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Improving our ability to monitor fragmented tropical ecosystems is a critical step in supporting the stewardship of these complex landscapes. We investigated the structural characteristics of vegetation classes in Ucayali, Peru, employing a co-production approach. The vegetation classes included three agricultural classes (mature oil palm, monocrop cacao, and agroforestry cacao plantations) and three forest regeneration classes (mature lowland forest, secondary lowland forest, and young lowland vegetation regrowth). We combined local knowledge with spaceborne lidar from NASA's Global Ecosystem Dynamics Investigation mission to classify vegetation and characterize the horizontal and vertical structure of each vegetation class. Mature lowland forest had consistently higher mean canopy height and lower canopy height variance than secondary lowland forest (µ = 29.40 m, sd = 6.89 m vs. µ = 20.82 m, sd = 9.15 m, respectively). The lower variance of mature forest could be attributed to the range of forest development ages in the secondary forest patches. However, secondary forests exhibited a similar vertical profile to mature forests, with each cumulative energy percentile increasing at similar rates. We also observed similar mean and standard deviations in relative height ratios (RH50/RH95) for mature forest, secondary forest, and oil palm even when removing the negative values from the relative height ratios and interpolating from above-ground returns only (mean RH50/RH95 of 0.58, 0.54, and 0.53 for mature forest, secondary forest, and oil palm, respectively) (p < .0001). This pattern differed from our original expectations based on local knowledge and existing tropical forest succession studies, pointing to opportunities for future work. Our findings suggest that lidar-based relative height metrics can complement local information and other remote sensing approaches that rely on optical imagery, which are limited by extensive cloud cover in the tropics. We show that characterizing ecosystem structure with a co-production approach can support addressing both the technical and social challenges of monitoring and managing fragmented tropical landscapes.

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The cultural significance of the flora used by the native Asheninka Sheremashe community in Ucayali, Peru was determined. To do this, a fieldwork of over 4 months was conducted, involving semi-structured interviews with 106 residents through non-probabilistic convenience sampling. The community utilizes 139 plant species in their daily lives, belonging to 120 genera and 52 families, with the most abundant being Fabaceae, Arecaceae, Malvaceae, Solanaceae, Poaceae, and Rutaceae. Furthermore, 25.9% of the species are of significant importance to theinhabitants according to the Cultural Index (CI), such as Manihot esculenta, Theobroma cacao, Bixa orellana, Musa paradisiaca, Ficus insipida, among others. It can be concluded that the flora plays a prominent role in the life of the community, with the categories reporting the highest number of species being: food (29.35%), medicine (28.36%), culture (9.95%), construction (9.45%), lumber (6.97%), commerce (3.48%), craftsmanship (2.49%), toxic (2.49%), and other uses (7.46%)

Se determinó la importancia cultural de la flora empleada por la comunidad nativa Asheninka Sheremashe, en Ucayali, Perú. Para ello, se realizó un trabajo de campo de más de 4 meses, donde se aplicaron entrevistas semiestructuradas a 106 habitantes mediante un muestreo no probabilístico por conveniencia. La comunidad emplea 139 especies vegetales en su día a día, pertenecientes a 120 géneros y 52 familias; siendo las más abundantes las Fabaceae, Arecaceae, Malvaceae, Solanaceae, Poaceae y Rutaceae. Además, el 25.9% de las especies tiene gran importancia para los pobladores según el Índice Cultural (IC): Manihot esculenta, Theobroma cacao, Bixa orellana, Musa paradisiaca, Ficus insipida, entre otras. Se concluye que la flora tiene un rol preponderante en la vida de la comunidad, siendo las categorías que presentaron mayor reporte de especies: alimentación (29.35%), medicina (28.36%), cultura (9.95%), construcción (9.45%), aserrío (6.97%), comercio (3.48%), artesanía (2.49%), tóxico (2.49%) y otros usos (7.46%)

