Liste commentée des poissons de l'Amazonie bolivienne

Après une brève présentation de l'Amazonie bolivienne, des milieux prospectés, de l'effort de pêche, des travaux anciens et récents, les auteurs founissent une liste commentée des poissons rencontrés. Sur l'ensemble de l'Amazonie bolivienne 389 espèces ont été identifiées. Les différences entre les quatre grands fleuves (Béni, Madre de Dios, Mamoré, Guaporé) constituant le Haut-Madeira sont soulignées. Dans le bassin du Mamoré, intensément prospecté, 327 espèces ont été récoltées avec une forte dominance des siluriformes (45%) et des #Characoidei$ (39%). Dans ce bassin les auteurs distinguent une zone de plaine et une zone andine (au dessus de 200 m) séparée en trois sous-zones en fonction des associations ichtyques rencontrées. (Résumé d'auteur

Morfologia comparada da cintura pélvica de representantes da superfamília loricarioidea (ostariophysi siluriformes)

The morphology of the pelvic girdle is compared throughout the six families of Loricarioidea. Representatives of the families were: Nematogenyidae (1 species), Trichomycteridae (7 species), Callichthyidae (6 species), Scoloplacidae (2 species), Astroblepidae (1 species) and Loricariidae (8 species). All families showed synapomorphies on the pelvic girdle. Nematogenyidae has a laminar extension on the basipterygium and cartilages on the 1 st and 2 nd pelvic rays; Trichomycteridae, besides showing a large diversity of shapes of pelvics, have structures such as fused cartilage, very long internal anterior processes and posterior cartilage on basipterygium; Callichthyidae showed a very peculiar shape of pelvic girdle but very conservative throughout the family, and some features like a unique conexion of the pelvics with the axial skeleton, strong tridimensional shape of the basipterygium and external anterior processes modified; Scoloplacidae also showed a very peculiar and conservative pelvic girdle, without anterior or posterior processes, and with a reduced and posterior sutural joint between the basipterygia; Astroblepidae shows a very distinguished pelvic girdle, with long posterior processes, racquet-like lateropterygium and musculature well developed; and Loricariidae showed a spike- like lateropterygium, synchondral joint of the basipterygia between sutures or not, and well developed condyles for articulation of the pelvic rays. Nematogenyidae and Trichomycteridae share a similar disposition of the anterior processes and the presence of unfused cartilage between the basipterygia. The other Loricarioidea, or ‘advanced Loricarioidea’, already show sutural joints between the basipterygia. Astroblepidae and Loricariidae share, among other features, the presence of the lateropterygium, presence of condyles for articulation of the pelvic rays and synchondral joint followed by sutures. Some new features are described for some of the families (Nematogenyidae, Trichomycteridae and Astroblepidae). The present work brought additional support to the current hypothesis of relationship among Loricarioidea families.A morfologia da cintura pélvica de representantes das seis famílias de Loricarioidea é comparada. Foram usados representantes de Nematogenyidae (1 espécie), Trichomycteridae (7 espécies), Callichthyidae (6 espécies), Scoloplacidae (2 espécies), Astroblepidae (1 espécie) e Loricariidae (8 espécies). Todas as famílias apresentaram sinapomorfias relacionadas à cintura pélvica. Nematogenyidae apresenta uma expansão laminar no basipterígio e cartilagens nos 1o e 2o raios pélvicos; Trichomycteridae, apesar de possuirem uma grande diversidade de formas de pélvicas, apresentaram características como presença de cartilagem fusionada, processos anteriores internos extremamente longos e presença de cartilagem posterior; Callichthyidae apresentaram uma cintura pélvica muito diferenciada mas conservada dentro da família, e como características únicas a conexão da pélvica com o esqueleto axial em alguns representantes, tridimensionalidade acentuada na forma do basipterígio e modificações nos processos anteriores externos; Scoloplacidae também apresentaram a pélvica muito modificada e conservada na família, sem processos anteriores e posteriores, e com um ponto de sutura entre os basipterígios muito reduzido e posterior; Astroblepidae apresenta uma pélvica muito diferenciada, com longos processos posteriores, lateropterígio em forma de raquete e musculatura muito desenvolvida; e Loricariidae apresentaram lateropterígio em forma de bastão, articulação sincondral entre os basipterígios seguida por suturas ou não, e côndilos bem desenvolvidos para articulação dos raios pélvicos. Nematogenyidae e Trichomycteridae compartilham uma disposição semelhante dos processos anteriores e presença de cartilagem não fusionada entre os basipterígios. Os demais Loricarioidea, ou ‘Loricaroidea avançados’, já apresentam uma articulação com suturas entre os basipterigios. Astroblepidae e Loricariidae compartilham, entre outras estruturas, a presença de lateropterígio, presença de côndilos para articulaçao dos raios pélvicos e articulação sincondral dos basipterigíos seguida por suturas. Algumas características novas são descritas para algumas das famílias (Nematogenyidae, Trichomycteridae e Astroblepidae). O presente estudo veio dar um suporte adicional a atual proposta de relacionamento entre as famílias de Loricarioidea

