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Global change drivers including eutrophication, hydrological disturbance, climate change, chemical pollution, overexploitation, invasive species, and land-use change are affecting the function and ...

The Amazon Basin is an unquestionable biodiversity hotspot, containing the highest freshwater biodiversity on earth and facing off a recent increase in anthropogenic threats. The current knowledge on the spatial distribution of the freshwater fish species is greatly deficient in this basin, preventing a comprehensive understanding of this hyper-diverse ecosystem as a whole. Filling this gap was the priority of a transnational collaborative project, i.e. the AmazonFish project - https://www.amazon-fish.com/. Relying on the outputs of this project, we provide the most complete fish species distribution records covering the whole Amazon drainage. The database, including 2,406 validated freshwater native fish species, 232,936 georeferenced records, results from an extensive survey of species distribution including 590 different sources (e.g. published articles, grey literature, online biodiversity databases and scientific collections from museums and universities worldwide) and field expeditions conducted during the project. This database, delivered at both georeferenced localities (21,500 localities) and sub-drainages grains (144 units), represents a highly valuable source of information for further studies on freshwater fish biodiversity, biogeography and conservation., Measurement(s)Diversity • Fish • spatial patternTechnology Type(s)digital curationFactor Type(s)geographic locationSample Characteristic - OrganismfishSample Characteristic - Environmentdrainage basinSample Characteristic - LocationAmazon Basin Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.11920800

The presence of striped catfish ( Pangasianodon hypophthalmus ) in inland waters of Colombia is recorded. This Asian species was recently brought into the country illegally. Although Colombia´s environmental legislation does not allow the introduction of alien species, in August 2015 artisanal fishermen captured a specimen of striped catfish at the Rio Carare, a tributary of the middle basin of the Rio Magdalena. To date eight confirmed records of this species exist in the same region. The striped catfish must be considered as an exotic species in Colombia, and the consequences of this introduction are uncertain, both for aquatic ecosystems and for the regional fish fauna, with many important fishery species in the basin.

For the first time, the catalog of type specimens of ICN-MHN is presented with high resolution photographs. The catalog lists 87 species in 161 lots and includes 41 holotypes, 3 neotypes, and 117 lots of paratypes. Some doubts remain about type specimens of some species described by Miles and Dahl that were supposedly deposited at ICN-MHN. The history of the collection is reconstructed and valuable specimens once considered lost or destroyed have been rediscovered. The botanical and zoological collections of the ICN can be consulted online (http://www.biovirtual.unal.edu.co).

Small, oligotrophic Amazonian streams support an extremely rich fish fauna. The aim of the current study was to elucidate the relationship between diet and morphology in fishes from an Amazonian terra firme stream in the Colombian Amazon River basin near the city of Leticia. Fish specimens were collected from two locations at the Yahuarcaca terra firme stream. All fish species selected in the morphological analyses were used in the dietary analyses. We analyzed 10–60 adult individuals per species based on availability. Morphology and diet were correlated by direct observation (description) of morphological structures and food items found in gut. Only morphological variables presumed to be associated with prey capture and feeding were recorded for each individual. Species diets were classified into six food categories based on stomach content analysis. By comparing morphological characteristics, and dietary data, it was possible to find a relationship between structures and feeding habits. Morphological and dietary specializations were found among some fishes inhabiting the examined stream. Internal morphological characteristics such as gill rakers, pharyngeal teeth, pyloric caeca and stomach form should be used more often in ecomorphological studies because they are directly associated with resource utilization and linked to feeding habits.

Pseudoplatystoma Magdaleniatum is one of the most representative fish species from the Magdalena river basin in Colombia. This endemic catfish is highly valuable from the economic and environmental perspectives. Nevertheless, it is currently under threat because of the indiscriminate fishery and the degradation of their ecological niche. Strategies for conservation require a detailed individual description. Traditional characterization methods are invasive and time expensive. Here we introduce a novel automatic method to segment and describe the characteristic spot and stripe skin pattern of this specie. The method was evaluated on a photographic database of 50 individuals, which characteristic skin patterns were manually segmented by a trained expert. The proposed approach provides precise skin pattern segmentations and informative geometrical features of these patterns.

A multigear sampling method to quantify fish richness and abundance in Amazonian Terra firme streams was assessed. This method is based on the four-pass removal method using the combined application of different nets. The efficiency of the method was explored over 10 replicated sites along three streams over day, night and seasons. Use of four successive passes allowed both abundant and rare species to be collected and the abundance of common species to be estimated. On average, a high proportion (41%) of rare species was collected per sample (only one or two individuals) after four fishing passes. The efficiency of the sampling method to detect species richness per sample between successive passes was estimated using an autosimilarity approach. Although species richness and abundance increased with successive passes, no major differences were obtained between the third and fourth pass. A single pass considerably underestimated the richness and abundance of species in these type of streams, and night sampling also increased beta-diversity by at least 20%. Abundance estimates demonstrated high efficiency with an overall sampling error of only 8 and 11% for samples and single species, respectively. Capture efficiency differed among fish species exhibiting different ecological traits and showed significant differences among seasons for total samples. Results supported the robustness of the method and its suitability to quantify fish richness and abundance in small, wadeable Amazonian Terra firme streams inhabited by highly diverse fish assemblages. © 2014 John Wiley & Sons Ltd.

