Resumen: La familia Asteraceae representa aproximadamente un 12% de las especies de plantas con flores en el mundo. Se estima que tienen un origen entre 50-70 millones de años y que han evolucionado rápidamente, lo que ha permitido que ocuparan diversos tipos de hábitats, incluso convirtiéndose en malezas de los humedales. Se dan a conocer las especies acuático-palustres de Paraguay, para lo cual se realizaron colectas botánicas y se revisaron especímenes depositados en diferentes herbarios. Se identificaron 32 especies que habitan los humedales, siete de ellas en ambientes lóticos, 27 en lénticos y 10 estrictamente acuáticas. La tribu mejor representada es Eupatorieae, seguida de Vernonieae. Solo una especie se reporta como endémica. Es aún escaso el conocimiento sobre la flora de los humedales, por lo que es necesario aumentar las colecciones en esos hábitats.

Summary: The Asteraceae family represents about 12% of the species of flowering plants in the world. It is estimated that they originated around 50-70 million years ago, have evolved quickly, and colonized various types of habitats, even becoming wetland weeds. The aquatic-palustrine species of Paraguay are disclosed, for which botanical collections were made and specimens deposited in different herbaria were reviewed. In total, 32 species inhabiting the wetlands were found, seven of them belong to lotic environments, 27 to lentic and 10 strictly aquatic. The best represented tribe is Eupatorieae, followed by Vernonieae. Only one species is reported as endemic. Knowledge about the flora of wetlands is still scarce, so it is necessary to increase the collections in these habitats.

ABSTRACT The crab-eating raccoon Procyon cancrivorus (Cuvier, 1798) is a species of the order Carnivora and family Procyonidae with a geographical distribution in Central and South America. Although crab-eating raccoons use scansorial locomotion, they also have aquatic habits, displaying greatly developed skills when handling their food. This species can frequently be found in wildlife care centers due to injuries caused by domestic dogs, humans, and car collisions. Having knowledge of the species’ gross anatomy and anatomical bases is imperative to perform the most appropriate medical and surgical procedures. Thus, the objective of this investigation was to analyze the interspecific and intraspecific differences of the craniolateral forearm muscles of Procyon cancrivorus. Gross dissections were performed in four specimens describing the origin, insertion, shape, innervation, and arterial supply of the craniolateral forearm muscles. There is a constant and well development of brachioradialis muscle comparatively to that described in strictly cursorial species; the extensor carpi radialis muscle has two bellies that are fused proximally; the extensor digitorum communis muscle can also extend the tendon to the digit I as an anatomical variant, and the extensor digiti I and II muscle also extends the tendon to digit III. All are innervated by the deep branch of the radial nerve, and their arterial supply is mainly by the radial collateral, cubital transverse, and cranial interosseous arteries. The anatomical characteristics observed in this study complement the previous descriptions for Procyon cancrivorus, and the anatomical variants found in this species can also be in other carnivorans. Thus, the intraspecific anatomical variations of the digital extensor muscles in P. cancrivorus are phylogenetic traits that can occur as a common pattern or as anatomical variants in other species of the order Carnivora.

