da fauna associada à comunidade Bostrychietum em costões do litoral norte do Estado de São Paulo

“…As macroalgas presentes na amostra foram separadas e identificadas em nível de gênero e espécie de acordo com Joly (1954), Taylor (1960), Creed et al (2010), Nassar (2012), Sena (2016) e Santos (2016). As espécies de Bostrychia foram identificadas utilizando caracteres morfológicos como o tipo de hapteron, padrão de ramificação, número de ordem de ramos, presença ou ausência de corticação nos eixos principais, forma dos ápices, forma e tamanho dos estiquídios (ramos laterais especializados que produzem esporos) (Joly, 1954;Taylor, 1960;King & Puttock, 1989;Zuccarello & West, 2008;Fontes, 2012).…”