ABSTRACT The green algal genus Bryopsis has simple morphology and high phenotypic plasticity, making it difficult to identify its species based on morphological characteristics alone. This study evaluated the diversity of Bryopsis in northeastern Brazil (the State of Pernambuco), based on morphological and molecular data using the markers tufA and rbcL. Molecular analyses were incongruent with morphology, demonstrating the existence of cryptic and polymorphic species in the genus. Of the four taxa cited for the area based only on morphological data (Bryopsis corymbosa, B. pennata, B. plumosa, Bryopsis sp.), only B. pennata was recorded. Typical specimens of B. pennata and B. plumosa were grouped with low genetic divergence, 0-0.21 % for tufA and no divergence for rbcL, indicating that B. pennata is an extremely plastic species that includes specimens with morphotype B. “plumosa”. Bryopsis pennata var. secunda is cited for the first time for northeastern Brazil, with divergence from the typical variety of 0.96-1.57 % for tufA and 0.4 % for rbcL. This study showed that broader sampling of Bryopsis is necessary in order to confirm the taxonomic status of the species referenced for Brazil, whose phenotypic plasticity may cause overestimation of diversity or reveal cryptic species.

The diversity of algal banks composed of species out the genera Gracilaria Greville and Hypnea J.V. Lamouroux have been impacted by commercial exploitation and coastal eutrophication. The present study sought to construct dynamic models based on algal physiology to simulate seasonal variations in the biomasses of Gracilaria and Hypnea an intertidal reef at Piedade Beach in Jaboatão dos Guararapes, Pernambuco State, Brazil. Five 20 × 20 cm plots in a reef pool on a midlittoral reef platform were randomly sampled during April, June, August, October, and December/2009 and in January and March/2010. Water temperature, pH, irradiance, oxygen and salinity levels as well as the concentrations of ammonia, nitrate and phosphate were measured at the sampling site. Forcing functions were employed in the model to represent abiotic factors, and algal decay was simulated with a dispersal function. Algal growth was modeled using a logistic function and was found to be sensitive to temperature and salinity. Maximum absorption rates of ammonia and phosphate were higher in Hypnea than in Gracilaria, indicating that the former takes up nutrients more efficiently at higher concentrations. Gracilaria biomass peaked at approximately 120 g (dry weight m-2) in March/2010 and was significantly lower in August/2009; Hypnea biomasses, on the other hand, did not show any significant variations among the different months, indicating that resource competition may influence the productivity of these algae.

We surveyed the aquatic macrophytes in reservoirs in Camocim de São Félix in the Agreste zone of Pernambuco State, Brazil. Plants were collected on a bimonthly schedule from November/2008 to May/2009 in four reservoirs, and 33 taxa distributed among 23 families were encountered. The family Cyperaceae had the greatest number of species, followed by Lemnaceae. The predominant biologic form was emergent (33.3%) reflecting the extensive shorelines around the reservoirs analyzed.

Este trabalho apresenta o levantamento florístico e alguns aspectos ecológicos das algas vermelhas do Arquipélago de São Pedro e São Paulo (00º56'N; 29º22'W - 00º 55'N; 29º 20'W). O material foi coletado durante as marés baixas em seis estações, nas zonas entre-marés e infralitoral no mês de outubro de 2003 (estação seca) e abril de 2005 (estação chuvosa). Foram registradas 24 espécies, distribuídas entre as ordens Bonnemaisoniales (uma espécie), Ceramiales (12 espécies), Corallinales (seis espécies), Erythropeltidales (uma espécie), Gelidiales (uma espécie), Rhodymeniales (duas espécies) e Stylonematales (uma espécie). Foram feitos 15 novos registros de rodofíceas à flora do Arquipélago e quatro novas adições para as ilhas oceânicas brasileiras: Ceramium brevizonatum var. caraibicum H. E. Petersen & Börgesen, Ceramium tenerrimum (G. Martens) Okamura, Jania prolifera A. B. Joly e Stylonema alsidii (Zanardini) K. M. Drew. Foram registradas algas vermelhas em apenas três estações. A maior riqueza de táxons (16 taxa) ocorreu na Estação 01 (Enseada) e no período chuvoso (23 taxa). A similaridade florística, com base no índice de Sørensen, em relação à profundidade, variou de 0 a 0.66%.

This paper presents a floristic survey of the red algae and some ecological aspects of the São Pedro and São Paulo Archipelago (00º56'N; 29º22'W - 00º55'N; 29º 20'W). Collections were carried out during low tide in six stations located in the intertidal and infralittoral zones, in October 2003 (dry season) and April 2005 (rainy season). It was registered 24 infrageneric taxa distributed among the orders Bonnemaisoniales (1 specie), Ceramiales (12 species), Corallinales (6 species), Erythropeltidales (1 specie), Gelidiales (1 specie), Rhodymeniales (2 species) and Stylonematales (1 specie). Fifteen taxa are new records to the Archipelago flora. It was also registered four new records to the Brazilian oceanic islands: Ceramium brevizonatum var. caraibicum H. E. Petersen & Börgesen, Ceramium tenerrimum (G. Martens) Okamura, Jania prolifera A. B. Joly and Stylonema alsidii (Zanardini) K. M. Drew. The red algae were registered only in three stations. The highest specific diversity (16) occurred to Station 01 (Enseada) and to the rainy season (23 species). The Søresen floristic similarity in relation to depth varied from 0 to 0.66%.

