Morphology and molecular phylogeny of a new PST-producing dinoflagellate species: Alexandrium fragae sp. nov. (Gonyaulacales, dinophyceae).

The genus Alexandrium comprises some of the most potentially toxic marine algae. A new toxic species of Alexandrium, A. fragae sp. nov., was found in Guanabara Bay, Rio de Janeiro, southern Brazil. The new species produces GTX2&3 and STX. The cell morphology of A. fragae resembles A. minutum in many characters, including the small size; the rounded-elliptical shape; and the shapes of the apical pore complex (APC), first apical plate (1'), sixth precingular plate (6″), and anterior and posterior sulcal plates (s.a. and s.p.). The main diagnostic characters of A. fragae are the ornamentation pattern, smooth epitheca and reticulated hypotheca, all of which were present in both natural populations and cultures. Phylogenies inferred from the ITS, LSU, and SSU rDNA of A. fragae showed that A. fragae clustered in a well-supported clade, distinct from other Alexandrium species. Morphology and molecular analyses based on ITS and LSU rDNA indicated that A. fragae strains and Alexandrium sp. from Japan (D163C5, D164C6) are a single species. Our findings suggest that the Alexandrium morphotype with a smooth epitheca and reticulated hypotheca, previously identified as A. minutum in different geographic regions, may corresponds to A. fragae.

First report of vampyrellid predator-prey dynamics in a marine system.

We report for the first time the in situ dynamics of a vampyrellid in a marine system. A high sampling frequency (twice-weekly) was applied in a tropical eutrophic lagoon (Rio de Janeiro, Brazil) for 5 years (2012-2016). The vampyrellid Hyalodiscus sp. specifically fed on the diatom Chaetoceros minimus during a short time window (~3 months), although the prey was intermittently detected as the dominant phytoplanktonic species over a longer period (~1 year). A classic Lotka-Volterra predator-prey dynamic was observed between the two partners, with a significant modification of the short-term oscillations of the prey. Specific abiotic preferences (i.e., relatively low temperature, intermediate salinity, and stratified conditions) associated with prey availability seemed to define this narrow temporal window of occurrence. Our results suggest that vampyrellids can be ecologically relevant in marine pelagic systems, with their impact on planktonic dynamics strongly depending on complex interactions between both biotic and abiotic factors.

Metagenomic Analysis of Cyanobacteria in an Oligotrophic Tropical Estuary, South Atlantic.

This study assessed the species composition, distribution, and functional profiles of cyanobacteria in Camamu Bay, a tropical oligotrophic estuarine system on the northeast coast of Brazil, using shotgun metagenomic sequencing. Surface-water samples were evaluated in two different rainfall periods (rainy and dry seasons), at nine stations in the three hydrodynamic regions of the bay. At a fixed sampling station, on each season, samples were taken over a tidal cycle at 3-h intervals over 12 h. A total of 219 cyanobacterial taxa were identified, demonstrating a diverse community of freshwater, euryhaline, and marine cyanobacteria. The genera of greater relative abundance, Synechococcus and Prochlorococcus, corresponded to the picoplankton fraction. Although Camamu Bay has conspicuous marine characteristics, the contribution of freshwater during the rainy season caused variation in cyanobacteria community, with an increase in species richness. Due the high prevalence of Synechococcus (90% of the sequences), the functional analysis revealed only minor differences in gene content between the dry and rainy seasons. In both rainy and dry seasons, an increase in Prochlorococcus relative abundance occurred during high tide, demonstrating the tidal influence in the bay. The environmental characteristics of the bay provide niche conditions for a wide variety of cyanobacteria, including freshwater, euryhaline, and marine strains.

Morphology and phylogeny of Prorocentrum caipirignum sp. nov. (Dinophyceae), a new tropical toxic benthic dinoflagellate.

A new species of toxic benthic dinoflagellate is described based on laboratory cultures isolated from two locations from Brazil, Rio de Janeiro and Bahia. The morphology was studied with SEM and LM. Cells are elliptical in right thecal view and flat. They are 37-44µm long and 29-36µm wide. The right thecal plate has a V shaped indentation where six platelets can be identified. The thecal surface of both thecal plates is smooth and has round or kidney shaped and uniformly distributed pores except in the central area of the cell, and a line of marginal pores. Some cells present an elongated depression on the central area of the apical part of the right thecal plate. Prorocentrum caipirignum is similar to Prorocentrum lima in its morphology, but can be differentiated by the general cell shape, being elliptical while P. lima is ovoid. In the phylogenetic trees based on ITS and LSU rDNA sequences, the P. caipirignum clade appears close to the clades of P. lima and Prorocentrum hoffmannianum. The Brazilian strains of P. caipirignum formed a clade with strains from Cuba, Hainan Island and Malaysia and it is therefore likely that this new species has a broad tropical distribution. Prorocentrum caipirignum is a toxic species that produces okadaic acid and the fast acting toxin prorocentrolide.

