Primer registro de Lepidosiren paradoxa Fitzinger, 1837 en la cuenca del Orinoco (PNN El Tuparro, Vichada, Colombia)

The South American dipnoans are represented by a single species (Lepidosiren paradoxa) belonging to the Lepidosirenidae family (Nelson, 1994). These fishes are related to the African lungfish family Protopteridae that belong to the same order (Lepidosireniformes), and share with them a number of morphological characteristics and behavior. They tend to be considered authentic living fossils, as they are one evolutionary step between fish and amphibians. The Lepidosirenids have elongated bodies that may measure up to 1, 25 m; their fins are vascularized filaments; they have unpaired vomerine teeth, and lack bones in their cheeks, as well as in the premaxila and maxila (Arratia 2003).Los dipnoos suramericanos están representados por la familia Lepidosirenidae con una única especie, Lepidosiren paradoxa (Nelson 1994). Estos peces son emparentados con la familia Protopteridae, peces pulmonados africanos, que pertenecen al mismo orden (Lepidosireniformes), con los que comparten características morfológicas y hábitos en su comportamiento. Son considerados auténticos fósiles vivientes al ser un escalón evolutivo entre los peces y los anfibios. Los lepidosirenidos presentan cuerpos alargados que pueden alcanzar hasta 1,25 m de longitud; sus aletas son filamentos vacularizados, en la boca presentan dientes vomerianos impares y carecen de huesos en las mejillas al igual que la premaxila y maxila (Arratia 2003)

Effects of aquatic vegetation on the spatial distribution of grundulus bogotensis, humboldt 1821 (characiformes: characidae)

G. bogotensis has a geographic distribution restricted to the Colombian Cundiboyacenseplateau, it is listed as near threatened, and research on its autoecology is scarce. Threecollections were made in 2006 in the Fúquene Lake, Cundinamarca, Colombia (5°27’ 55’’ N, 75° 46’ 19’’ W) to describe the habitats occupied by G. bogotensis and todetermine its vertical and horizontal distribution. Three sampling zones were selectedaccording to the type of dominant macrophyte (Eichornia crassipes, Schoenoplectussp. and Egeria densa). In each sampling zone two different cylindrical sampling traps(cloth and PVC) were placed at three depths: surface, mid-depth and bottom. Threereplicates were used for each depth and type of trap. Traps were exposed for 24 hoursand checked every 6 hours. In addition to the traps, sampling by electrofishing wasconducted in each sampling zone during every month. To characterize the study area,physical and chemical variables were analyzed and the structure of phytoplankton,zooplankton, periphyton, and macroinvertebrate communities was studied. Resultsshowed spatial differences on G. bogotensis habitat occupation and differences incaptures at each depth, which depend on the dominant type of aquatic vegetationand size of individual. We conclude that only cylindrical cloth traps are suitable toconduct population studies of G. bogotensi

Peces del piedemonte del departamento de Casanare, Colombia

Se presenta un listado de especies de peces para el área del piedemonte del departamento del Casanare, región de la Orinoquia en Colombia. El listado es resultado de colectas en campo realizadas entre 2006 y 2009 en 52 puntos de muestreo en los principales ríos de la región, revisión de material depositado en colecciones y revisión de literatura disponible. Se registran 168 especies pertenecientes a seis órdenes, 27 familias y 93 géneros. Del total de especies, nueve son nuevos registros para la cuenca del río Orinoco en Colombia. El río que presenta el mayor número de registros de especies es el Cusiana (115), seguido de los ríos Cravo Sur (96), Pauto (58), Túa (49), Upía (45), Casanare (15) y Guachiría (10)

A database of freshwater fish species of the Amazon Basin

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

Especies de peces gymnotiformes (Gymnotiformes, Teleostei) de Colombia

Neotropical electric fishes (Teleostei, Gymnotiformes), also called American knifefishes, are an important component of the nocturnal ichthyological fauna in Middle and South America. As with many Neotropical fishes, the actual diversity of Gymnotiforms has only come to be appreciated in recent years. The present number of Gymnotiforms is much higher than was previously recognized, with 131 valid species currently reported in the literature and at least 39 additional and undescribed species are currently known in museum collections (Albert unpubl. obs.

Peces de la zona hidrogeográfica de la Amazonía, Colombia

La cuenca del Amazonas cubre alrededor de 6.8 millones de km2 en la cual el río Amazonas, su mayor tributario, tiene una longitud aproximada de 6000 – 7800 km. Gran parte de la cuenca Amazónica recibe de 1500 – 2500 mm de precipitación media anual y la descarga estimada para el río Amazonas ha sido calculada en 214 millones de litros por segundo en promedio (Goulding et al. 2003). A Colombia le corresponde un 8% (420.000 km2) del área de la cuenca, ocupando cerca del 31% del territorio nacional (Bogotá-Gregory & Maldonado-Ocampo 2005). La zona hidrogeográfica de la Amazonia en Colombia recibe el aporte de ocho cuencas y 78 subcuencas. Las principales cuencas corresponden a los ríos Guainía-Negro, Vaupes, Apaporis, Caquetá, Putumayo y Amazonas (IDEAM 2004

Apteronotus milesi, new species of ghost knifefish (Gymnotiformes: Apteronotidae) from the Cauca River, with a key to apteronotids from the Magdalena-Cauca basin, Colombia

Aperonotus milesi, new species, is described from the Quebrada Cristales, Rio Chanco and Rio La Vieja, tributaries of the upper Cauca River Basin, in Colombia. It can be distinguished from its congeners in the trans-Andean region by a light brown body coloration, with fine black pigment spots distributed over the integument; low number of anal-fin rays; and presence of secondary sexual dimorphism. The description of this new species brings the number of the trans-Andean apteronotids to nine. A dichotomous key to Apteronotidae from the Magdalena-Cauca hydrographic region is provided. © 2005 by Verlag Dr. Friedrich Pfeil