RESUMEN. El mapache cangrejero Procyon cancrivorus (Cuvier, 1798) es una especie del orden Carnivora y familia Procyonidae con distribución geográfica en América Central y del Sur. Esta especie tiene hábitos arbóreos y acuáticos. Tiene una alta frecuencia en los centros de rehabilitación de fauna silvestre debido a las lesiones causadas por perros, humanos y colisiones de automóviles, por esto, tener conocimiento de la anatomía macroscópica de la especie es imprescindible para realizar los procedimientos médicos y quirúrgicos más adecuados. Por lo tanto, el objetivo de esta investigación fue analizar las diferencias inter e intraespecíficas de los músculos cráneo-laterales del antebrazo de Procyon cancrivorus. Se realizaron disecciones macroscópicas en cuatro especímenes donde se describió el origen, inserción, forma, inervación y la irrigación arterial de la musculatura cráneo-lateral del antebrazo. Entre los principales hallazgos se pueden mencionar: el músculo braquiorradial es constante y bien desarrollado comparativamente a lo descrito en especies estrictamente cursoriales; el músculo extensor radial del carpo presenta dos vientres fusionados proximalmente; el músculo extensor común de los dedos también puede formar un tendón al dedo I como una variante anatómica, y el músculo extensor de los dedos I y II también extiende un tendón al dedo III. Todos están inervados por el ramo profundo del nervio radial y su irrigación arterial es principalmente por las arterias colateral radial, transversa cubital e interósea craneal. Las características anatómicas encontradas en este estudio complementan las descripciones anteriores para Procyon cancrivorus, y las variantes anatómicas encontradas en esta especie también pueden encontrarse en otros carnívoros. Así, las variaciones anatómicas intraespecíficas de los músculos extensores digitales en P. cancrivorus son rasgos filogenéticos que se puede presentar en el patrón común o como variante anatómica en otras especies del orden Carnivora.

Resumo Atualizamos o primeiro checklist de macrófitas aquáticas do Nordeste do Brasil (Primeira Flora), que incluiu dados coletados até 2010, com uma nova lista de espécies baseada em dados de trabalhos publicados entre 2011 e 2017 (Nova Flora). Juntas, estas listagens registram 637 espécies de 89 famílias, com ênfase em espécies estritamente anfíbias ou emergentes, com 392 e 115 espécies, respectivamente. Encontramos diferenças na riqueza observada entre a Nova Flora e Primeira Flora, com aumento de 106 espécies na Nova Flora. A curva de rarefação mostrou que é necessário um aumento considerável no esforço de coleta para que possamos determinar a flora aquática da região estudada. A partir dos dados compilados, sugerimos novas perspectivas para inventários florísticos de macrófitas aquáticas, destacando a priorização de áreas mal estudadas, a exploração de informações ecológicas das espécies (e.g., endemismo, raridade, ameaça de extinção ou potencial invasivo), e a promoção de projetos em escala regional.

Abstract We updated the first checklist of aquatic macrophytes from Northeast Brazil (First Flora), which included data collected up to 2010, with a new checklist based on data from works published between 2011 and 2017 (New Flora). Together, these checklists record 637 species of 89 families, with an emphasis on strictly amphibious or emergent species, with 392 and 115 species, respectively. We found differences in observed richness between New Flora and First Flora, with an increase of 106 species in the New Flora. The rarefaction curve shows that a considerable increase in collection effort is necessary to determine the aquatic flora of the studied region. From the compiled data, we suggest new perspectives for floristic inventories of aquatic macrophytes, highlighting the prioritization of poorly studied areas; the exploration of ecological information of the species (e.g., endemism, rarity, threat of extinction or invasive potential); and the promotion of projects on a regional scale.

El propósito de este artículo es analizar, desde una mirada crítica, el riesgo a que se ven expuestas ciertas especies de silúridos, sometidas a procesos de hibridación por razones estrictamente comerciales, incluyendo los efectos sobre el hábitat, la competencia y la erosión genética. Es fácil comprender que dichos procedimientos tendrán en el futuro serios efectos sobre los recursos hidrobiológicos, los servicios ecosistémicos y la seguridad alimentaria, los cuales sólo pueden ser medidos a través del tiempo y no de forma inmediata.

The purpose of this article was to analyze, from a critical perspective, the risk that would be exposed some silurid species in captivity, subjected to hybridization processes for strictly commercial reasons, including habitat effects, competition and genetic erosion. It is easy to understand that these procedures will be in the future effects on aquatic resources, ecosystem services and food security, which can only be measured over time and not immediately.

O objetivo deste artigo foi analisar, a partir de uma perspectiva crítica, o risco ao qual seriam expostas algumas espécies de silúridos em cativeiro, sujeitos a processos de hibridação por razões exclusivamente comerciais, incluindo os efeitos sobre o habitat, a competição e a erosão genética. É fácil compreender que esses procedimentos terão, no futuro, efeitos sobre os recursos hidrobiológicos, os serviços ecossistêmicos e a segurança alimentar, os quais somente podem ser medidos ao longo do tempo e não de maneira imediata.