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Scientists increasingly draw on fishers' ecological knowledge (FEK) to gain a better understanding of fish biology and ecology, and inform options for fisheries management. We report on a study of FEK among fishers along the Lower Ucayali River in Peru, a region of exceptional productivity and diversity, which is also a major supplier of fish to the largest city in the Peruvian Amazon. Given a lack of available scientific information on stock status, we sought to identify temporal changes in the composition and size of exploited species by interviewing fishers from 18 communities who vary in years of fishing experience since the mid-1950s. We develop four FEK-based indicators to assess changes in the fish assemblage and compare findings with landings data. We find an intensification of fishing gear deployed over time and spatiotemporal shifts in the fish assemblage and reported declines in species weight, which point to a fishing-down process with declines across multiple species. This finding is reflected in a shifting baseline among our participants, whereby younger generations of fishers have different expectations regarding the distribution and size of species. Our study points to the importance of spillover effects from the nearby Pacaya-Samira National Reserve and community initiatives to support the regional fishery. Reference to fishers' knowledge also suggests that species decline is likely underreported in aggregated landings data. Despite the dynamism and diversity of Amazonian floodplain fisheries, simple FEK-based indicators can provide useful information for understanding fishing-induced changes in the fish assemblage. Fishers hold valuable knowledge for fishery management and conservation initiatives in the region.

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En este trabajo se presenta una lista actualizada de los registros de especies de peces de la cuenca del río Ucayali, Perú, provenientes de datos publicados y no publicados. Los resultados muestran que la cuenca del Ucayali presenta una ictiofauna rica y diversificada con el registro de 734 especies distribuidas en 15 órdenes, 49 familias y 292 géneros. La Ictiofauna está compuesta por peces miniatura (4%), peces pequeños (39%), medianos (41%), grandes (13%) y gigantes (3%). Los grupos dominantes son los Characiformes (312 especies, 43.0 %), Siluriformes (270 especies, 36.8%), Gymnotiformes (51 especies, 6.9%), y Cichliformes (50 especies, 6.8%). Parte de la ictiofauna es compartida con cuencas adyacentes como Marañón, y Amazonas peruano, principalmente en la región de confluencia, lo que contribuye a la notable diversidad de peces en la cuenca. Se observó una alta riqueza de especies con distribución restricta de los géneros Orestias, Astroblepus, Trichomycterus, Hemibrycon, entre otras especies, que ocurren en la región de cabeceras. Estimativos de riqueza de especies considerando su distribución por cada 100 m de altitud, indican que la cuenca del Ucayali esta subestimada, esperándose encontrar hasta 1125 especies. Los resultados aquí presentados son antecedentes que coadyuvaran a la toma de decisiones con fines de conservación y desarrollo sustentable en la región amazónica.

This study presents an updated checklists of the fish species recorded in the Ucayali River basin, Peru, from published and unpublished data. Ucayali River basin shows a rich and diversified ichthyofauna, with 734 species distributed in 15 orders, 49 families and 292 genera. It is composed by miniature fishes (4 %, < 2.6 cm of standard length), small fishes (39 %), medium fishes (41 %), large fishes (13 %) and giants (3 %). The dominant groups are Characiformes (312 species, 43.0 %), Siluriformes (270 species, 36.8 %), Gymnotiformes (51 species, 6.9 %) and Cichliformes (50 species, 6.8 %). Part of the ichthyofauna is shared with the adjacent basins as Marañón and Amazon, mainly in the confluence area, which contribute to the highest diversity of fishes in the Ucayali basin. High diversity of fishes with restricted distribution was observed, among them Orestias, Astroblepus, Trichomycterus, Hemibrycon genera that occur in the headwaters. Estimates of species richness considering their distribution per 100 m of altitude, show that the Ucayali basin is underestimated, expecting to find up to 1125 species. The results presented here are background information that will contribute to decision-making for conservation and sustainable development purposes in the Amazon region.