Se evaluó la trazabilidad de los registros de mamíferos informados en el marco del otorgamiento de licencias ambientales en el sector de hidrocarburos en Colombia, en una muestra de 43 proyectos con licencias otorgadas en el 2014. El análisis se hizo mediante un método propuesto por los autores, el cual se fundamenta en el concepto de voucher biológico. Los resultados demostraron la falta de evidencia biológica verificable, que permita poner a prueba o revisar la identidad y características de la fauna de mamíferos reportada. Bajo estas circunstancias, la información pierde confiabilidad, lo cual limita la posibilidad de usarla, revisarla o reinterpretarla en investigaciones futuras. Si esta condición resulta ser un rasgo común en las caracterizaciones de la fauna que se presentan para el otorgamiento de licencias a los proyectos, ello implicaría que se está desperdiciando una oportunidad única para el conocimiento de la diversidad biológica del país, y que las decisiones sobre la viabilidad ambiental de los proyectos de hidrocarburos estarían respaldadas por estudios de mamíferos con un grado significativo de incertidumbre, en cuanto a la identidad y las características de los taxones registrados. We evaluated the traceability of mammalian records reported in the framework of environmental licensing in the oil sector in Colombia based on a sample of 43 projects licensed during 2014. Our analysis was done using the method we have proposed based on the concept of biological voucher. Our results showed a lack of the verifiable biological evidence that allows to test or review the identity and features of reported mammals. Under these circumstances, the information loses reliability and its eventual use, review or reinterpretation in future research work is restricted. If this condition proves to be a common feature in the studies of fauna presented for projects licensing, it would imply that a unique opportunity to increase the knowledge on the country’s biological diversity is being wasted, and that decision-making on environmental viability of oil projects is supported on mammalian studies with a significant degree of uncertainty in terms of the identity and characteristics of the recorded taxa.

Con base en imágenes de microscopía electrónica de barrido tridimensional (SEM) de alta resolución de Paravandellia phaneronema (Miles 1943), especie de ictioparásito endémica de Colombia, se describieron y analizaron las estructuras morfológicas superficiales desarrolladas en su proceso evolutivo de adaptación a la forma de vida hematófaga. La atención se enfocó en los aspectos emergentes de la función de estas adaptaciones y en los mecanismos que estos parásitos de la subfamilia Vandellinae han utilizado para localizar con precisión su pez huésped y fijarse en sus branquias. Se concluyó que detectan al huésped utilizando los neuromastos, receptores mecánicos del sistema de poros cefálicos y de la línea lateral, y no a través de la recepción química de productos del nitrógeno catabólico, como se ha sugerido. © 2018. Acad. Colomb. Cienc. Ex. Fis. Nat.

– The objective of this study was to quantify fish species diversity in Terra firme streams of the Rio Amazonas drainage. Fish diversity was quantified as the number of species collected or species richness in two sites of Yahuarcaca stream, a typical, first order tributary of the central Rio Amazonas near Leticia (Colombia). The extremely high species richness recorded, 131 and 133 for the two study sites for a total of 171 species, was primarily due to species of low abundance (rare species) mostly with adults

The Magdalena River Basin is the most important region of Colombia in terms of development and economy. About 80% of its population lives in this basin and traditionally its waters have produced more than 60% of fish consumed in the country. Nonetheless, from a production of nearly 80,000 ton yr− 1 in the 1970s, currently those fisheries produce only one tenth of that amount. This paper analyzes the different reasons of this collapse, and concludes that the causes are social, due to over fishing by landless displaced peasants trying to survive as fishermen.

Astroblepid species inhabit the Andean Cordilleras in South America. Their habitat has undergone a rapid transformation to the unimaginable levels of degradation since ancient times. State of knowledge on the habitat perturbation and the concomitant extirpation of endemic astroblepid species is scarce. The Andes Cordilleras are characterized by fertile soil and as a result of that, vast regions are transformed for agriculture and pasture for cattle. These processes require the use of water obtained from creeks and springs that causes remarkable changes of the natural configuration of these water systems and the disappearance of the fish fauna together with the zooplankton and aquatic flora. Despite these human actions, some species of Astroblepus may have the ability to respond to the rapid habitat transformation enabling them to survive. In this paper we will discuss the incidence of habitat perturbation in a localized stream segment on the presence of Astroblepus mariae. Las especies del género Astroblepus habitan en la cordillera de los Andes en Suramérica. Desde tiempos remotos sus hábitats han sufrido transformaciones rápidas que han resultado en niveles inimaginables de degradación. Sin embargo, es escaso el conocimiento sobre las perturbaciones de hábitat y la desaparición simultánea de especiesendémicas del género Astroblepus . En general, los suelos de la cordillera de los Andes se caracterizan por su fertilidad, por lo que extensas regiones han sido transformadas para la agricultura y el pastoreo de ganado, procesos que requieren del uso de agua proveniente de arroyos y manantiales, lo cual conlleva cambios notables en la configuración natural de estos sistemas de agua, así como la desaparición de peces, zooplancton y flora acuática.A pesar de estas acciones antrópicas, algunas especies de Astroblepusparecen tener la capacidad de responderrápidamente a las transformaciones del hábitat y de sobrevivir en estas condiciones Se discute aquí la incidencia de la perturbación del hábitat en un tramo de arroyo con presencia de Astroblepus mariae.

A new species of Farlowella is described from El Carmen de Chucuri in the Departamento de Santander, western flank of the Cordillera Oriental, rio Magdalena Basin, Colombia. Farlowella yarigui n. sp. differs from its congeners in lateral body plate morphology, abdominal cover, cephalic hypertrophied odontodes, and details of coloration. This is the first verifiable record of the genus in the Magdalena drainage. Aspects of natural history and implications of this finding are provided concerning the state of knowledge of the fishes of the rio Magdalena Basin. Previous records of Farlowella gracilis in the rio Cauca basin are examined and herein considered erroneous, rendering the new species the only representative of the genus in the Magdalena-Cauca system. A key to species of Farlowella from Colombia is provided.