Estimated richness and environmental correlates of miniature fish assemblages in the rio Jacundá, Brazil

South America is home to more miniature fishes (<26 mm in standard length) than any other continent. Despite this diversity, the ecology of miniature fishes is poorly studied. To promote the study of miniature fish ecology, we investigated patterns in total richness, assemblage structure and environmental correlates for miniature fishes in the rio Jacundá drainage of the Lower Amazon River basin, Pará State. Based on multi-pass dip-netting of leaf litter at 20 locations distributed across two sites, we collected miniature species and used rarefaction to estimate 9 to 14 species might be present. The miniature fish assemblage at the upstream site was a nested subset of the downstream site, and water pH and canopy cover, two features known to be altered by deforestation, correlated most strongly with assemblage variation. Our work represents one of the first quantitative assessments of environmental correlates with miniature fish assemblages and highlights research topics that should be investigated further to promote conservation and preservation of the overlooked and understudied Amazonian diminutive freshwater fish fauna.(AU)

A América do Sul abriga o maior número de peixes miniaturas (<26 mm de comprimento padrão) do que qualquer outro continente. Apesar dessa diversidade, a ecologia dos peixes miniaturas é pouco estudada. Visando promover estudos de ecologia de peixes miniaturas, investigamos padrões de riqueza total, estrutura da assembleia e fatores ambientais correlacionados para peixes miniaturas no rio Jacundá, drenagem do baixo rio Amazonas, Pará. Com base em múltiplas passagens de redes no sedimento em 20 pontos distribuídos em dois locais, coletamos espécies miniaturas e usamos rarefação para estimar que 9 a 14 espécies podem estar presentes. A assembleia de peixes miniaturas no local à montante foi um subgrupo aninhado na assembleia no local à jusante, e pH da água e cobertura de copas, dois fatores sabidamente alterados por desmatamento, foram os mais correlacionados com a variação na assembleia. Nosso trabalho representa um dos primeiros estudos quantitativos de fatores ambientais correlacionados às assembleias de peixes miniaturas e ressalta um tópico de pesquisa que deveria ser melhor investigado para promover a conservação da pouco conhecida fauna de peixes diminutos da Amazônia.(AU)

Diversity of Ophioniformes wasps (Hymenoptera: Ichneumonidae) in a Central-West Brazilian Savanna area

This study aimed to assess the diversity, abundance and seasonal dynamics of Ophioniformes wasps collected throughout a year, as recorded in Malaise traps set at the Reserva Ecológica da Universidade Estadual do Mato Grosso do Sul, a Brazilian Savanna area in Aquidauana city, MS. A total of 621 specimens of Ophioniformes belonging to 11 subfamilies, 30 genera and 106 species were sampled. Despite the impressive number of species found, in a pattern of a few relatively abundant species and many rare ones, our data estimate even higher richness, probably between 125 to 165 species in the studied area. The genera Diadegma, Nonnus, Diradops, Meniscomorpha, Syzeuctus, Ophiopterus and Thyreodon are recorded for the first time in Mato Grosso do Sul State. Among the climatic variables evaluated, mean temperature and relative humidity were positively and significantly correlated with richness and abundance. Our data highlights the huge unknown species richness of these parasitoids in Brazil and the need of taxonomic studies efforts in the future.(AU)

Ontogenetic skull variation in an Amazonian population of lowland tapir, Tapirus terrestris (Mammalia: Perissodactyla) in the department of Loreto, Peru / Variación ontogenética de cráneos en una población amazónica del tapirsudamericano, Tapirus terrestris (Mammalia: Perissodactyla) en Loreto, Perú

The skulls of 54 specimens of the South American tapir, Tapirus terrestris collected in the department of Loreto, Peru were measured, analyzed and compared to investigate skull development of this species. Univariate, multivariate and allometric analyses were performed using 32 skull variables through traditional morphometrics. Significant skull shape variation was detected among ontogenetic classes. Young individuals (class I, n = 22) showed higher variation than subadults and adults (class II, n = 23 and class III, n = 9), without evidence of sexual dimorphism (males = 35, females = 19). Principal component analyses and discriminant function analysis showed almost complete separation of the age classes. Allometric analysis indicated a tendency of unproportioned cranial growth. All our samples come from the same population living under the same ecological condition, which eliminates the effect of confounding variables related to habitat on the pattern of ontogenetic variation of this anatomical structure.

Se midió, analizó y comparó 54 cráneos de tapir sudamericano, Tapirus terrestris recolectados en el departamento de Loreto, Perú, para investigar el desarrollo craneal de esta especie. Se realizaron análisis univariados, multivariados y alométricos de los cráneos utilizando 32 variables mediante morfometría tradicional. Se detectó una variación significativa de la forma del cráneo entre clases ontogenéticas. Los individuos más jóvenes (clase I, n = 22) mostraron mayor variación que subadultos y adultos (clases II, n = 23 y III, n = 9), pero sin evidencia de dimorfismo sexual (machos = 35, hembras = 19). Un análisis de componentes principales y un análisis de función discriminante mostraron una separación casi completa de las clases ontogenéticas. El análisis alométrico indicó una tendencia de crecimiento craneal desproporcionado. Todas nuestras muestras provienen de la misma población que vive bajo la misma condición ecológica, lo que elimina el efecto de confusión de variables relacionadas con el hábitat sobre el patrón de variaciones ontogenéticas de esta estructura anatómica.

