Currently, five genera are assigned to red seaweeds of the Laurencia complex worldwide: Chondrophycus, Laurencia s.s., Osmundea, Palisada and Yuzurua. The genera are segregated on the basis of morphological characters, especially the reproductive traits, and molecular sequences of the plastid-encoded gene rbcL. Four of the genera have been resolved as monophyletic, but not Laurencia s.s. In this study based on an rbcL gene phylogeny we show the presence of a sixth lineage within the Laurencia complex, viz., Laurencia marilzae plus two unidentified species of Laurencia from Brazil. The phylogenetic position of this group, combined with the high genetic divergence from Laurencia s.s. (8.2–11%), strongly support the establishment of a sixth genus for the complex, proposed here as Laurenciella gen. nov. This new taxon differs from Laurencia s.s. and from the other genera of the complex by molecular sequence data, but is indistinguishable from Laurencia s.s. by the usual morphological features.

Extreme temperature events are becoming more recurrent and are more frequent with major impacts on coastal ecosystems, which are additionally impacted by increasing urbanization, resulting in high nutrient load. So far little is known about cumulative and/or interactive effects of global and local stressors on species' performance. Here, we evaluated the single and combined effects of simulated heatwaves and eutrophication on the ecophysiology of Laurencia catarinensis in a bi-factorial mesocosm experiment. The algae were exposed for 30 d to three different temperatures (208C, 248C, 288C) and nutrient concentrations (low, intermediate, high) and their nutrient uptake rates, photosynthetic performance, growth rates, pigment and phenolic compound concentrations, as well as antioxidant capacity was determined and compared between treatments. Under low nutrient concentration, physiological performance and growth decreased with increasing temperatures. In contrast, they increased with higher nutrient availability and moderate temperature increase close to the summer average temperature, but largely declined upon exposure to higher temperature (288C). This decline seemed to be related to oxidative stress, as indicated by an increase of compounds with antioxidant properties (lutein, zeaxanthin, phenols). Our data show that all measured parameters were affected by temperature and nutrient availability, with an interactive effect between these two factors, indicating that increasing temperature will influence macroalgal performance, and even more dramatically in coastal systems that are highly impacted by urbanization. However, the direction of the response will be determined by nutrient availability and will also depend on the magnitude of the temperature increase, that is, whether it surpasses the thermal threshold of the species.Marine macroalgae are dominant and essential components of coastal ecosystems around the world (Gattuso et al. 1998;Harley et al. 2012) and are currently threatened by a multitude of stressors, such as those related to global climate change (Harley et al. 2006(Harley et al. , 2012, but also locally by increasing nutrient and sediment loading, the overfishing and spread of invasive species (Worm and Lotze 2006;Schmidt and Scheibling 2007). Current changes in seawater temperature, due to climatic change, predict for the end of this century a continuous warming of near-surface air temperature, on the order of 2-78C with regional, seasonal and diurnal

An updated synthesis of cyanobacteria and algae information is presented for Brazil aiming to refine the data gathered to date and evaluate the progress of the biodiversity knowledge about these organisms in the country since the publication of the Catálogo de Plantas e Fungos do Brasil. The results of 2015 showed an increase of 1,250 species (35.7%) when compared to 2010, reaching a total of 4,747 species. The most diverse classes in species number were the Bacillariophyceae, Conjugatophyceae, Florideophyceae, Cyanophyceae, Dinophyceae and Euglenophyceae. Bacillariophyceae and Cyanophyceae had the highest increase in species number in the five-year interval. The Southeast and South regions were the most diverse, however, the Northeast, with the states of Piauí and Sergipe, and the Central-west region, with Mato Grosso, Goiás and Distrito Federal, also stood out in the national algal biodiversity scenario. Despite the shortage of taxonomists and limited infrastructure, the results showed a significant improvement in the knowledge regarding the diversity of cyanobacteria and algae in the country during the study period, starting to even out regional geographical differences caused by subsampling. Key words: Biodiversity, phycology. ResumoApresenta-se uma síntese atualizada de informações sobre algas no Brasil objetivando refinar os dados reunidos até o presente, bem como avaliar os avanços sobre o conhecimento da diversidade de algas no país desde a publicação do Catálogo de Plantas e Fungos do Brasil. Os resultados de 2015 mostraram um acréscimo de 1.250 espécies (35.7%) a um total de 4.747 em relação a 2010. As classes mais diversas em número de espécies foram Bacillariophyceae, Conjugatophyceae, Florideophyceae, Cyanophyceae, Dinophyceae e Euglenophyceae. Bacillariophyceae e Cyanophyceae tiveram o maior acréscimo de espécies no intervalo de cinco anos. A região Sudeste e Sul foram as mais diversas, porém, as regiões Nordeste com os estados do Piauí e Sergipe e Centro-Oeste com os estados de Mato Grosso, Goiás e Distrito Federal destacaram--se no cenário da biodiversidade nacional. Apesar da escassez de taxonomistas e da infraestrutura limitada, os resultados obtidos evidenciaram um avanço significativo no conhecimento da diversidade de algas no país nesse período de cinco anos, iniciando uma mudança quanto as diferenças geográficas regionais. Palavras-chave: Biodiversidade, ficologia.