RESUMO

The doncella Pseudoplatystoma punctifer is an economically and ecologically important catfish in the Amazon basin. However, little is known about its age, growth and population dynamics parameters. This study aims to validate the formation of growth marks in vertebrae of individuals collected from two rivers systems of the Peruvian Amazon (Amazon-Marañón-Ucayali and Putumayo) and compare growth parameters using the von Bertalanffy growth function between sexes and systems. A total of 372 individuals from the Amazon-Marañón-Ucayali (AMU) system and 93 from the Putumayo River were analyzed. The formation of one growth ring per year was validated and the individual ages ranged from zero to nine years old. Females grew significantly larger than males in both systems. Both females and males grew significantly better in the AMU system than in the Putumayo River. Maximum observed length and size at maturity in the AMU system were lower than those reported in previous studies in the area, and together with an important proportion of juveniles in the catches, suggest that the species is heavily exploited. Further studies on the reproductive biology and population dynamics of the doncella are needed in order to implement management measures more in line with the current situation.(AU)

La doncella Pseudoplatystoma punctifer es un bagre de importancia económica y ecológica en la cuenca Amazonica. Pese a ello, poco se conoce acerca de parámetros de edad, crecimiento y dinámica poblacional. Este estudio tuvo como objetivo validar la formación de marcas de crecimiento en vértebras de individuos colectados en dos sistemas fluviales de la Amazonia Peruana (Amazonas-Marañón-Ucayali y Putumayo) y comparar los parámetros de crecimiento usando la función de von Bertalanffy entre sexos y sistemas. Fueron analizados 372 individuos del sistema Amazonas-Marañón-Ucayali (AMU) y 93 del Putumayo. Se validó la formación de un anillo de crecimiento por año, la edad osciló entre cero y nueve años. Las hembras fueron significativamente más grandes que los machos en ambos sistemas. Para ambos sexos el crecimiento fue significativamente mayor en el sistema AMU que en el Putumayo. Las máximas tallas y edades de primera madurez observadas en el sistema AMU fueron menores a las reportadas en estudios previos en el área, y junto con un considerable porcentaje de juveniles presentes en las capturas, se sugiere que la especie está siendo fuertemente explotada. Son necesarios estudios de biología reproductiva y dinámica poblacional de doncella para implementar medidas de manejo acordes a la situación actual.(AU)

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The catfish Calophysus macropterus is heavily exploited in the Amazon basin, yet its life history characteristics are poorly documented, hampering proper fisheries management. In order to fill this gap, monthly sampling in the upper Putumayo River and in the Amazonas, lower Marañón and Ucayali (AMU) rivers were carried out over several years (2013-2015 in the AMU, 2013-2017 in the Putumayo) to provide detailed information about its reproduction, growth and mortality patterns (using length frequency data). Reproduction, which occurs during the dry and early flooding season, was only observed in the upper Putumayo River and not in the sampled portion of the AMU system, suggesting that the species reproduces closer to the Andes than other pimelodid catfishes. Size at first sexual maturity did not differ significantly among sex or among river systems, ranging from 25-28 cm SL. In both river systems, females had a faster growth than males and both genders also tended to have a better growth in the AMU than in the upper Putumayo. Mortality and exploitation estimate all indicated overexploitation of the species in both river systems. The implications of these results for fisheries management and conservation are discussed.(AU)

El bagre Calophysus macropterus está fuertemente explotado en la cuenca Amazónica. Sin embargo, su ciclo de vida está poco documentado, lo que dificulta su gestión pesquera. Para llenar este vacío, se realizaron muestreos mensuales en el alto río Putumayo alrededor de Puerto Leguízamo y en el Amazonas y los ríos bajo Marañón y Ucayali (AMU) cerca de Iquitos durante varios años (2013-2015 en AMU, 2013-2017 en Putumayo) para generar información sobre su reproducción, crecimiento y mortalidad. La reproducción, que se produce durante la estación seca y el inicio de la inundación, sólo se observó en el curso superior del río Putumayo y no en la parte muestreada del sistema de la AMU, lo que sugiere que la especie se reproduce más cerca de los Andes que otros pimelodidos. El tamaño de primera madurez sexual no difirió entre sexos o entre sistemas fluviales, oscilando entre 25-28 cm. En ambos sistemas fluviales, las hembras tuvieron un crecimiento más rápido que los machos y ambos géneros también tendieron a tener un mejor crecimiento en el AMU que en el alto Putumayo. Estimaciones de mortalidad y explotación indicaron una sobreexplotación en ambos sistemas. Se discuten las implicaciones de estos resultados para la gestión y conservación de las pesquerías.(AU)