Toxin production, growth kinetics and molecular characterization of Ostreopsis cf. ovata isolated from Todos os Santos Bay, tropical southwestern Atlantic.

The toxin profile and hemolytic activity of a strain of Ostreopsis cf. ovata (UFBA013) isolated from Todos os Santos Bay (northeastern Brazil) were evaluated under different levels of N and P. Phylogenetic analyses based on ITS rDNA region (ITS1-5.8S-ITS2) placed UFBA013 within the Atlantic/Mediterranean/Pacific clade of O. cf. ovata. Growth experiments were conducted in f/2 medium modified by adding N and P (P: 0-36 µM; N: 0-882 µM). The growth kinetics was adequately described by logistic equations. The best growth (highest Gm) was recorded under levels of N/P = 0/18, 129/5 and 441/36, while one of the lowest Gm was obtained under P-depletion. The maximum and specific maximum growth rates (as vm; cells mL-1 d-1 and µm; d-1) were achieved with N limitation (N/P = 441/36) and P-limitation/depletion (753/5.3 and 441/0) and are the highest values reported in the literature, most similar to isolates from Pacific and Mediterranean areas. The control experiment (N/P = 441/18) also yielded similar values to those from some Mediterranean isolates, but higher than formerly reported for Brazilian isolates. In all conditions assayed, no palytoxin (PLTX) was detected. The ovatoxins (OVTXs) a, b, c, d and e did not show significant differences in cell quota between exponential and stationary phases. A significant relationship was detected between OVTXs concentration and hemolytic activity.

Prorocentrum lima from the South Atlantic: Morphological, molecular and toxicological characterization.

Morphological descriptions using light and scanning electron microscopy and molecular characterization of two Prorocentrum lima strains (UNR-01 and UNR-09) isolated from Armação dos Búzios, Rio de Janeiro, Brazil are provided. Okadaic acid (OA), dinophysistoxin-1 (DTX1) and DTX2 production by strain UNR-01 was investigated using liquid chromatography with mass spectrometry. Toxins were extracted from heat-treated (boiled) and non-boiled cell pellets to obtain respective quantities of free and total OA and DTX1. Growth parameters (growth rate and mean generation time) were determined for strain UNR-01. Prorocentrum lima cells were oblong-to-ovate in shape, broad in the middle region, and narrow at the anterior end. The periflagellar area was triangular, set into a V-shaped depression and was composed of eight periflagellar platelets of different sizes. The morphology fits well the characterization of the species isolated from elsewhere. Phylogenetic analysis based on internal transcribed spacer - ITS - and D1-D3 large subunit - LSU - of ribosomal RNA gene sequences revealed that both strains were identical and closely related to P. lima isolates from the Caribbean Sea and USA. The growth rate of strain UNR-01 was 0.24divday-1. OA concentrations were on average 15.2 and 38.5pg[OA]cell-1 for heat-treated and non-treated cells respectively, while DTX1 mean concentration was 0.5pg[DTX1]cell-1 for both heat-treated and non-treated cells. DTX2 was not detected. To date, these are the first strains of P. lima from the south Atlantic that have been characterized.

Typification and taxonomic status re-evaluation of 15 taxon names within the species complex Cymbellaaffinis/tumidula/turgidula (Cymbellaceae, Bacillariophyta).

Specimens belonging to the Cymbellaaffinis / Cymbellatumidula / Cymbellaturgidula species complex have many taxonomic problems, due to their high morphological variability and lack of type designations. Fifteen taxon names of this complex, distributed in five species, were re-evaluated concerning their taxonomic status, and lectotypified based on original material. In addition to light microscopy, some material was analyzed by electron microscopy. Four new combinations are proposed in order to reposition infraspecific taxa.

Diatoms from Brazil: the taxa recorded by Christian Gottfried Ehrenberg.

The flora of diatoms from Brazil has been studied by several authors from the beginning of the 19(th) up to now. Some of the old lists and descriptions are unknown or have been ignored by Brazilian researchers and the situation of the names cited was not assessed. Here we compiled a list of 101 taxa of diatoms from Brazil registered by Christian Gottfried Ehrenberg during the 19(th) century. We checked the current nomenclatural status of those taxa and lectotypified species from Brazil described by this author. For this, we accessed the Ehrenberg collection in the Museum für Naturkunde, Berlin, Germany, where 11 samples from Brazil studied by Ehrenberg are housed and published in different papers. Using these samples, we found 101 taxa (specific and infraspecific) published by Ehrenberg from Brazil. Five species (Eunotia bidens Ehrenb., Eunotia depressa Ehrenb., Eunotia elephas Ehrenb., Pinnularia microstauron Ehrenb., and Terpsinoe brasiliensis Ehrenb.) were new descriptions and were lectotypified here. The other species cited for Brazil were described initially from other places. However, 23 names were invalid and one illegitimate.