Ontogenetic skull variation in an Amazonian population of lowland tapir, Tapirus terrestris (Mammalia: Perissodactyla) in the department of Loreto, Peru / Variación ontogenética de cráneos en una población amazónica del tapirsudamericano, Tapirus terrestris (Mammalia: Perissodactyla) en Loreto, Perú

The skulls of 54 specimens of the South American tapir, Tapirus terrestris collected in the department of Loreto, Peru were measured, analyzed and compared to investigate skull development of this species. Univariate, multivariate and allometric analyses were performed using 32 skull variables through traditional morphometrics. Significant skull shape variation was detected among ontogenetic classes. Young individuals (class I, n = 22) showed higher variation than subadults and adults (class II, n = 23 and class III, n = 9), without evidence of sexual dimorphism (males = 35, females = 19). Principal component analyses and discriminant function analysis showed almost complete separation of the age classes. Allometric analysis indicated a tendency of unproportioned cranial growth. All our samples come from the same population living under the same ecological condition, which eliminates the effect of confounding variables related to habitat on the pattern of ontogenetic variation of this anatomical structure.(AU)

Se midió, analizó y comparó 54 cráneos de tapir sudamericano, Tapirus terrestris recolectados en el departamento de Loreto, Perú, para investigar el desarrollo craneal de esta especie. Se realizaron análisis univariados, multivariados y alométricos de los cráneos utilizando 32 variables mediante morfometría tradicional. Se detectó una variación significativa de la forma del cráneo entre clases ontogenéticas. Los individuos más jóvenes (clase I, n = 22) mostraron mayor variación que subadultos y adultos (clases II, n = 23 y III, n = 9), pero sin evidencia de dimorfismo sexual (machos = 35, hembras = 19). Un análisis de componentes principales y un análisis de función discriminante mostraron una separación casi completa de las clases ontogenéticas. El análisis alométrico indicó una tendencia de crecimiento craneal desproporcionado. Todas nuestras muestras provienen de la misma población que vive bajo la misma condición ecológica, lo que elimina el efecto de confusión de variables relacionadas con el hábitat sobre el patrón de variaciones ontogenéticas de esta estructura anatómica.(AU)

Larval fish assemblages in nearshore waters of southeast Gulf of California: vertical and temporal patterns

The influence of salinity and temperature on larval fish assemblages, as well as, temporal and vertical patterns on larval fish assemblages off the inlet of the Presidio River, southeast coast of the Gulf of California were evaluated. Samplings for ichthyoplankton and environmental parameter measurements were carried out at three depths, in five sampling sites, during September and December 1994, and April and June 1995. Anchovies and herrings (Clupeiformes) were the most abundant larval fish accounting for 77% of the total abundance. A significant relationship between salinity and the abundance of larval herrings (Opisthonema medirastre and O. dovii) and between the water temperature and the abundance of the weakfish (Cynoscion reticulatus) was found. Anchovies (Anchoa lucida, A. walkeri, and A. nasus) were present in all sampled months, while O. medirastre and O. dovii occurred in December and June, and C. reticulatus in September. Larvae of pelagic fish were more abundant near the surface, while larvae of demersal fish were more abundant near the bottom. The present study, by emphasising the importance of considering temporal and vertical changes in larval fish assemblages in coastal environments with ecological and economic importance, will be useful for designing more efficient sampling programs.(AU)

Se evaluó la influencia de la salinidad y la temperatura, así como patrones temporales y verticales en la comunidad de larvas de peces enfrente del río Presidio, costa sudeste del Golfo de California. Los muestreos de ictioplancton y las mediciones de los parámetros ambientales fueron realizados a tres profundidades, en cinco sitios de muestreo, durante septiembre y diciembre de 1994, y abril y junio de 1995. Las anchoas y sardinas (Clupeiformes) fueron las larvas de peces más abundantes representando el 77% de la abundancia total. Se encontró una relación significativa entre la salinidad y la abundancia de larvas de sardinas (Opisthonema medirastre and O. dovii), y entre la temperatura del agua y la abundancia de la corvina rayada (Cynoscion reticulatus). Las anchoas (Anchoa lucida, A. walkeri y A. nasus) estuvieron presentes en todos los meses muestreados, mientras que O. medirastre y O. dovii ocurrieron en diciembre y junio, y C. reticulatus en septiembre. Las larvas de peces pelágicos fueron más abundantes cerca de la superficie, mientras que las larvas de peces demersales fueron más abundantes cerca del fondo. El presente estudio, al enfatizar la importancia de considerar los cambios temporales y verticales en el ensamblaje de larvas de peces en ambientes costeros con importancia ecológica y económica, será útil para diseñar programas de muestreo más eficientes.(AU)

Larval fish assemblages in nearshore waters of southeast Gulf of California: vertical and temporal patterns

The influence of salinity and temperature on larval fish assemblages, as well as, temporal and vertical patterns on larval fish assemblages off the inlet of the Presidio River, southeast coast of the Gulf of California were evaluated. Samplings for ichthyoplankton and environmental parameter measurements were carried out at three depths, in five sampling sites, during September and December 1994, and April and June 1995. Anchovies and herrings (Clupeiformes) were the most abundant larval fish accounting for 77% of the total abundance. A significant relationship between salinity and the abundance of larval herrings (Opisthonema medirastre and O. dovii) and between the water temperature and the abundance of the weakfish (Cynoscion reticulatus) was found. Anchovies (Anchoa lucida, A. walkeri, and A. nasus) were present in all sampled months, while O. medirastre and O. dovii occurred in December and June, and C. reticulatus in September. Larvae of pelagic fish were more abundant near the surface, while larvae of demersal fish were more abundant near the bottom. The present study, by emphasising the importance of considering temporal and vertical changes in larval fish assemblages in coastal environments with ecological and economic importance, will be useful for designing more efficient sampling programs.(AU)