La tribu Berosini (Coleoptera: Hydrophilidae) está representada en América del Sur por los géneros Berosus Leach, Hemiosus Sharp y Derallus Sharp. Se presentan datos de material nuevo y de publicaciones precedentes y se propone una clasificación de los tipos de distribuciones. Pocas especies son estrictamente neotropicales. La mayoría de ellas están asociadas con una o más de las grandes cuencas fluviales (Paraguay-Paraná-Plata, Amazonas, Orinoco, Saõ Francisco y Desaguadero-Colorado-Negro), con influencia latitudinal en el Paraná-Plata. Las especies de Berosus y Derallus se distribuyen principalmente a lo largo de los ríos, las de Hemiosus se localizan sobre sustratos arenosos o (raramente) de grava, con influencia del origen de los sedimentos (andinos, macizo de Brasilia, etc).

The tribe Berosini (Coleoptera: Hydrophilidae) is represented in South America by the genera Berosus Leach, Hemiosus Sharp and Derallus Sharp. Distributional data from new material and from previous publications are given and a classification of the type of distribution is proposed. Few species are strictly Neotropical. Most species are associated with one or more of the main river systems (Paraguay-Paraná-Plata, Amazonas, Orinoco, Saõ Francisco and Desaguadero-Colorado-Negro), with latitudinal influence in the Paraná-Plata. Species of Berosus and Derallus are mostly distributed along the rivers, those of Hemiosus are located on sandy or (rarely) gravelly substrates, with influence of the origin of sediments (Andean, Brasilia shield, etc).

The Mid-Atlantic Ridge (MAR) divides the Atlantic Ocean longitudinally into two halves, each with a series of major basins delimited by secondary, more or less transverse ridges. Recent biological investigations in this area were carried out within the framework of the international project Mar-Eco (Patterns and Processes of the Ecosystems of the Mid-Atlantic Ridge). In 2009 (from October, 25 to November, 29) 12 benthic sampling events were conducted on the R/V Akademik Ioffe, during the first oceanographic cruise of South Atlantic Mar-Eco. As a result we report some rare Oplophoridae species collected during the cruise. This family includes 73 species occurring strictly on the meso- and bathypelagic zones of the oceans. Five Oplophoridae species were sampled: Acanthephyra acanthitelsonis Bate, 1888; A. quadrispinosa Kemp, 1939; Heterogenys monnioti Crosnier, 1987; Hymenodora glacialis (Buchholz, 1874) and Kemphyra corallina (A. Milne-Edwards, 1883). Among these, H. monnioti and K. corallina are considered extremely rare, both with very few records. Of the sampled species, only A. quadrispinosa and H. glacialis were previously recorded to southwestern Atlantic, so the Oplophoridae fauna of the South MAR seems more related with the fauna from the eastern Atlantic and Indian oceans.

La Cordillera Meso-Atlántica (CMA) divide el Océano Atlántico en dos partes, cada una con varias cuencas delimitadas por cadenas de montañas transversales. Recientemente se han efectuado investigaciones biológicas en esta región en el marco del proyecto internacional Mar-Eco (Patterns and Processes of the Ecosystems of the Mid-Atlantic Ridge). Entre octubre y noviembre de 2009 se obtuvo 12 muestras bentónicas durante el primer crucero oceanográfico del Mar-Eco del Atlántico Sur. Durante este crucero se encontraron algunas especies raras de la familia Oplophoridae. Esta familia incluye 73 especies que ocurren estrictamente en las zonas meso- y batipelágicas de los océanos. Se colectaron cinco especies de Oplophoridae: Acanthephyra acanthitelsonis Bate, 1888; A. quadrispinosa Kemp, 1939; Heterogenys monnioti Crosnier, 1987; Hymenodora glacialis (Buchholz, 1874) y Kemphyra corallina (A. Milne-Edwards, 1883). De éstas, H. monnioti y K. corallina son consideradas muy raras, ambas con escasos registros. Solamente A. quadrispinosa y H. glacialis se han registrado previamente en el Atlántico sudoccidental; así la fauna de Oplophoridae de la CMA Sur parece más relacionada con la fauna del Atlántico este y océano Índico.