Checklist das Cryptophyceae do estado de São Paulo, Brasil / Checklist of Cryptophyceae from São Paulo State, Brazil

Usando como base de informações a monografia sobre o grupo publicada pelo projeto Flora Ficológica do Estado de São Paulo (Programa BIOTA), o acervo depositado no Herbário Científico do Estado de São Paulo "Maria Eneyda P. Kauffmann Fidalgo" (SP), a Lista de Espécies da Flora do Brasil e artigos científicos, dissertações e teses (com descrições e ilustrações) temos: nove gêneros e 39 espécies de criptoficeas, sendo 16 espécies exclusivas para o Estado de São Paulo, todas registradas em ambientes de água doce. A carência de especialistas no Estado de São Paulo e no Brasil, além de problemas de estratégia amostral, necessidade de uso da microscopia eletrônica e ausência de estudos de biologia molecular, são fatores que devem ter subestimado o conhecimento taxonômico de Cryptophyceae no Estado.

Based on the information provided by the monograph on the group published by the project Phycology Flora of São Paulo (BIOTA), the collection deposited in the Scientific Herbarium "Mary P. Eneyda Kauffmann Fidalgo " of the State of São Paulo, the List of Endangered Species of the Flora of Brazil and scientific papers, dissertations and theses (with descriptions and illustrations), there are nine genera and 39 species of cryptophytes, 16 of which are unique species to the State of São Paulo, all recorded in freshwater environments. The lack of specialists in the State of São Paulo and Brazil as well as problems in the sampling strategy, the necessary use of electronic microscopy and the absence of molecular biology studies are factors that must have underestimated the taxonomic knowledge of Cryptophyceae in the state.

Freshwater Raphidophyceae from the State of Rio de Janeiro, Southeast Brazil / Raphidophyceae de água doce do Estado do Rio de Janeiro, Sudeste do Brasil

This paper presents a floristic survey of Raphidophyceae (Heterokontophyta) found in three freshwater environments in the municipality of Rio de Janeiro, based on samples collected bimonthly from September 1988 to August 1991. A total of 117 samples were collected, and eight of these contained cells of raphidophytes. Altogether five raphidophyte species, representing the genera Gonyostomum (2), Merotrichia (1), and Vacuolaria (2) were identified. Four species are new records for the State of Rio de Janeiro (G. semen, G. depressum, M. bacillata, V. virescens var. virescens), and one is reported for the first time in Brazil (V. viridis). Gonyostomum semen and V. virescens var. virescens are the most widespread taxa in the area, found in 50 and 25 percent of the total of samples, respectively. With the exception of M. bacillata and V. viridis, most of the taxa occurred in a natural oligotrophic lake with acidic waters, in accordance with the preference of raphidophytes for low pH. This study clearly supports the need for more extensive taxonomic surveys on these raphidophytes, based on field and cultured samples and under light and electron microscopy, to confirm the taxonomic identity of the previously reported species and to expand the knowledge of the taxa in Brazil. The bloom of G. semen reported here, together with its gradual dominance in the aquatic systems in the State of Rio de Janeiro seems to conform to the recent spread of this species into new areas, and can be viewed as a potential risk for environmental health.

Este trabalho apresenta o inventário florístico de Raphidophyceae (Heterokontophyta) encontradas em três corpos d'água doce no Município do Rio de Janeiro. Cento e dezessete amostras foram coletadas bimensalmente entre setembro de 1988 a agosto de 1988, das quais oito com representantes de rafidófitas distribuídas em duas espécies de Gonyostomum, uma de Merotrichia e duas de Vacuolaria. Quatro espécies constituem novos registros de ocorrência para o Estado do Rio de Janeiro (G. semen, G. depressum, M. bacillata, V. virescens var. virescens) e uma é citada pela primeira vez para o Brasil (V. viridis). Gonyostomum semen e V. virescens var. virescens foram os táxons com maior distribuição na área de estudo totalizando 50 e 25 por cento do total das amostras, respectivamente. Exceto M. bacillata e V. viridis, as demais espécies ocorreram principalmente em lago natural oligotrófico com águas ácidas reforçando a preferência do grupo a baixos valores de pH. Este estudo suporta a necessidade de realizar inventários taxonômicos mais extensivos sobre rafidófitas a partir de amostras de campo e de cultura com base em microscopia ótica e eletrônica para confirmar a identidade taxonômica das espécies já registradas e ampliar o conhecimento do grupo no Brasil. A floração de G. semen registrada neste trabalho aliada a sua gradual dominância em ambientes aquáticos no Estado do Rio de Janeiro parece suportar a recente expansão dessa espécie em novas áreas e pode ser visto como um potencial risco a saúde do meio ambiente.

[Regimento proueytoso contra ha pestenença. Glossary]. / Regimento proueytoso contra ha pestenença. Glossário.

The main goal of the following glossary is to work as a support to the reading of Regimento proueytoso contra ha pestenença. For this reason it includes every word in the text. However, since it may interest one concerned with the history of Portuguese, the glossary was supplied with additional information on orthography and on the original form of the words.