Se evaluó la influencia de la salinidad y la temperatura, así como patrones temporales y verticales en la comunidad de larvas de peces enfrente del río Presidio, costa sudeste del Golfo de California. Los muestreos de ictioplancton y las mediciones de los parámetros ambientales fueron realizados a tres profundidades, en cinco sitios de muestreo, durante septiembre y diciembre de 1994, y abril y junio de 1995. Las anchoas y sardinas (Clupeiformes) fueron las larvas de peces más abundantes representando el 77% de la abundancia total. Se encontró una relación significativa entre la salinidad y la abundancia de larvas de sardinas (Opisthonema medirastre and O. dovii), y entre la temperatura del agua y la abundancia de la corvina rayada (Cynoscion reticulatus). Las anchoas (Anchoa lucida, A. walkeri y A. nasus) estuvieron presentes en todos los meses muestreados, mientras que O. medirastre y O. dovii ocurrieron en diciembre y junio, y C. reticulatus en septiembre. Las larvas de peces pelágicos fueron más abundantes cerca de la superficie, mientras que las larvas de peces demersales fueron más abundantes cerca del fondo. El presente estudio, al enfatizar la importancia de considerar los cambios temporales y verticales en el ensamblaje de larvas de peces en ambientes costeros con importancia ecológica y económica, será útil para diseñar programas de muestreo más eficientes.(AU)

Integrative taxonomy reveals a new species of pacu (Characiformes: Serrasalmidae: Myloplus) from the Brazilian Amazon

Pacus of the genus Myloplus represent a formidable taxonomic challenge, and particularly so for the case of M. asterias and M. rubripinnis, two widespread and common species that harbor considerable morphological diversity. Here we apply DNA barcoding and multiple species discovery methods to find candidate species in this complex group. We report on one well-supported lineage that is also morphologically and ecologically distinct. This lineage represents a new species that can be distinguished from congeners by the presence of dark chromatophores on lateral-line scales, which gives the appearance of a black lateral line. It can be further diagnosed by having 25-29 branched dorsal-fin rays (vs. 18-24), 89-114 perforated scales from the supracleithrum to the end of hypural plate (vs. 56-89), and 98-120 total lateral line scales (vs. 59-97). The new species is widely distributed in the Amazon basin, but seems to have a preference for black- and clearwater habitats. This ecological preference and black lateral line color pattern bears a striking similarity to the recently described silver dollar Metynnis melanogrammus.(AU)

Pacus do gênero Myloplus representam um desafio taxonômico formidável, e particularmente o caso de M. asterias e M. rubripinnis, duas espécies amplamente distribuídas e comuns que abrigam uma considerável diversidade morfológica. Aplicamos aqui a tecnologia do DNA barcoding e múltiplos métodos de descoberta de espécies para encontrar possíveis espécies novas nesse grupo complexo. Registramos uma linhagem bem suportada que também é distinta morfológica e ecologicamente. Essa linhagem representa uma nova espécie que pode ser distinguida das demais congêneres por apresentar cromatóforos escuros nas escamas da linha lateral que conferem uma aparência de linha lateral preta. Ela pode ser adicionalmente diagnosticada por ter 25-29 raios ramificados na nadadeira dorsal (vs. 18-24), 89-114 escamas perfuradas do supracleitro até o final da placa hipural (vs. 56-89) e 98-120 escamas totais na linha lateral (vs. 59-97). A nova espécie é amplamente distribuída na bacia Amazônica, mas aparentemente possui preferência por habitats de água preta e clara. A preferência ecológica e o padrão de colorido escuro da linha lateral consistem em semelhanças impressionantes com o silver dólar recém descrito Metynnis melanogrammus.(AU)

Integrative taxonomy reveals a new species of pacu (Characiformes: Serrasalmidae: Myloplus) from the Brazilian Amazon

Pacus of the genus Myloplus represent a formidable taxonomic challenge, and particularly so for the case of M. asterias and M. rubripinnis, two widespread and common species that harbor considerable morphological diversity. Here we apply DNA barcoding and multiple species discovery methods to find candidate species in this complex group. We report on one well-supported lineage that is also morphologically and ecologically distinct. This lineage represents a new species that can be distinguished from congeners by the presence of dark chromatophores on lateral-line scales, which gives the appearance of a black lateral line. It can be further diagnosed by having 25-29 branched dorsal-fin rays (vs. 18-24), 89-114 perforated scales from the supracleithrum to the end of hypural plate (vs. 56-89), and 98-120 total lateral line scales (vs. 59-97). The new species is widely distributed in the Amazon basin, but seems to have a preference for black- and clearwater habitats. This ecological preference and black lateral line color pattern bears a striking similarity to the recently described silver dollar Metynnis melanogrammus.(AU)

Pacus do gênero Myloplus representam um desafio taxonômico formidável, e particularmente o caso de M. asterias e M. rubripinnis, duas espécies amplamente distribuídas e comuns que abrigam uma considerável diversidade morfológica. Aplicamos aqui a tecnologia do DNA barcoding e múltiplos métodos de descoberta de espécies para encontrar possíveis espécies novas nesse grupo complexo. Registramos uma linhagem bem suportada que também é distinta morfológica e ecologicamente. Essa linhagem representa uma nova espécie que pode ser distinguida das demais congêneres por apresentar cromatóforos escuros nas escamas da linha lateral que conferem uma aparência de linha lateral preta. Ela pode ser adicionalmente diagnosticada por ter 25-29 raios ramificados na nadadeira dorsal (vs. 18-24), 89-114 escamas perfuradas do supracleitro até o final da placa hipural (vs. 56-89) e 98-120 escamas totais na linha lateral (vs. 59-97). A nova espécie é amplamente distribuída na bacia Amazônica, mas aparentemente possui preferência por habitats de água preta e clara. A preferência ecológica e o padrão de colorido escuro da linha lateral consistem em semelhanças impressionantes com o silver dólar recém descrito Metynnis melanogrammus.(AU)