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Abstract This study presents an extensive review of published and unpublished occurrence records of fish species in the Loreto department. Located in the northeast of the country, Loreto is the most geographically extensive region in the Peruvian territory. Despite the increase in fish collections in Loreto in recent years, the ichthyofauna of this department needs to be more documented. Based on a database of scientific collections and bibliographic information, an updated checklist of the freshwater fishes from Loreto is presented. The results reveal a rich and diversified ichthyofauna, with 873 species distributed in 331 genera, 50 families and 15 orders. The main groups are Characiformes (42.6%), Siluriformes (34.8%), Gymnotiformes (8.6%) and Cichliformes (7.4%). Part of the ichthyofauna has restricted distribution for Loreto (4.7%). In addition, 9.0% of species from Loreto are used in fisheries. Meanwhile, 219 species (25%) were categorized according to the IUCN criteria where only six species (0.7%) are currently considered threatened species (CR, EN or VU). The results presented in this work indicate that this department needs more studies to know the biodiversity of fish, likewise, the information presented constitutes a contribution to the knowledge of fish diversity that would support environmental management actions and decision-making aimed at conserving one of the most diverse departments of Peru.

Resumen Este trabajo presenta una revisión de los registros de especies de peces, publicados y no publicados, del departamento de Loreto. Localizado al noreste del país, Loreto es el departamento más extenso del territorio peruano. A pesar del incremento en el número de las colectas de peces en Loreto en años recientes, la ictiofauna de este departamento necesita ser más documentada. Sustentado en los registros en bases de datos de colecciones científicas e información bibliográfica, se presenta una actualización de la lista de peces de agua dulce de Loreto. Los resultados revelaron una ictiofauna rica y diversificada, con 873 especies, distribuidas en 331 géneros, 50 familias y 15 órdenes. Los principales taxones fueron Characiformes (42.6%), Siluriformes (34.8%), Gymnotiformes (8.6%) y Cichliformes (7.4%). Parte de la ictiofauna tiene distribución restricta para Loreto (4.7%). Además, 9.0% de las especies son usadas en pesquerías de Loreto. Mientras tanto, 219 (25%) especies fueron categorizadas de acuerdo con los criterios de la IUCN, donde sólo seis especies (0.7%) son consideradas actualmente especies amenazadas (CR, EN o VU). Los resultados presentados en este trabajo señalan que este departamento necesita más estudios para conocer la biodiversidad de peces, así mismo, la información presentada constituye un aporte al conocimiento de la biodiversidad íctica que respaldarían las acciones de gestión ambiental y toma de decisiones destinados a conservar uno de los departamentos más diversos del Perú.

RESUMO

Hyphessobrycon chiribiquete n. sp. is described from the Río Caquetá drainage in Colombia and the Río Ucayali drainage in Peru, western Amazon. The new species is diagnosed from its congeners by having the following combination of characters: a conspicuous narrow midlateral stripe, starting on the sides of the body behind the opercle near the lateral line; lateral stripe overlapped anteriorly with a vertically elongated humeral blotch; inner premaxillary teeth pentacuspid; margin of anal fin falcate in mature males.