A seqüência completa do SSU rDNA foi obtida para 10 indivíduos de Cladophora vagabunda coletadas ao longo da costa do Brasil. Uma seqüência parcial do SSU rDNA (1634 bp) foi obtida para C. rupestris (L.) Kütz. As árvores filogenéticas indicam que Cladophora é parafilético, mas a seção Glomeratae sensu lato compreendendo C. vagabunda do Brasil, Japão e França, C. albida (Nees) Kütz., C. sericea (Hudson) Kütz. e C. glomerata (L.) Kütz., é monofilética. Dentro deste grupo, C. vagabunda é parafilética. A identidade da seqüência para o SSU rDNA variou de 98,9% à 100% para C. vagabunda brasileira e de 98,3% a 99,7% quando comparados os indivíduos brasileiros aos da França e do Japão. A identidade da seqüência entre C. vagabunda brasileira e as duas outras espécies (C. albida e C. sericea) variou entre 98,0% e 98,6%. A filogenia do SSU rDNA suporta parcialmente as caracteristícas morfológicas apresentadas pelas populações brasileiras de C. vagabunda. Por outro lado, C. rupestris do Brasil não se agrupou a C. rupestris da França, as duas seqüências apresentaram somente 96,9% de identidade. A inclusão de seqüências de indivíduos do Brasil reforçam a necessidade de uma revisão taxonômica para o gênero Cladophora e para o complexo C. vagabunda.

The complete SSU rDNA was sequenced for 10 individuals of Cladophora vagabunda collected along the coast of Brazil. For C. rupestris (L.) Kütz. a partial SSU rDNA sequence (1634 bp) was obtained. Phylogenetic trees indicate that Cladophora is paraphyletic, but the section Glomeratae sensu lato including C. vagabunda from Brazil, Japan and France, C. albida (Nees) Kütz., C. sericea (Hudson) Kütz., and C. glomerata (L.) Kütz. is monophyletic. Within this group C. vagabunda is paraphyletic. The sequence identity for the SSU rDNA varied from 98.9% to 100% for the Brazilian C. vagabunda, and from 98.3% to 99.7% comparing the Brazilian individuals to the ones from France and Japan. Sequence identity of the Brazilian C. vagabunda to C. albida and C. sericea vary from 98.0% to 98.6%. The SSU rDNA phylogeny support partially the morphological characteristics presented by Brazilian populations of C. vagabunda. On the other hand, C. rupestris from Brazil does not group with C. rupestris from France, both sequences presenting only 96.9% of identity. The inclusion of sequences of individuals from Brazil reinforces the need of taxonomical revision for the genus Cladophora and for the complex C. vagabunda.

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%).

Este trabalho identifica e fornece a distribuição do gênero Caulerpa na costa de Pernambuco (07º30' S e 09º00' W) e no Arquipélago de Fernando de Noronha (03º51' S e 32º25' W). As coletas foram realizadas em 32 praias da costa de Pernambuco no período entre abril/2004 a novembro/2005, na região entre-marés. Em Fernando de Noronha as coletas foram feitas em junho/2006, na região entre marés e no infralitoral (10, 15 e 21 m de profundidade), em oito praias. Foram, também, analisadas as exsicatas de Caulerpa depositadas no Herbário Professor Vasconcelos Sobrinho (PEUFR) da Universidade Federal Rural de Pernambuco. Os resultados mostram que o gênero Caulerpa está representado na costa de Pernambuco, por 19 táxons infragenéricos. Algumas espécies apresentaram distribuição restrita como C. kempfii Joly & Pereira, C. lanuginosa J. Agardh e C. serrulata (Forssk.) J. Agardh. Para o Arquipélago de Fernando de Noronha foram registrados três táxons infragenéricos.

This paper analyzes the taxonomy and distribution of the genus Caulerpa on the coast of Pernambuco (07º30'S; 09º00'W) and in the Fernando de Noronha Archipelago (03º51'S; 32º25'W). Sampling was carried out on the coast of Pernambuco from April/2004 to November/2005, in the intertidal zone of 32 beaches. On Fernando de Noronha collections were made in June/2006 in the intertidal and infralittoral (10, 15 and 21m depth) regions of eight beaches. Exsiccata of Caulerpa from the Professor Vasconcelos Sobrinho Herbarium (PEUFR) were also examined. The results showed that the genus Caulerpa is represented on the coast of Pernambuco state by 19 infrageneric taxa. Some species had restricted distributions such as C. kempfii Joly & Pereira, C. lanuginosa J. Agardh and C. serrulata (Forssk.) J. Agardh. Three infrageneric taxa were registered for the Fernando de Noronha Archipelago.