Based on the analysis of richness and distribution of strictly aquatic vascular plants, the states most relevant to wetlands conservation of Mexico and its associated flora were identified. A number of 240 species were identified, distributed in 106 genera and 62 families, including 227 native and 13 introduced. Such richness accounts 24% of the total estimated of aquatic plants in Mexico and 8.3% of endemism. The states that have the highest species number are Veracruz (145 species), Jalisco (123), Michoacán (115) and Tamaulipas (113). Iterative analysis points out the need to involve 13 states for the conservation of 100% of the native aquatic flora.

Con base en el análisis de la riqueza y distribución de las hidrófitas vasculares estrictas, se identificaron las entidades federativas más relevantes para la conservación de los humedales de México y su flora asociada. Se registraron 240 especies distribuidas en 106 géneros y 62 familias, incluyendo 227 nativas y 13 introducidas, lo que representa 24% del total de las plantas acuáticas estimadas para México, incluyendo 8.3% de endemismo. Los estados que registran la mayor cantidad de especies son Veracruz (145 especies), Jalisco (123), Michoacán (115) y Tamaulipas (113). Un análisis iterativo indica que es necesario involucrar a 13 estados para la conservación de 100% de la flora acuática nativa.

Lagoas marginais são caracterizadas por apresentar elevada diversidade biológica, devido à presença de macrófitas aquáticas nas suas zonas litorâneas, constituindo habitats de refúgio e alimento para comunidades associadas. Entre os seus integrantes, destacam-se os macroinvertebrados aquáticos, fonte de energia para predadores e ictiofauna. Em seis lagoas e em duas épocas distintas (março e agosto de 2009), os atributos ecológicos da comunidade de macroinvertebrados aquáticos associados à Eichhornia azurea foram comparados, identificando-se os fatores ambientais controladores. Uma vez que os atributos da comunidade de macroinvertebrados estão estritamente associados às variáveis abióticas de cada habitat distinto, nossa hipótese era de que cada local com a presença da mesma macrófita aquática flutuante (E. azurea) deveria ter uma típica composição e densidade de organismos. Foram identificados 50 taxa de macroinvertebrados, com maior riqueza registrada para os insetos aquáticos (37 taxa), distribuídos em oito ordens; sendo a ordem Diptera a mais abundante nos dois períodos de estudo. Por outro lado, maiores valores de riqueza total de taxa foram registrados em agosto. Oxigênio dissolvido e pH apresentaram o maior número de correlações significativas positivas com os diferentes taxa. Os animais mais frequentes, coletados nas seis lagoas estudadas em março e agosto de 2009, foram Hirudinea, Oligochaeta, Hydrachnidiae, Conchostraca, Ostracoda, Noteridae, Ceratopogonidae, Chironomidae, Culicidae, Caenidae, Pleidae, Aeshnidae, Libellulidae, Coenagrionidae e Nematoda. Apenas as densidades de Trichoptera, Ostracoda e Conchostraca apresentaram maior diferença significativa entre lagoas, em ambos os períodos de estudo. Considerando-se a composição de macroinvertebrados, diferenças significativas não foram registradas.