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RESUMO

BACKGROUND: Wildlife has been traditionally used by forest communities as a source of protein, and the Peruvian Amazon is no exception. The articulation of colonist and indigenous communities to urban centers and markets results in changes in livelihood strategies and impacts on wildlife populations. To address the threat of overhunting and forest conversion, we provide a generalized characterization of colonist and indigenous communities and their hunting activities near Pucallpa, Ucayali, Peru. METHODS: A semi-structured household survey was conducted to characterize hunters and describe their prey collections. The data were analyzed by conducting a Kruskal-Wallis test, a multiple regression analysis, and by estimating the harvest rate (H). RESULTS: Less wealthy households were more actively engaged in hunting for food security and as a livelihood strategy. Additionally, older hunters were associated with higher hunting rates. Although the percentage of hunters was relatively low, estimated hunting rates suggest overharvesting of wildlife. Lowland pacas (Cuniculus paca) were the most frequently hunted prey, followed by red brocket deer (Mazama americana) and primates. While hunting intensity was not significantly different between indigenous and colonist communities, hunting rate disparities suggest there are different types of hunters (specialized vs. opportunistic) and that prey composition differs between communities. CONCLUSION: Close monitoring of wildlife populations and hunting activities is ideal for more accurately determining the impact of hunting on wildlife population and in turn on forest health. In lack of this type of information, this study provides insight of hunting as a shifting livelihood strategy in a rapidly changing environment at the forest/agriculture frontier.

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El estudio presenta una lista comentada de especies de peces registradas en la cuenca del río Aguaytía. Son consideradas las colectas de diferentes años y estaciones climáticas entre 1942 y 2009. Es el primer inventario de los peces para esta cuenca, la cual es importante para el Parque Nacional Cordillera Azul. La metodología empleada para la recolección de las muestras incluyó principalmente colectas activas con redes de arrastre de 10x3 m y de 5x2 m y 6 mm de malla. La fijación y preservación de las muestras se realizo con formol al 10% y de etanol al 70%, respectivamente. Las muestras se encuentran en la Colección Ictiológica (MUSM) del Museo de Historia Natural de la Universidad Nacional Mayor de San Marcos. Fueron analizados 9917 ejemplares y registradas un total de 211 especies agrupadas en 28 familias y nueve órdenes

An annotated species fish list recorded in the Aguaytía River basin is presented. Fishes were collected between 1942 and 2009 in different years and seasons. This is the first inventories in Aguaytía river Basin, and for the Cordillera Azúl National Park. Fishes were mainly collected using seines of 10x3 m and of 5x2 m and 6 mm mesh. For fixation and preservation of samples were used 10% formaldehyde solution and 70% ethanol, respectively. Samples are in the Ichthyological Collection (MUSM) of the Museum of Natural History of San Marcos University. We analized 9917 specimens and recorded a total of 211 species of 28 families and nine orders

RESUMO

A new species of the relatively poorly known Neotropical freshwater stingray genus Plesiotrygon Rosa, Castello & Thorson, 1987 is described from the main channel and smaller tributaries (Ríos Itaya and Pachitea) of the upper Amazon basin in Peru. The first specimen to be collected, however, was from much farther east in Rio Solimões in 1996, just down-river from Rio Purus (specimen unavailable for this study). Plesiotrygon nana sp. nov., is a very distinctive and unusually small species of freshwater stingray (Potamotrygonidae), described here mostly from three specimens representing different size classes and stages of sexual maturity. Plesiotrygon nana sp. nov., is distinguished from its only congener, P. iwamae Rosa, Castello & Thorson, 1987, by numerous unique features, including: dorsal coloration composed of very fine rosettes or a combination of spots and irregular ocelli; very circular disc and snout; very small and less rhomboidal spiracles; short snout and anterior disc region; narrow mouth and nostrils; denticles on dorsal tail small, scattered, not forming row of enlarged spines; adult and preadult specimens with significantly fewer tooth rows; fewer caudal vertebrae; higher total pectoral radials; very small size, probably not surpassing 250 mm disc length or width, males maturing sexually at around 180 mm disc length and 175 mm disc width; distal coloration of tail posterior to caudal stings usually dark purplish-brown; and features of the ventral lateral-line canals (hyomandibular canal very narrow, infraorbital and supraorbital canals not undulated, supraorbital and infraorbital loops small and narrow, supraorbital loop very short, not extending posteriorly to level of mouth, jugular and posterior infraorbital canals short, not extending caudally to first gill slits, subpleural loop very narrow posteriorly; absence of anterior and posterior subpleural tubules). To provide a foundation for the description of P. nana sp. nov., morphological variation in P. iwamae was examined based on all type specimens as well as newly collected and previously unreported material. Two specimens topotypic with the male paratype of P. nana sp. nov., referred to here as Plesiotrygon cf. iwamae, are also reported. Relationships of the new species to P. iwamae are discussed; further characters indicative of Plesiotrygon monophyly are proposed, but the genus may still not be valid. Plesiotrygon nana sp. nov., is commercialized with some regularity in the international aquarium trade from Iquitos (Peru), an alarming circumstance because nothing is known of its biology or conservation requirements.