Las Podostemaceae como hábitat para los macroinvertebrados en arroyos de Misiones (Argentina)

Las Podostemaceae son importantes componentes de las mallas tróficas de los ambientes reófilos pero su importancia como hábitat para los invertebrados es poco conocida. En este estudio se analizó la variación temporal de la abundancia y riqueza de taxa de los macroinvertebrados asociados a Podostemum distichum y Podostemum muelleri (Malpighiales: Podostemaceae) en dos arroyos de bajo orden durante diferentes estaciones del año. La abundancia total promedio difirió entre fechas de muestreo, pero no entre arroyos. Se registraron 14 familias de macroinvertebrados distribuidas en 9 órdenes en ambos arroyos. El Análisis de Escalamiento Multidimensional No Métrico (NMDS) reflejó también diferencias en el patrón estacional. Tanto el coeficiente de similitud como el de complementariedad, indican que ambos arroyos fueron muy similares en cuanto a la composición de las familias de macroinvertebrados. Las especies de Podostemaceae dominantes en cada arroyo constituyen hábitats de diversidad intermedia de acuerdo al índice de diversidad utilizado.(AU)

Podostemaceae are important components of the trophic networks of rheophilic environments but their importance as habitats for invertebrates is little known. In this study, the abundance and taxa richness of macroinvertebrate assemblages associated with Podostemum distichum and Podostemum muelleri (Malpighiales: Podostemaceae) in two low order streams were analyzed across seasons. Mean macroinvertebrate abundance differed significantly among seasons but did not differ between streams. Nine orders of macroinvertebrates were recorded in both streams, comprising 14 families. Non- metric multidimensional scaling (NMDS) reflected some differences in the seasonal pattern, too. The coefficient of similarity and the complementarity indicate that both streams were very similar in terms of the composition of the macroinvertebrate families. The dominant Podostemceae species in each stream constitute intermediate diversity habitats for macroinvertebrates according to the diversity index used.(AU)

Las Podostemaceae como hábitat para los macroinvertebrados en arroyos de Misiones (Argentina)

Las Podostemaceae son importantes componentes de las mallas tróficas de los ambientes reófilos pero su importancia como hábitat para los invertebrados es poco conocida. En este estudio se analizó la variación temporal de la abundancia y riqueza de taxa de los macroinvertebrados asociados a Podostemum distichum y Podostemum muelleri (Malpighiales: Podostemaceae) en dos arroyos de bajo orden durante diferentes estaciones del año. La abundancia total promedio difirió entre fechas de muestreo, pero no entre arroyos. Se registraron 14 familias de macroinvertebrados distribuidas en 9 órdenes en ambos arroyos. El Análisis de Escalamiento Multidimensional No Métrico (NMDS) reflejó también diferencias en el patrón estacional. Tanto el coeficiente de similitud como el de complementariedad, indican que ambos arroyos fueron muy similares en cuanto a la composición de las familias de macroinvertebrados. Las especies de Podostemaceae dominantes en cada arroyo constituyen hábitats de diversidad intermedia de acuerdo al índice de diversidad utilizado.

Podostemaceae are important components of the trophic networks of rheophilic environments but their importance as habitats for invertebrates is little known. In this study, the abundance and taxa richness of macroinvertebrate assemblages associated with Podostemum distichum and Podostemum muelleri (Malpighiales: Podostemaceae) in two low order streams were analyzed across seasons. Mean macroinvertebrate abundance differed significantly among seasons but did not differ between streams. Nine orders of macroinvertebrates were recorded in both streams, comprising 14 families. Non- metric multidimensional scaling (NMDS) reflected some differences in the seasonal pattern, too. The coefficient of similarity and the complementarity indicate that both streams were very similar in terms of the composition of the macroinvertebrate families. The dominant Podostemceae species in each stream constitute intermediate diversity habitats for macroinvertebrates according to the diversity index used.

Duplicidad de la vena renal derecha en Didelphis aurita (Didelphimorphia: Didelphidae): reporte de un caso / Double right renal vein in Didelphis aurita (Didelphimorphia: Didelphidae): case report

El Didelphis aurita, conocido como comadreja de orejas negras, es un marsupial con amplia distribución en la América del Sur, frecuente tanto en los ambientes silvestres como antrópicos debido a su gran plasticidad ecológica. Animales de esta especie son comúnmente atendidos en la medicina de animales silvestres y vienen siendo empleados como modelos experimentales alternativos a especies tradicionales. El objetivo de ese trabajo fue relatar la ocurrencia de un caso de vena renal doble en un espécimen adulto, macho, de D. aurita. Para eso, se ha disecado un cadáver fijado y conservado en solución de formaldehído 10%, previamente inyectado con látex de color azul por la porción torácica de la arteria aorta para facilitar la disección. El espécimen poseía dos venas renales derechas, una vena craneal (11,3 mm) y otra caudal (10,0 mm) que drenaban distintamente para una vena cava caudal. La vena renal izquierda y las arterias renales eran únicas. Aunque la duplicidad de la vena renal es reportada en otras especies como perros, gatos y felideos silvestres, este es el primer relato en el género Didelphis. El conocimiento de las variaciones anatómicas vasculares es relevante para la correcta ejecución de procedimientos veterinarios y en la interpretación de hallazgos experimentales en relación con el sistema urogenital.(AU)