Marginal lakes are characterised by their having high biological diversity due to the presence of aquatic macrophytes in their coastal zones, providing habitats for refuge and food for animal community members. Among the fauna components associated with macrophytes, aquatic macroinvertebrates are important because they are an energy source for predators and fish. In six lakes and two different seasons (March and August 2009), the ecological attributes of aquatic macroinvertebrate community associated with Eichhornia azurea were compared and the controlling environmental factors were identified. Since the attributes of macroinvertebrate community are strictly associated with abiotic variables of each distinct habitat, our hypothesis was that each site associated with the same floating aquatic macrophyte (E. azurea) should have a typical composition and density of organisms. We identified 50 taxa of macroinvertebrates, with greater taxa richness for aquatic insects (37 taxa) divided into eight orders; the order Diptera being the most abundant in the two study periods. On the other hand, higher values of total taxa richness were recorded in August. Dissolved oxygen and pH presented the greatest number of significant positive correlations with the different taxa. The animals most frequently collected in the six lakes in March and August 2009 were Hirudinea, Oligochaeta, Hydrachnidae, Conchostraca, Ostracoda, Noteridae, Ceratopogonidae, Chironomidae, Culicidae, Caenidae, Pleidae, Aeshnidae, Libellulidae, Coenagrionidae and Nematoda. Only densities of Trichoptera, Ostracoda and Conchostraca presented the highest significant differences between lakes in both study periods and considering the composition of macroinvertebrates no significant differences were registered for macroinvertebrate composition.

Amostragens de morcegos na região neotropical geralmente, contêm poucas espécies insetívoras. Apesar da elevada riqueza de morcegos insetívoros, o uso de rede de neblina resulta em baixa captura dessa guilda. As mais comumente amostradas no sudeste do Brasil são Molossus molossus, Molossus rufus e Myotis nigricans, mesmo representados por reduzido número de capturas são capturados próximos aos seus refúgios. Apesar de ser conhecida a preferência de espécies de morcegos insetívoros por ambientes ripários, poucos estudos têm explorado esses ambientes. O objetivo deste trabalho é analisar a riqueza de morcegos insetívoros em 31 lagoas no Estado do Rio de Janeiro usando redes de neblina. Em 1.995 horas de esforço de coleta, foram obtidas 2.159 capturas de 26 espécies exclusivamente ou parcialmente insetívoras. Oito espécies foram capturadas somente sobre as lagoas. A espécie mais frequente foi Myotis nigricans. Foi observado que as lagoas margeadas de florestas se mostraram ricas. A riqueza de espécies de morcegos nas lagoas não se diferenciou pela presença ou não de vegetação aquática e entre as lagoas salobras e doces. A amostragem em lagoas de tamanho médio ou grande e próximas a áreas residenciais podem ser as mais produtivas para a captura de espécies insetívoras. Três espécies amostradas são raramente citadas em inventários faunísticos: Macrophyllum macrophyllum, Lophostoma brasiliensis e Thyroptera tricolor. A realização de coletas com redes de neblina abertas sobre águas calmas foi mais representativa de morcegos insetívoros e pode resultar em uma melhor amostragem da assembleia de morcegos.

Bat samplings in Neotropical region usually contain few insectivorous species. Despite the high richness of insectivorous bats, the use of mist nets results in low efficiency of this guild. The most commonly sampled in southeastern Brazil are Molossus molossus, Molossus rufus and Myotis nigricans but even represented by small number of captures and in general netted in proximity of its roosts. Although being known the preference of species of insectivorous bats by riparian habitats, few studies have explored until now the water. The aim of this study is to analyze the richness of insectivorous bats over 31 ponds in the State of Rio de Janeiro using mist nets. After 1,995 hours of sampling effort, we obtained 2,159 captures of 26 strictly and partially insectivorous species. Eight species were captured only over the ponds. The most frequent species was Myotis nigricans. Ponds with forested margins showed higher richness. Species richness in the ponds did not differ by presence or absence of aquatic vegetation and brackish ponds among that without communication with the sea. The sampling in ponds of medium size or large and close to residential areas maybe the most productive for the capture of insectivorous. Three sampled species are rarely cited in faunal inventories: Macrophyllum macrophyllum, Lophostoma brasiliensis and Thyroptera tricolor. Samplings with mist nets opened over calm waters were more representative of the insectivorous guild and result in a better sampling of the assembly of bats.

Resumo O presente estudo apresenta um tratamento taxonômico para as Podostemaceae da Região Sul do Brasil. Podostemaceae é a maior família de angiospermas estritamente aquáticas com centro de riqueza na região equatorial da América do Sul. Os estudos taxonômicos ainda são escassos para o Brasil. Para a Região Sul do Brasil são reconhecidos seis gêneros e 10 espécies. São apresentadas chaves dicotômicas e ilustrações para a identificação das espécies.