The genital and anal papillae of Compsura heterura (Characidae: Cheirodontinae): morphological structure and possible role in insemination

The function of the genital and anal papillae for insemination in Compsura heterura is discussed based on the description of their morphologies at different stages of the life cycle and during copulation and spawning. In males and females both the genital and anal papillae are involved in copulation in C. heterura. A pre-anal organ, anterior to the anus and stretched posteriorly, is present in adult males. The openings of the urinary channel and oviduct are separate in females. During copulation, there is an approximation between the female genital and anal papillae which become temporarily juxtaposed, forming a chamber enclosing the opening of the oviduct, which may also function in sperm capture. During spawning, the lateral edges of the female genital papilla are projected anteriorly, acquiring a tubular shape for oviposition.A função das papilas genital e anal na inseminação em Compsura heterura é discutida com base na descrição de suas morfologias em diferentes estágios do ciclo de vida e por ocasião da cópula e desova. Em machos e fêmeas, as papilas genital e anal estão envolvidas na cópula. Um órgão pré-anal, anterior ao ânus e alongado posteriormente, está presente em machos adultos. Fêmeas possuem aberturas urinária e genital separadas. Durante a cópula, ocorre uma aproximação entre as papilas genital e anal femininas, que se justapõem temporariamente, formando uma câmara fechada onde se abre o oviduto, e que serve possivelmente à captura de esperma. Durante a desova, as bordas laterais da papila genital feminina são projetadas anteriormente, adquirindo um formato tubular para ovoposição

Estructura comunitaria de la ictiofauna bentónica del delta del Orinoco y Golfo de Paria (Venezuela), 50 años después de la construcción del dique del caño Manamo

To evaluate the impacts of water flow restriction and regulation caused by the construction of a dike across Manamo Channel, variations in the benthic fish communities were studied in the mouths of three streams or channels (Pedernales, Angostura and Manamo) of the Orinoco River Delta and one stream (Venado) that flows directly into the Gulf of Paria, during one (annual) hydrological cycle. Fishes were sampled with a shrimp trawl net. Of the 78 species collected, five were resident, 12 temporary and 62 occasional. Juvenile phases of all species were collected. Species with greater IVI values were Cathorops sp., Achirus achirus, Stellifer naso and Colomesus psittacus. No significant differences were obtained for the physical and chemical habitat parameters measured: depth, salinity and transparency, nor in the water levels of the streams even in different hydro-phases of the year. Salinity never dropped to zero and no changes in fish species composition were detected. These results lead us to hypothesize that the impacts of the dike constructed in Manamo Channel also extend to other streams of the Orinoco River Delta and even the one studied (Venado) that empties into the Gulf of Paria, where estuarine conditions prevailed during the entire study period of one year, with no observed changed in the hydrological regimen.Con el objetivo de evaluar el efecto de la regulación de las aguas del caño Manamo (por la construcción de un dique), sobre la ictiofauna bentónica de algunos caños del delta del río Orinoco y Golfo de Paria, se estudió la variación de la estructura comunitaria de peces bentónicos en la desembocadura de tres caños del delta del río Orinoco (Pedernales, Angostura y Manamo) y un caño del golfo de Paria (Venado) durante un ciclo hidrológico anual. De las 78 especies colectadas, cinco fueron residentes, 12 temporales y 61 ocasionales; todas registraron ejemplares en estado juvenil. Las especies con mayores valores de IVI fueron Cathorops sp., Achirus achirus, Stellifer naso y Colomesus psittacus. No se observaron diferencias significativas entre los parámetros físico-químicos analizados (profundidad, salinidad y transparencia), ni a nivel de caños, ni entre hidrofases. La salinidad nunca registró valores menores de 4 % y no se observaron cambios en la composición de especies de la comunidad. Con los resultados obtenidos se plantea la hipótesis de que la construcción del dique sobre el caño Manamo en los años 60, afectó el comportamiento natural de este sistema y de otros caños del delta e incluso del golfo de Paria (caño Venado), registrando en las desembocaduras de todos los caños características de un estuario continuo (sin cambios en el régimen hidrológico y salinidad) durante todo el año