Didelphis aurita, known as black eared oposum, is a marsupial widely distributed in South America, frequently seen in both wild and anthropogenic environments due to its great ecological plasticity. This species is commonly treated in wildlife veterinary services and has been used as alternative experimental models instead of conventional species. The aim of this report was to describe a case of double renal vein in a male, adult, specimen of D. aurita. In order to make the dissection easier, the cadaver was fixed and preserved in 10 % formaldehyde solution, and previously injected with latex in blue color by the thoracic aorta to facilitate dissection. The specimen had two right renal veins, one cranial (11.3 mm) and other caudal (10.0 mm) that drained distinctly for caudal vena cava. The left renal vein and the renal arteries were single. Although double renal vein has been reported in other species, such as dogs, cats and wild felids, this is the first mention in the genus Didelphis. The knowledge of the vascular anatomical variations is relevant for the correct execution of veterinary procedures and the interpretation of experimental findings in urogenital system research.(AU)

Leaf Anatomy of Xylopia aromatica (Lam. ) Mart. (Annonaceae) occurring in a rocky savannah in the Brazilian Amazonian / Anatomia foliar de Xylopia aromatica (Lam. ) Mart. (Annonaceae) ocorrente em uma savana rochosa na Amazônia Brasileira

Savannas of the Amazon Region of Mato Grosso State have an unique ecological identity due to the complexity of the Cerrado-Amazon transition region, their geographical isolation and the physical-chemical properties of the soil. This study aimed to characterize the leaf anatomy of Xylopia aromatica, and to identify potential adaptive traits to the xeric environment. We collected adult leaves from X. aromatica from a Amazonian savannah located in the Nova Canãa do Norte city, Mato Grosso. The leaves were fixed and stored in 70% ethanol. Cross sections were obtained by free hand with the aid of a razor blade, stained with astra blue and basic fuchsin, and mounted on histological slides. Charactersconsidered adaptive: thick cuticle, epidermal cells with thickened walls, the presence of silica in theepidermis, trichomes, hypostomatic leaves, stomata on the same level as the other epidermal cells, presenceof hypodermis, and dorsiventral mesophyll with palisade parenchyma occupying more than 50%. Theanatomical characters presented are of great importance for the establishment and development of X.aromatica in xeric environments. They contribute to the protection of the leaves from many biotic andabiotic factors to which they are subjected, thus ensuring the species survival in the savannic environment.

A região de savana amazônica do Estado do Mato Grosso possui identidade ecológica própria, explicada pela complexa região de transição Cerrado-Amazônia, pelo isolamento geográfico e pelas propriedades físico-químicas do solo. O objetivo deste estudo foi caracterizar a anatomia foliar de Xylopiaaromatica (Lam.) Mart, identificando possíveis características adaptativas ao ambiente xerófilo. Foram coletadas folhas adultas de X. aromatica em savana amazônica, localizado no município de Nova Canaã do Norte - Mato Grosso. As folhas foram fixadas em FAA50 e armazenadas em etanol a 70%. Os cortes transversais foram obtidos a mão livre com auxílio de lâmina de barbear, corados com azul de Astra e fucsina básica e montados em lâminas histológicas. Caracteres aqui considerados adaptativos: cutículaespessa, células epidérmicas com paredes espessadas, presença de sílica na epiderme, tricomas, folhashipoestomáticas, estômatos no mesmo nível das demais células epidérmicas, presença de hipoderme, mesofilo dorsiventral com parênquima paliçádico ocupando mais de 50% e lacunoso bem compacto. Os caracteres anatômicos aqui apresentados são de grande importância para as espécies desenvolverem-se em ambientes xerófilos, demonstrando contribuição para a proteção das folhas a diversos fatores bióticos e abióticos aos quais esta se sujeita, garantindo a sobrevivência das espécies no ambiente savânico.

Leaf Anatomy of Xylopia aromatica (Lam. ) Mart. (Annonaceae) occurring in a rocky savannah in the Brazilian Amazonian / Anatomia foliar de Xylopia aromatica (Lam. ) Mart. (Annonaceae) ocorrente em uma savana rochosa na Amazônia Brasileira

Savannas of the Amazon Region of Mato Grosso State have an unique ecological identity due to the complexity of the Cerrado-Amazon transition region, their geographical isolation and the physical-chemical properties of the soil. This study aimed to characterize the leaf anatomy of Xylopia aromatica, and to identify potential adaptive traits to the xeric environment. We collected adult leaves from X. aromatica from a Amazonian savannah located in the Nova Canãa do Norte city, Mato Grosso. The leaves were fixed and stored in 70% ethanol. Cross sections were obtained by free hand with the aid of a razor blade, stained with astra blue and basic fuchsin, and mounted on histological slides. Charactersconsidered adaptive: thick cuticle, epidermal cells with thickened walls, the presence of silica in theepidermis, trichomes, hypostomatic leaves, stomata on the same level as the other epidermal cells, presenceof hypodermis, and dorsiventral mesophyll with palisade parenchyma occupying more than 50%. Theanatomical characters presented are of great importance for the establishment and development of X.aromatica in xeric environments. They contribute to the protection of the leaves from many biotic andabiotic factors to which they are subjected, thus ensuring the species survival in the savannic environment.(AU)