Abstract This study provides a taxonomic treatment of the Podostemaceae family in southern Brazil. Podostemaceae is the largest family of strictly aquatic angiosperms. The center of family richness is the equatorial region of South America. Taxonomic studies are still scarce in Brazil. For southern Brazil there are six genera and 10 species recognized. Dichotomous key and illustrations are presented for species identification.

Dune lakes of the coast of Veracruz, Mexico, are shallow freshwater lakes with suitable conditions for the establishment of herbaceous and arboreal wetlands. Most of the vegetation of the surrounding dunes has been transformed into pastures for grazing lands and sugar cane plantations. The objective of this paper is to describe and compare structure, composition and diversity of the wetland vegetation of 15 dune lakes in the rural area. Environmental parameters (pH, salinity, size, depth and number of dry months) were taken into account. Plant diversity of these lakes comprise 46 families (27 strictly aquatic) and 82 species, among them Sagittaria lancifolia, Pontederia sagittata, Ceratophyllum demersum. Species richness fluctuated between 5 and 33 species. The classification resulted in nine floristic wetland groups, three of them with grass species from the surrounding areas (Cynodon dactylon, Echinochloa pyramidalis). Ordination separated lakes based on pH and number of dry months. Management plans should be developed together with the owners to maintain both the use of these lakes and the composition and structure of their wetlands.

Los lagos interdunarios de la costa de Veracruz, México, son cuerpos de agua dulce, someros, que presentan condiciones favorables para el establecimiento de humedales herbáceos y arbóreos. Las dunas que los rodean han sido transformadas en potreros introduciéndose especies forrajeras y caña de azúcar. Nuestro objetivo es describir y comparar la estructura, composición y diversidad de la vegetación de humedales de 15 lagos interdunarios en la zona rural. Se tomaron en cuenta factores ambientales como pH, salinidad, tamaño, profundidad y número de meses secos. Se registraron 46 familias (27 de las cuales son acuáticas estrictas) y 82 especies, entre ellas Sagittaria lancifolia, Pontederia sagittata, Ceratophyllum demersum. La riqueza fluctuó entre 5 y 33 especies. La clasificación encontró nueve grupos florísticos en los humedales de estos lagos, y en tres de ellos aparecen especies de pastos usados en la ganadería (Cynodon dactylon, Echinochloa pyramidalis). El principal eje de variación en la ordenación separó a los lagos en función del pH y del número de meses que permanecen secos. Su conservación y uso sustentable requieren de planes de manejo conjuntos con los usuarios.

Information on the use of aquatic environments by two species of amphisbaenids (Amphisbaena amazonica Vanzolini, 1951 and Amphisbaena alba Linnaeus, 1758) are presented. These findings suggest that aquatic environments are not a barrier to these animals, until now considered as strictly fossorial. New studies on amphisbaenians in natural conditions are needed in order to better understand which species may use water environment during dispersal events and the frequency of this behavior in the group.

Patterns of distribution and richness of strictly aquatic vascular plants of the state of Tamaulipas, Mexico, were analyzed. We registered 93 species of strictly aquatic vascular plants, which 62 are typical from lentic environments. The Río Tamesí sub-basin contains the highest number of species (68, 73.1%). There are no endemic species to the state of Tamaulipas, but we found 2 species endemic to Mexico (Lobelia purpusii and Oserya coulteriana). Twenty nine species (31.2%) are considered rare, because they are present in a single sub-basin; only 2 species are widely distributed in most of them (Bacopa monnieri and Echinodorus berteroi). A parsimony analysis of endemicity (PAE) of the hydrological sub-basins represented in this state based on the shared presence of species suggested that the strictly aquatic vascular plants have a nested distributional pattern. We conclude that these plants in Tamaulipas are part of the same floristic unit and that their distribution follow altitudinal, latitudinal and climatic gradients.