Filogenia da subfamília Corydoradinae (Siluriformes: Callichthyidae)

Phylogeny ofthe subfamily Corydoradinae (Siluriformes : Callichthyidae) Corydoradinae, comprising the genera Aspidoras, Brochis and Corydoras, constitutes about 90% of the neotropical catfish family Callichthyidae, a well-defined monophyletic group. A phylogenetic hypothesis within the subfamily is erected with basis on 58 characters, encompassing those proposed by REIS (1993) to define Corydoradinae and its monophyletic units. Monophyly of Corydoradinae is confirmed, as well as for Aspidoras and Brochis. Two major clades compose the subfamily, one with Corydoras species more closely related to Aspidoras than Brochis, and other with species closer to Brochis. These features contrast with the previous hypothesis considering Brochis and all Corydoras species in a monophyletic assemblage and Aspidoras as its sister-group. A clade composed of Aspidoras, C. habrosus, C. paleatus, C. ehrhardti, C. nattereri, (C. hastatus group, C. nanus group, C. elegans, C. undulatus), (C. ellisae, C. ornatus, C. prionotus, C. reticulatus, C. stenocephalus, (C. septentrionalis (C. barbatus group, C. blochi, C. acutus)) is defined by the presence of odontodes on infraorbitals and preopercle, and by an angled free border of opercle. Another clade, (C. flaveolus (C. arcuatus (C. punctatus group (C. triseriatus (C. garbei (C. aeneus (C. eques (C. rabauti group + Brochis)))))))) is defined by the lack of odontodes on opercle, homoplasic with Corydoras hastatus group. Some classification proposals are discussed.CAPESCorydoradinae, incluindo os gêneros Aspidoras, Brochis e Corydoras, constitui cerca de 90% da família de bagres neotropicais Callichthyidae, um grupo monofilético bem definido. Uma hipótese filogenética da subfamília é estabelecida com base em 58 caracteres, abrangendo aqueles propostos por REIS (1993) para definir Corydoradinae e suas unidades monofiléticas. Monofiletismo de Corydoradinae é confirmado, assim como de Aspidoras e Brochis. Dois dados principais compõem a subfamília, um com espécies de Corydoras mais relacionadas com Aspidoras do que com Brochis, e outro com espécies mais relacionadas com Brochis. Estes fatores contrastam com a hipótese prévia que considera Brochis e todas as espécies de Corydoras em um agrupamento monofilético, e Aspidoras como seu grupo-irmão. Um clado composto por Aspidoras, C. habrosus, C. paleatus, C. ehrhardti, C. nattereri, (C. grupo hastatus, C. grupo nanus, C. elegans, C. undulatus), (C. ellisae, C. ornatus, C. prionotus, C. reticulatus, C. stenocephalus, (C. septentrionalis (C. grupo barbatus, C. blochi, C. acutus)) é definido pela presença de odontódeos nos infra-orbitais e pré-opérculo, e pela margem livre do opérculo angulada. Um outro dado, ( C. flaveolus ( C. arcuatus ( C. grupo punctatus (C. triseriatus ( C. garbei (C. aeneus (C. eques (C. grupo rabauti + Brochis)))))))) é definido pela perda de odontódeos no opérculo, homoplásico com Corydoras grupo hastatus. Algumas propostas de classificação são discutidas

Dieta de la Trucha Arcoíris en el área de estudio de tres proyectos mineros en Apurímac, Cuzco y Ancash