A região de savana amazônica do Estado do Mato Grosso possui identidade ecológica própria, explicada pela complexa região de transição Cerrado-Amazônia, pelo isolamento geográfico e pelas propriedades físico-químicas do solo. O objetivo deste estudo foi caracterizar a anatomia foliar de Xylopiaaromatica (Lam.) Mart, identificando possíveis características adaptativas ao ambiente xerófilo. Foram coletadas folhas adultas de X. aromatica em savana amazônica, localizado no município de Nova Canaã do Norte - Mato Grosso. As folhas foram fixadas em FAA50 e armazenadas em etanol a 70%. Os cortes transversais foram obtidos a mão livre com auxílio de lâmina de barbear, corados com azul de Astra e fucsina básica e montados em lâminas histológicas. Caracteres aqui considerados adaptativos: cutículaespessa, células epidérmicas com paredes espessadas, presença de sílica na epiderme, tricomas, folhashipoestomáticas, estômatos no mesmo nível das demais células epidérmicas, presença de hipoderme, mesofilo dorsiventral com parênquima paliçádico ocupando mais de 50% e lacunoso bem compacto. Os caracteres anatômicos aqui apresentados são de grande importância para as espécies desenvolverem-se em ambientes xerófilos, demonstrando contribuição para a proteção das folhas a diversos fatores bióticos e abióticos aos quais esta se sujeita, garantindo a sobrevivência das espécies no ambiente savânico.(AU)

Biomarcadores histológicos em brânquias de Sciades herzbergii (Siluriformes, Ariidae) capturados no Complexo Estuarino de São Marcos, Maranhão / Histological biomarkers in gills of Sciades herzbergii (Siluriformes, Ariidae) caught in the Estuarine Complex of São Marcos, Maranhão

Neste estudo, objetivou-se avaliar a qualidade ambiental de duas áreas do complexo estuarino de São Marcos, utilizando-se as alterações branquiais em Sciades herzbergii como biomarcadores de contaminação aquática. Foram realizadas coletas no período de estiagem (setembro/dezembro de 2015) e no período chuvoso (março/junho de 2016). Foram capturados 40 exemplares de S. herzbergii em dois locais distintos do complexo estuarino: A1) Porto do Itaqui Bacanga (área potencialmente impactada); A2) Igarapé do Puca, Alcântara (área controle). Foram registradas as variáveis abióticas: salinidade, temperatura, pH e oxigênio dissolvido. No laboratório, as brânquias de cada espécime foram fixadas em formol a 10% e mantidas em álcool a 70% até a execução da técnica histológica usual. As alterações branquiais identificadas nos peixes da área potencialmente contaminada foram: deslocamento do epitélio (DE), congestão (CO), aneurisma (AN), fusão lamelar (FL), hiperplasia (HI), dilatação capilar (DC), necrose (NE) e proliferação de células epiteliais (PCE). As alterações na região controle foram: deslocamento do epitélio (DE), fusão lamelar (FL), necrose (NE) e proliferação de células epiteliais (PCE). As alterações branquiais foram mais frequentes na região portuária (84%) do que na região controle (16%). Esses resultados indicam que os peixes da área potencialmente contaminada estão apresentando respostas biológicas ao estresse local.(AU)

This study aimed to compare an environmental quality of two areas of the estuarine complex of São Marcos using gills of changes in Sciades herzbergii as biomarkers of aquatic contamination. Samples were made during the dry season (September/ December 2015) and rainy season (March/ June 2016). They were captured 40 specimens of S. herzbergii at two different points of the estuarine complex: A1) Itaqui port (potentially contaminated area); A2) Igarapé do Puca, Alcântara (control area). Abiotic variables were recorded: salinity, temperature, pH and dissolved oxygen. In the laboratory, the gills of each species were fixed in 10% formaldehyde and kept in 70% alcohol until the usual histological technique was performed. The gill alterations identified in the fish of the potentially contaminated area were: epithelial displacement (DE), congestion (CO), aneurysm (AN), lamellar fusion (FL), hyperplasia (HI), capillary dilation (DC), necrosis and epithelial cell proliferation (PCE). The changes in the control region were: epithelial displacement (DE), lamellar fusion (FL), necrosis (NE) and epithelial cell proliferation (PCE). Gill alterations were more frequent in the port region (84%) than in the control region (16%). These results indicate that fish from the potentially contaminated area are presenting biological responses to local stress.(AU)

Biomarcadores histológicos em brânquias de Sciades herzbergii (Siluriformes, Ariidae) capturados no Complexo Estuarino de São Marcos, Maranhão / Histological biomarkers in gills of Sciades herzbergii (Siluriformes, Ariidae) caught in the Estuarine Complex of São Marcos, Maranhão

Neste estudo, objetivou-se avaliar a qualidade ambiental de duas áreas do complexo estuarino de São Marcos, utilizando-se as alterações branquiais em Sciades herzbergii como biomarcadores de contaminação aquática. Foram realizadas coletas no período de estiagem (setembro/dezembro de 2015) e no período chuvoso (março/junho de 2016). Foram capturados 40 exemplares de S. herzbergii em dois locais distintos do complexo estuarino: A1) Porto do Itaqui Bacanga (área potencialmente impactada); A2) Igarapé do Puca, Alcântara (área controle). Foram registradas as variáveis abióticas: salinidade, temperatura, pH e oxigênio dissolvido. No laboratório, as brânquias de cada espécime foram fixadas em formol a 10% e mantidas em álcool a 70% até a execução da técnica histológica usual. As alterações branquiais identificadas nos peixes da área potencialmente contaminada foram: deslocamento do epitélio (DE), congestão (CO), aneurisma (AN), fusão lamelar (FL), hiperplasia (HI), dilatação capilar (DC), necrose (NE) e proliferação de células epiteliais (PCE). As alterações na região controle foram: deslocamento do epitélio (DE), fusão lamelar (FL), necrose (NE) e proliferação de células epiteliais (PCE). As alterações branquiais foram mais frequentes na região portuária (84%) do que na região controle (16%). Esses resultados indicam que os peixes da área potencialmente contaminada estão apresentando respostas biológicas ao estresse local.(AU)