Se analizaron los patrones de riqueza y distribución de las plantas vasculares acuáticas estrictas en el estado de Tamaulipas, México. Se registraron 93 especies, 62 de las cuales son típicas de ambientes lénticos. La subcuenca Río Tamesí fue la que registró el mayor número de especies (68, 73.1%). No se registraron especies endémicas del estado, aunque existen 2 especies restringidas al territorio mexicano (Lobelia purpusii y Oserya coulteriana). Se consideran como raras 29 especies (31.2%) por presentarse en una sola subcuenca y sólo 2 especies están distribuidas ampliamente en la mayoría de éstas (Bacopa monnieri y Echinodorus berteroi). Un análisis de parsimonia de endemismos (PAE) de las subcuencas hidrológicas del estado con base en la presencia compartida de especies reveló que las plantas acuáticas estrictas presentan un patrón de distribución anidado. Se concluye que las plantas vasculares acuáticas estrictas de Tamaulipas son parte de una misma unidad florística y que su distribución obedece a gradientes altitudinales, latitudinales y climáticos.

Foi realizado o levantamento florístico das hidrófitas fanerogâmicas de ambientes aquáticos temporários da planície costeira do norte fluminense. O material botânico foi coletado em 27 expedições entre setembro/1998 a julho/2001, herborizado e identificado segundo a metodologia tradicional. As exsicatas foram depositadas no Herbário da Universidade do Rio de Janeiro (HUNI). Foram encontrados 113 táxons, distribuídos em 40 famílias. Os ambientes estudados podem ser caracterizados floristicamente pela família Cyperaceae, representada por 23 táxons (cerca de 20%); seguida pelas famílias Fabaceae e Onagraceae (sete táxons), Poaceae (seis táxons), Asteraceae e Scrophulariaceae (cinco táxons) e Apiaceae, Lentibulariaceae e Polygonaceae (quatro táxons). Estes ambientes sofrem alterações fitofisionômicas marcantes relacionadas com a hidrogeologia. Algumas espécies são anuais, desaparecendo completamente na estiagem; outras suportam a seca, mas têm a população profundamente reduzida, alterando substancialmente a paisagem. Algumas espécies consideradas exclusivamente aquáticas foram encontradas em solo úmido, inclusive em floração. Isto demonstra a necessidade da inclusão de espécies anfíbias nos estudos da flora aquática pois, algumas vezes, a delimitação dos tipos biológicos não é muito definida, além de caracterizar de forma mais adequada estes ambientes.

A floristic inventory of phanerogamic hydrophytes from the temporary swampy environments of coastal plains of northern of Rio de Janeiro State was made. The botanical vouchers were collected in 27 expeditions between September/1998 and July/2001. They were herborized and identified by the traditional methodology. The exsicatae were deposited in the UNIRIO herbarium (HUNI). One hundred and thirteen taxa, distributed among 40 families were found. The environment analyzed could be floristically characterized by the Cyperaceae, represented by 23 taxa (ca. 20%), followed by Fabaceae and Onagraceae (seven taxa), Poaceae (six taxa), Asteraceae and Scrophulariaceae (five taxa) and Apiaceae, Lentibulariaceae and Polygonaceae (four taxa). These environments have great phytophysionomic changes according to hydrogeology. Some species are annual, disappearing completely in the dry season; another species tolerates the dryness but the population reduce drastically, changing substantially the landscape. Some species regarded as strictly aquatic were found in humid soil, producing flowers. This shows the necessity to include amphibious species on the aquatic flora studies because sometimes the boundaries between the biological types were not well defined.

The effects of 0.1; 0.2; 0.4 and 0.8 mlPQ/L were analized on a zooplankton community, to determine the most sensitive species and to analize the occurence of physical abnormalities. A total of 40 taxa were determined. Paraquat affected significantly the zooplankton density but not the species richness. A progressive state of deformation of these organisms was also observed. Paraquat showed to be highly toxic for the zooplankton, so this herbicide should be strictly regulated in aquatic and terrestrial ecosystems.