Uma nova espécie do relativamente desconhecido gênero de raia de água doce Neotropical Plesiotrygon Rosa, Castello & Thorson, 1987 é descrita do canal principal e de tributários menores (Ríos Itaya e Pachitea) do alto da bacia Amazônica do Peru. O primeiro exemplar coletado, porém, foi capturado em 1996 muito mais ao leste no Rio Solimões, pouco abaixo da sua confluência com o Rio Purus (exemplar não disponível para estudo). Plesiotrygon nana sp. nov., é uma espécie pequena, muito distinta e incomum de raia de água doce (Potamotrygonidae), descrita aqui principalmente a partir de três indivíduos representando diferentes classes de tamanho e estágios de maturação sexual. Plesiotrygon nana sp. nov., distingue-se da única espécie previamente conhecida, P. iwamae Rosa, Castello & Thorson, 1987, por inúmeras características únicas, incluindo: coloração dorsal composta por rosetas muito finas ou uma combinação de pontilhados e ocelos irregulares; disco e focinho muito circular; espiráculos rombóides e bem pequenos; focinho curto; boca e narinas estreitas; dentículos no dorso da cauda pequenos, dispersos, sem formação de fileira de espinhos desenvolvidos; espécimes adulto e pré-adulto com um número significativamente menor de fileiras de dentes; menos vértebras caudais; maior número total de raios peitorais; tamanho muito pequeno, provavelmente não ultrapassando 250 mm de comprimento ou largura de disco; maturidade sexual dos machos perto de 180 mm de comprimento de disco e 175 mm de largura de disco; coloração distal da cauda posterior ao espinho caudal normalmente marrom escuro arroxeado; e características dos seus canais ventrais da linha lateral (canal hiomandibular delgado, canais infraoribital e supraorbital não ondulados, voltas supraorbital e infraorbital pequenas e estreitas, volta supraorbital não se estendendo posteriormente ao nível da boca, canais jugular e infraorbital posterior pequenos, não se estendendo caudalmente ao primeiro par de fendas branquiais, volta subpleural muito delgada posteriormente). Para fundamentar a descrição de P. nana sp. nov., variações morfológicas em P. iwamae foram examinadas baseadas em todos os exemplares da série tipo e em outros recém-coletados mas até então não reportados. Dois espécimes topotípicos com o parátipo macho de P. nana sp. nov., aqui referidos como Plesiotrygon cf. iwamae, também são descritos. Relações evolutivas da espécie nova com P. iwamae são discutidas; caracteres indicativos da monofilia do gênero são propostos, mas este pode ainda não ser válido. Plesiotrygon nana sp. nov., é comercializada com alguma freqüência no mercado internacional de peixes ornamentais de Iquitos (Peru), uma circunstância alarmante já que nada é conhecido sobre sua biologia ou possíveis diretrizes para conservação.