Morphological and molecular studies have been performed on Laurencia dendroidea derived from Brazil and the Canary Islands. This species possesses all of the characters that are typical of the genus Laurencia, including the production of the first pericentral cell underneath the basal cell of the trichoblast; the production of tetrasporangia from particular pericentral cells without the formation of additional fertile pericentral cells; spermatangial branches that are produced from one of two laterals on the suprabasal cell of the trichoblasts; and a procarp-bearing segment that possesses five pericentral cells. The phylogenetic position of L. dendroidea was inferred by analysing the chloroplast-encoded rbcL gene sequences of 51 taxa. Phylogenetic analyses revealed that the taxa previously identified and cited in Brazil as Laurencia filiformis, L. majuscula and L. obtusa and in the Canary Islands as L. majuscula all represent the same taxonomic entity and examination of type material allowed us to identify this entity as L. dendroidea, whose type locality is in Brazil. Laurencia obtusa from the Northern Atlantic is confirmed to represent a distinct species, which displays high genetic divergence with respect to western and eastern Atlantic samples.

Abstract:Two new chamigrane sesquiterpenes 1-2 and three known compounds 3-5 were isolated from a lipophilic extract of the red alga Laurencia dendroidea collected from the OPEN ACCESSMolecules 2014, 19 3182 Southeastern Brazilian coast. Dendroidone (1) and dendroidiol (2) were isolated from samples collected at Biscaia Inlet, Angra dos Reis, Rio de Janeiro and at Manguinhos Beach, Serra, Espírito Santo, respectively. Debromoelatol (3), obtusane (4) and (1S*,2S*,3S*,5S*,8S*,9S*)-2,3,5,9-tetramethyltricyclo[6.3.0.0 1.5 ]undecan-2-ol (5) were obtained from specimens collected at Vermelha Beach, Parati, Rio de Janeiro. The structures of new compounds were elucidated by extensive NMR ( 1 H-, 13 C-, COSY, HSQC, HMBC and NOESY) and high resolution mass spectrometry analysis. Additionally, the absolute configuration of compound 2 was assigned by X-ray analysis. Full spectroscopic data is described for the first time for compound 3. Anti-inflammatory and antimycobacterial activities of compounds 2-5 were evaluated. Compounds 3-5 inhibited the release of inflammatory mediator NO while TNF-α levels were only affected by 3. All compounds tested displayed moderate antimycobacterial action.

No abstract

Hypnea musciformis, a red macroalga widely distributed in tropical and subtropical coasts around the world, has great economic importance as a source of carrageenan for industrial production. In this work, the DNA barcode marker COI-5P and the plastid rbcL gene, in addition to morphological studies, were used to investigate this species on the coast of Brazil and compare it with specimens from other countries. A total of 128 sequences were obtained in this study for 100 specimens from Brazil and 15 specimens from other countries, including the type locality in Italy. The divergence between South American sequences and sequences from Italy for H. musciformis was significantly high for both markers, indicating that the specimens found on the Brazilian coast belong to a different species. Considering the data gathered from molecular markers and morphological analysis, the specimens previously identified morphologically as "H. musciformis", "Hypnea nigrescens", and "Hypnea valentiae" collected in Brazil were considered morphological variations of the new species described in this paper, named Hypnea pseudomusciformis Nauer, Cassano & M.C. Oliveira, sp. nov. The identification of specimens based only on morphological characteristics proved to be unsatisfactory for reasons that could be attributed to phenotypic plasticity in this species. Thus, the technique of DNA barcoding, especially with respect to the COI-5P marker, was essential for the identification and definition of species, revealing scenarios that would otherwise be ignored by using only morphological analysis.

Abstract:In Brazil, the Laurencia complex is represented by twenty taxa: Laurencia s.s. with twelve species, Palisada with four species (including Chondrophycus furcatus now that the proposal of its transference to Palisada is in process), and Osmundea and Yuzurua with two species each. The majority of the Brazilian species of the Laurencia complex have been phylogenetically analyzed by 54 rbcL sequences, including five other Rhodomelacean species as outgroups. The analysis showed that the Laurencia complex is monophyletic with high posterior probability value. The complex was separated into five clades, corresponding to the genera: Chondrophycus, Laurencia, Osmundea, Palisada, and Yuzurua. A bibliographical survey of the terpenoids produced by Brazilian species showed that only six species of Laurencia and five of Palisada (including C. furcatcus) have been submitted to chemical analysis with 48 terpenoids (47 sesquiterpenes and one triterpene) isolated. No diterpenes were found. Of the total, 23 sesquiterpenes belong to the bisabolane class and eighteen to the chamigrene type, whose biochemical precursor is bisabolane, two are derived from lauranes and four are triquinols. Despite the considerable number of known terpenes and their ecological and pharmacological importance, few experimental biological studies have been performed. In this review, only bioactivities related to human health were considered.