Universidad Nacional Agraria La Molina. Facultad de Ciencias. Departamento Académico de BiologíaLa trucha arcoíris Oncorhynchus mykiss es considerada una de las 100 especies invasoras de preocupación mundial debido entre otros aspectos a la predación sobre peces endémicos. En el Perú fue introducida con fines comerciales en la década del 20 y ya es considerada una especie naturalizada por su amplia distribución en la región andina. Algunos especialistas indican que es una especie predadora que se alimenta de peces endémicos y por lo tanto ha afectado dichas poblaciones en nuestro país. Por otro lado, la trucha arcoíris constituye un importante recurso acuícola para comercio interno y externo, así como fuente de proteínas para la población a nivel nacional. En este contexto y con el objetivo de identificar los ítems alimentarios principales de la trucha arcoíris, se analizó información de tres líneas base hidrobiológicas de estudios de impacto ambiental aprobados por el Ministerio de Energía y Minas (MINEM) en las regiones de Apurímac, Cuzco y Ancash. Se procedió a revisar los resultados de contenido estomacal de 224 ejemplares y se calcularon los índices de importancia alimentaria y amplitud trófica para describir su comportamiento alimentario. Como parte de los resultados se registraron principalmente insectos acuáticos de los órdenes Ephemeroptera, Diptera, Coleoptera, Trichoptera; crustáceos de la familia Amphipoda; y gastrópodos en menor porcentaje. También se registraron restos de peces y huevos en el contenido estomacal de 5 ejemplares, lo que demostraría que los peces no son un ítem alimentario principal. Debido que se registró la presencia de peces endémicos de los géneros Astroblepus, Orestias y Trichomycterus, con los que cohabita en las cuencas hidrográficas evaluadas y a que comparten algunos ítems alimentarios en común, se concluye que la relación trófica entre la trucha arcoíris y los peces endémicos es de competencia por el recurso alimentario. Se recomienda realizar una evaluación a nivel de todos los estadíos de madurez de la trucha arcoíris para confirmar estos resultados. Finalmente, debido a la presión de la trucha arcoíris sobre los macroinvertebrados bentónicos, también es recomendable evaluar la posible afectación a esta comunidad biológica y las implicancias en el ciclo de nutrientes de los ambientes acuáticos.The rainbow trout, Oncorhynchus mykiss, is considered one of the 100 invasive species of worldwide concern due to, among other aspects, predation on endemic fish. In Peru, it was introduced for commercial purposes in the 1920s and is already considered a naturalized species due to its wide distribution in the Andean region. Some specialists state that it is a predatory species that feeds on endemic fish and, therefore, has affected these populations in our country. On the other hand, the rainbow trout is an important aquaculture resource for domestic and foreign trade, and it is a protein source of protein for the population at the national level. In this context and aiming to identify the main dietary items of the rainbow trout, three hydrobiological baselines of environmental impact studies approved by the Ministry of Energy and Mines (MINEM) in the regions of Apurimac, Cuzco and Ancash were analyzed. The results of the stomach contents of 224 specimens were examined and the food importance and trophic breadth indexes were calculated to describe their feeding behavior. As part of the results, mainly aquatic insects of the orders Ephemeroptera, Diptera, Coleoptera, Trichoptera; Amphipoda crustaceans; and gastropods in smaller percentages were found. Fish remains and eggs were also found in the stomach contents of 5 specimens, which would prove that fish are not a major food item. Due to the presence of endemic fishes of the genera Astroblepus, Orestias, and Trichomycterus, with which it cohabits in the tested watersheds and because they share some food items in common, it is concluded that the trophic relationship between the rainbow trout and endemic fishes requires full attention for the food resource. An evaluation is recommended at all maturity stages of the rainbow trout to confirm these results. Finally, due to the pressure of the trout rainbows on benthic macroinvertebrates, it is also advisable to evaluate the possible impact on this biological community and the implications for nutrient cycling of water environments