RESUMO

A new species of the relatively poorly known Neotropical freshwater stingray genus Plesiotrygon Rosa, Castello & Thorson, 1987 is described from the main channel and smaller tributaries (Ríos Itaya and Pachitea) of the upper Amazon basin in Peru. The first specimen to be collected, however, was from much farther east in Rio Solimões in 1996, just down-river from Rio Purus (specimen unavailable for this study). Plesiotrygon nana sp. nov., is a very distinctive and unusually small species of freshwater stingray (Potamotrygonidae), described here mostly from three specimens representing different size classes and stages of sexual maturity. Plesiotrygon nana sp. nov., is distinguished from its only congener, P. iwamae Rosa, Castello & Thorson, 1987, by numerous unique features, including: dorsal coloration composed of very fine rosettes or a combination of spots and irregular ocelli; very circular disc and snout; very small and less rhomboidal spiracles; short snout and anterior disc region; narrow mouth and nostrils; denticles on dorsal tail small, scattered, not forming row of enlarged spines; adult and preadult specimens with significantly fewer tooth rows; fewer caudal vertebrae; higher total pectoral radials; very small size, probably not surpassing 250 mm disc length or width, males maturing sexually at around 180 mm disc length and 175 mm disc width; distal coloration of tail posterior to caudal stings usually dark purplish-brown; and features of the ventral lateral-line canals (hyomandibular canal very narrow, infraorbital and supraorbital canals not undulated, supraorbital and infraorbital loops small and narrow, supraorbital loop very short, not extending posteriorly to level of mouth, jugular and posterior infraorbital canals short, not extending caudally to first gill slits, subpleural loop very narrow posteriorly; absence of anterior and posterior subpleural tubules). To provide a foundation for the description of P. nana sp. nov., morphological variation in P. iwamae was examined based on all type specimens as well as newly collected and previously unreported material. Two specimens topotypic with the male paratype of P. nana sp. nov., referred to here as Plesiotrygon cf. iwamae, are also reported. Relationships of the new species to P. iwamae are discussed; further characters indicative of Plesiotrygon monophyly are proposed, but the genus may still not be valid. Plesiotrygon nana sp. nov., is commercialized with some regularity in the international aquarium trade from Iquitos (Peru), an alarming circumstance because nothing is known of its biology or conservation requirements.

Uma nova espécie do relativamente desconhecido gênero de raia de água doce Neotropical Plesiotrygon Rosa, Castello & Thorson, 1987 é descrita do canal principal e de tributários menores (Ríos Itaya e Pachitea) do alto da bacia Amazônica do Peru. O primeiro exemplar coletado, porém, foi capturado em 1996 muito mais ao leste no Rio Solimões, pouco abaixo da sua confluência com o Rio Purus (exemplar não disponível para estudo). Plesiotrygon nana sp. nov., é uma espécie pequena, muito distinta e incomum de raia de água doce (Potamotrygonidae), descrita aqui principalmente a partir de três indivíduos representando diferentes classes de tamanho e estágios de maturação sexual. Plesiotrygon nana sp. nov., distingue-se da única espécie previamente conhecida, P. iwamae Rosa, Castello & Thorson, 1987, por inúmeras características únicas, incluindo: coloração dorsal composta por rosetas muito finas ou uma combinação de pontilhados e ocelos irregulares; disco e focinho muito circular; espiráculos rombóides e bem pequenos; focinho curto; boca e narinas estreitas; dentículos no dorso da cauda pequenos, dispersos, sem formação de fileira de espinhos desenvolvidos; espécimes adulto e pré-adulto com um número significativamente menor de fileiras de dentes; menos vértebras caudais; maior número total de raios peitorais; tamanho muito pequeno, provavelmente não ultrapassando 250 mm de comprimento ou largura de disco; maturidade sexual dos machos perto de 180 mm de comprimento de disco e 175 mm de largura de disco; coloração distal da cauda posterior ao espinho caudal normalmente marrom escuro arroxeado; e características dos seus canais ventrais da linha lateral (canal hiomandibular delgado, canais infraoribital e supraorbital não ondulados, voltas supraorbital e infraorbital pequenas e estreitas, volta supraorbital não se estendendo posteriormente ao nível da boca, canais jugular e infraorbital posterior pequenos, não se estendendo caudalmente ao primeiro par de fendas branquiais, volta subpleural muito delgada posteriormente). Para fundamentar a descrição de P. nana sp. nov., variações morfológicas em P. iwamae foram examinadas baseadas em todos os exemplares da série tipo e em outros recém-coletados mas até então não reportados. Dois espécimes topotípicos com o parátipo macho de P. nana sp. nov., aqui referidos como Plesiotrygon cf. iwamae, também são descritos. Relações evolutivas da espécie nova com P. iwamae são discutidas; caracteres indicativos da monofilia do gênero são propostos, mas este pode ainda não ser válido. Plesiotrygon nana sp. nov., é comercializada com alguma freqüência no mercado internacional de peixes ornamentais de Iquitos (Peru), uma circunstância alarmante já que nada é conhecido sobre sua biologia ou possíveis diretrizes para conservação.