This study aimed to compare an environmental quality of two areas of the estuarine complex of São Marcos using gills of changes in Sciades herzbergii as biomarkers of aquatic contamination. Samples were made during the dry season (September/ December 2015) and rainy season (March/ June 2016). They were captured 40 specimens of S. herzbergii at two different points of the estuarine complex: A1) Itaqui port (potentially contaminated area); A2) Igarapé do Puca, Alcântara (control area). Abiotic variables were recorded: salinity, temperature, pH and dissolved oxygen. In the laboratory, the gills of each species were fixed in 10% formaldehyde and kept in 70% alcohol until the usual histological technique was performed. The gill alterations identified in the fish of the potentially contaminated area were: epithelial displacement (DE), congestion (CO), aneurysm (AN), lamellar fusion (FL), hyperplasia (HI), capillary dilation (DC), necrosis and epithelial cell proliferation (PCE). The changes in the control region were: epithelial displacement (DE), lamellar fusion (FL), necrosis (NE) and epithelial cell proliferation (PCE). Gill alterations were more frequent in the port region (84%) than in the control region (16%). These results indicate that fish from the potentially contaminated area are presenting biological responses to local stress.(AU)

The effects of heavy metals on the incidence of morphological deformities in Chironomidae (Diptera)

Streams in urban areas are strongly impacted by the input of organic matter and metals, for instance copper (Cu) and zinc (Zn). These metals are essential for the aquatic biota, but when absorbed in excess they are toxic. In Chiro nomidae larvae, the deleterious effects of heavy metals can be ascertained by analyzing the morphological deformities of the larval mentum, a structure of the oral cavity. In this study, we evaluated I) the bioavailability of Cu and Zn in urban stream sediments and II) the relationship between Cu and Zn concentrations and the incidence of deformities in the mentum of Chironomus larvae. Chironomid flies were collected from four locations in two streams at an urban area in southern Brazil. They were identified and the incidence of deformities in the mentum was quantified. Sediment samples were collected at the same locations where larvae were collected, to quantify the bioavailable fractions of Cu and Zn. The concentrations of Cu in the sediment were similar between the collection sites. However, Zn concentrations varied among sites, being greater in the stretch directly influenced by the input of the organic waste. In total, 2,895 Chironomid larvae were collected. The incidence of deformities in the mentum was above 30% and was correlated with the concentrations of Cu (r = 0.68) and Zn (r = 0.87). This correlation indicates that the municipal waste that is thrown into the citys streams has influenced the occurrence of deformities.

The effects of heavy metals on the incidence of morphological deformities in Chironomidae (Diptera)

Streams in urban areas are strongly impacted by the input of organic matter and metals, for instance copper (Cu) and zinc (Zn). These metals are essential for the aquatic biota, but when absorbed in excess they are toxic. In Chiro nomidae larvae, the deleterious effects of heavy metals can be ascertained by analyzing the morphological deformities of the larval mentum, a structure of the oral cavity. In this study, we evaluated I) the bioavailability of Cu and Zn in urban stream sediments and II) the relationship between Cu and Zn concentrations and the incidence of deformities in the mentum of Chironomus larvae. Chironomid flies were collected from four locations in two streams at an urban area in southern Brazil. They were identified and the incidence of deformities in the mentum was quantified. Sediment samples were collected at the same locations where larvae were collected, to quantify the bioavailable fractions of Cu and Zn. The concentrations of Cu in the sediment were similar between the collection sites. However, Zn concentrations varied among sites, being greater in the stretch directly influenced by the input of the organic waste. In total, 2,895 Chironomid larvae were collected. The incidence of deformities in the mentum was above 30% and was correlated with the concentrations of Cu (r = 0.68) and Zn (r = 0.87). This correlation indicates that the municipal waste that is thrown into the citys streams has influenced the occurrence of deformities.(AU)

In honor of conservation of the Brazilian Atlantic Forest: description of two new damselflies of the genus Forcepsioneura discovered in private protected areas (Odonata: Coenagrionidae)

Two new Brazilian Protoneurinae damselflies, Forcepsioneura regua sp. nov. (holotype male deposited in DZRJ: Brazil, Rio de Janeiro State, Cachoeiras de Macacu municipality, RPPN Reserva Ecológica de Guapiaçu) and Forcepsioneura serrabonita sp. nov. (holotype male deposited in DZRJ: Brazil, Bahia State, Camacan municipality, RPPNs Serra Bonita) , are described, illustrated and diagnosed based on males and females. The bluish and smaller F. regua sp. nov. has been confused with at least three previously described species, being very similar to the type species of Forcepsioneura, F. garrisoni Lencioni, 1999, but lacking a defined tubercle-like process on the posterolateral margin of the median lobe of the prothorax in both sexes, which allows it to be distinguished from all other known species. The shape of the cercus of the male of F. serrabonita sp. nov. is similar to that of F. grossiorum Machado, 2001 and F. lucia Machado, 2000, two species with very short ventrobasal process. However, it differs from them mainly by the mediobasal process of the cercus, which is rounded in dorsal view and almost not visible in lateral view. The taxonomic status of Forcepsioneura is discussed and a comparison with the other species of the genus is provided. Based on size, habitat and coloration, Forcepsioneura can be informally divided into two groups: (1) large, orange-black and montane species, including F. grossiorum, F. itatiaiae (Santos, 1970), F. lucia and F. serrabonita sp. nov.; (2) small, bluish and lowland species, including F. garrisoni, F. haerteli Machado, 2001, F. regua sp. nov. and F. sancta (Hagen in Selys, 1860). Our findings highlight the urgency in directing collecting efforts to unexplored areas, as well as the importance of private preserves that harbor the type localities as guardians of the threatened and diverse Atlantic Forest diversity.[...](AU)