Nuevos casos de leucismo en peces andinos del género Astroblepus

La ictiofauna neotropical es la más diversa del mundo, sin embargo, es también la menos estudiada. Por ejemplo, son escasos los reportes de casos de aberraciones pigmentarias en peces dulceacuícolas, especialmente en especies altoandinas. Este estudio reporta nuevos casos de leucismo en dos especies del género Astroblepus (Siluriformes: Astroblepidae). Los individuos presentaron despigmentación en casi todo el cuerpo, excepto en el iris ocular, pedúnculo caudal, aletas dorsales y caudales. Posiblemente, la endogamia y la contaminación de sus hábitats estén causando estrés en estas poblaciones de peces, potenciado la aparición de esta aberración

Leucismo en Astroblepus ubidiai (Pellegrin 1931)(Siluriformes: Astroblepidae), de la provincia de Imbabura,Ecuador

The leucism is an aberration in pigmentation, resulting from a genetic abnormality and occurs in all vertebrate groups in which the fish are included. In Ecuador it has not reported such anomalies in fish. Is presented for the first time a case of partial leucism in an individual of Andean Catfish (Astroblepidae), observed in a spring located near the Lake San Pablo Canton Otavalo, Imbabura Province, Ecuador.El leucismo es una aberración en la pigmentación, producto de una anomalía genética y se presenta en todos los grupos de vertebrados incluyendo los peces. En Ecuador no se ha reportado este tipo de anomalía en peces. Se presenta por primera vez un caso de leucismo parcial, en un individuo de Astroblepus ubidiai (Astroblepidae), observado en un manantial ubicado cerca del lago San Pablo del cantón Otavalo, cuenca del río Mira, provincia de Imbabura, Ecuador

Ictiofauna del río Manso (Caldas, Colombia)

This paper presents a list of the fishes of the middle and lower part of the Manso River basin, in the department of Caldas, Colombia. It consolidates the results of 33 sampling events at 8 stations distributed in the middle and lower Manso river zone and a tributary stream, in addition to previously available information. A total of 68 species of fish have been recorded for the Manso River. In the period 2012-2014, 55 species were registered, of which 15 are included in the Red Book of Freshwater Fish of Colombia, 12 are species of importance for human consumption and the others that represent biological and ecological interest.Se presenta un listado de los peces de la cuenca media y baja del río Manso (Caldas, Colombia), el cual consolida los resultados de 33 campañas de muestreo que se realizaron  en ocho estaciones distribuidas en la zona media y baja del río y una quebrada tributaria, además de la información previamente existente. En total se han registrado para el río Manso 68 especies de peces. En el periodo 2012-2014 se registraron 55 especies, de las cuales 15 están incluidas en el Libro Rojo de Peces de Agua Dulce de Colombia, 12 son especies de importancia para consumo humano y las demás representan interés biológico y ecológico

Conservation threats and future prospects for the freshwater fishes of Ecuador: A hotspot of Neotropical fish diversity

Freshwater fish communities in Ecuador exhibit some of the highest levels of diversity and endemism in the Neotropics. Unfortunately, aquatic ecosystems in the country are under serious threat and conditions are deteriorating. In 2018–19, the government of Ecuador sponsored a series of workshops to examine the conservation status of Ecuador''s freshwater fishes. Concerns were identified for 35 species, most of which are native to the Amazon region, and overfishing of Amazonian pimelodid catfishes emerged as a major issue. However, much of the information needed to make decisions across fish groups and regions was not available, hindering the process and highlighting the need for a review of the conservation threats to Ecuador''s freshwater fishes. Here, we review how the physical alteration of rivers, deforestation, wetland and floodplain degradation, agricultural and urban water pollution, mining, oil extraction, dams, overfishing, introduced species and climate change are affecting freshwater fishes in Ecuador. Although many of these factors affect fishes throughout the Neotropics, the lack of data on Ecuadorian fish communities is staggering and highlights the urgent need for more research. We also make recommendations, including the need for proper enforcement of existing environmental laws, restoration of degraded aquatic ecosystems, establishment of a national monitoring system for freshwater ecosystems, investment in research to fill gaps in knowledge, and encouragement of public engagement in citizen science and conservation efforts. Freshwater fishes are an important component of the cultural and biological legacy of the Ecuadorian people. Conserving them for future generations is critical. © 2021 The Authors. Journal of Fish Biology published by John Wiley & Sons Ltd on behalf of Fisheries Society of the British Isles