RESUMO

El presente estudio compara los patrones de diversidad de peces en la Cuenca del Alto Yurúa. El área de estudio comprendió tres sub cuencas: Beu, Breu y Yurúa, todas sin impacto antropogénico. Mediante pesca con redes de arrastre a orilla, se colectaron 10564 individuos y se identificaron 185 especies de peces. En escala regional, el promedio del índice de diversidad Shannon (H') para Beu fue de 2,02; para Breu 1,84 y para Yuruá 1,75. Según el análisis de rarefacción, Yurúa tuvo la riqueza de especies esperada más alta (91 spp.) en comparación con Beu (87) y Breu (68). En la escala local, los ambientes lóticos presentaron mayor riqueza y diversidad que los lénticos. La diversidad promedio (H') fue mayor en lóticos (Beu 2,04; Breu 1,90; y Yurúa 1,86), comparados con lénticos de los mismos (Beu 1,66; Breu 1,86; y Yurúa 1,82). La mayor diversidad de peces observada en ambiente lóticos podría explicarse por que la mayoría de peces amazónicos tienen el comportamiento de desplazarse por los canales principales de los ríos, mientras que los lagos pueden presentar condiciones de estrés estacional (alta presión de depredación y bajas concentraciones de oxígeno disuelto).

The present study compares the patterns of fish's diversity of the Alto Yurúa Basin. The study area included three sub basins: Beu, Breu and Yurúa, all without anthropogenic impact. Fishing was carried out with trawls, 10564 individuals were collected and 185 fish's species were identified. In regional scale, the average of the Shannon diversity index (H') for Beu was of 2,02; for Breu 1,84 and Yuruá 1,75. The rarefaction analysis shows to Yurúa with the highest species richness (91 spp.), in comparison with Beu (87) and Breu (68). In the local scale, the diversity average (H') was highest in lotic environments (Beu 2,04; Breu 1,90; and Yurúa 1,86), compared with respective lentics environments (Beu 1,66; Breu 1,86; and Yurúa 1,82). The highest diversity of fishes observed in lotic environments could be explained because the most of Amazonian fishes have the behavior to travel by the main channels of the rivers, while the lakes can have stress seasonal conditions (high depredation pressure and low concentrations of dissolved oxygen).

RESUMO

En las comunidades ribereñas a lo largo del Bajo Ucayali, siete varones y seis mujeres informantes fueron interrogados en forma independiente durante dos días, sobre sus conocimientos en relación a plantas medicinales con el objetivo de identificar las plantas de uso principal en afecciones femeninas y comparar este conocimiento entre varones y mujeres. Las entrevistas fueron estructuradas y dirigidas aplicando cuestionarios estandarizados. Se presentan plantas utilizadas para solucionar problemas femeninos como trastornos menstruales, control de natalidad, trabajo de parto y algunas afecciones ginecológicas. Las principales conclusiones son: 1) Aproximadamente 70 diferentes plantas se reportaron como útiles para esos propósitos; la mayor parte solamente se menciona una vez para el mismo propósito y algunas se reportaron repetidamente. 2) Aproximadamente 60% de los usos reportados a afecciones femeninas se refiere a plantas encontradas en huertos, chacras y purmas y 40% a especies del bosque. Esto corresponde a los que informaron sobre todo tipo de plantas para medicina, pero si miramos solamente a las plantas para control de fertilidad y natalidad más del 75% provienen de los alrededores de los caseríos. 3) El conocimiento de hombres y mujeres es relativamente uniforme, probablemente a causa de tratamientos combinando el uso de hierbas cultivadas (más conocidas por mujeres) y árboles del bosque (más conocidos por hombres). De las hierbas cultivadas se usaron mayormente las hojas y de los árboles del bosque corteza, látex y res ma.

Assuntos