In honor of conservation of the Brazilian Atlantic Forest: description of two new damselflies of the genus Forcepsioneura discovered in private protected areas (Odonata: Coenagrionidae)

Two new Brazilian Protoneurinae damselflies, Forcepsioneura regua sp. nov. (holotype male deposited in DZRJ: Brazil, Rio de Janeiro State, Cachoeiras de Macacu municipality, RPPN Reserva Ecológica de Guapiaçu) and Forcepsioneura serrabonita sp. nov. (holotype male deposited in DZRJ: Brazil, Bahia State, Camacan municipality, RPPNs Serra Bonita) , are described, illustrated and diagnosed based on males and females. The bluish and smaller F. regua sp. nov. has been confused with at least three previously described species, being very similar to the type species of Forcepsioneura, F. garrisoni Lencioni, 1999, but lacking a defined tubercle-like process on the posterolateral margin of the median lobe of the prothorax in both sexes, which allows it to be distinguished from all other known species. The shape of the cercus of the male of F. serrabonita sp. nov. is similar to that of F. grossiorum Machado, 2001 and F. lucia Machado, 2000, two species with very short ventrobasal process. However, it differs from them mainly by the mediobasal process of the cercus, which is rounded in dorsal view and almost not visible in lateral view. The taxonomic status of Forcepsioneura is discussed and a comparison with the other species of the genus is provided. Based on size, habitat and coloration, Forcepsioneura can be informally divided into two groups: (1) large, orange-black and montane species, including F. grossiorum, F. itatiaiae (Santos, 1970), F. lucia and F. serrabonita sp. nov.; (2) small, bluish and lowland species, including F. garrisoni, F. haerteli Machado, 2001, F. regua sp. nov. and F. sancta (Hagen in Selys, 1860). Our findings highlight the urgency in directing collecting efforts to unexplored areas, as well as the importance of private preserves that harbor the type localities as guardians of the threatened and diverse Atlantic Forest diversity.[...]

Description of the postembryonic stages of Boeckella poopoensis (Crustacea, Copepoda, Centropagidae)

Boeckella poopoensis Marsh, 1906 es uno de los copépodos más frecuentes en el zooplancton de los lagos salinos sudamericanos, donde generalmente es la especie que más contribuye a la biomasa de la comunidad zooplanctónica. A pesar de su amplia distribución geográfica y su importancia ecológica, las características que distinguen sus estadios postembrionarios no son conocidas, lo que no permite conocer detalladamente la estructura y dinámica de sus poblacionales naturales. El objetivo de este trabajo fue describir la morfología de los estadios postembrionarios y compararlos con los de otras especies de Centropagidae. Los especímenes estudiados fueron obtenidos de un cultivo monoespecífico aclimatado en laboratorio. El linaje proviene del lago El Carancho (65°03W, 37º27S). La identificación de los estadios se hizo de acuerdo a los caracteres establecidos para los copépodos calanoideos. En base a todos los estados de desarrollo, algunas de las características que distinguen a B. poopoensis de otras especies del género son: lóbulos de los nauplios con el mismo número de sedas de igual longitud; la segmentación del cuerpo se inicia en el estadio de nauplio III; el dimorfismo sexual empieza a notarse a partir del copepodito IV (aunque sólo es evidente en la pata V); el endopodito de la pata V de los copepoditos V machos y hembras es biarticulado pero, mientras las hembras adquieren sedas con respecto al estadio anterior, los machos las pierden, llegando a ser glabras como en los adultos. Los copepoditos V no presentan características típicas de los adultos, tales como, el ala toracal izquierda más desarrollada en las hembras y la antena derecha geniculada en los machos. Todos los estadios de B. poopoensis son más grandes que los correspondientes a otros centropágidos y los estadios inmaduros muestran su propio patrón de sedas, con un número ligeramente menor que el de otras especies de la familia.(AU)

Boeckella poopoensis Marsh, 1906 is one of the most common copepods in the saline lakes of South America, where generally is the species that greater contributes to the zooplankton community biomass. Despite of its wide geographic distribution and ecological importance, the characteristics of the postembryonic stages are unknown, which prevents a detailed understanding of the structure and dynamics of natural populations. The objective of this work was to describe the morphology of the postembryonic stages and to compare it with other species of Centropagidae. The specimens were obtained from a monospecific culture acclimatized in the laboratory. The lineage comes from El Carancho shallow lake (65°03W, 37°27S). The identification of the postembryonic stages was performed according to the characteristics established for copepod calanoids. Based in all developing stages, some characteristics that distinguish B. poopoensis from another species of the genus are: lobes of nauplii with the same number of setae of equal length; beginning of body segmentation from nauplii III; sexual dimorphism from copepodite IV (although only evident in the V leg); the endopod of the V leg of copepodites V males and females are biarticulate, but while females endopod add setae respect to the previous stage, males endopod lose them and remain glabrous as in the adults. Copepodites V do not present characteristics typical of adults, such as, the most developed thoracic left wing of females and in the geniculate right antenna of males. All stages of B. poopoensis are larger than those corresponding to other species of centropagids, and in the immature stages, the appendages show their own patterns of setae and have a slightly smaller number of setae than that of the other species of the family.(AU)