Biochemical evidence of a possible new species of Neoplecostomus (Teleostei : Loricariidae) from the upper Rio Parana basin, Brazil

Neoplecostomus paranensis Langeam, 1990, from the upper Rio Parana, is the only Neoplecostomus species described in this basin and is distinguished from its congeners by the lack or reduction of the adipose fin. Neoplecostomus specimens with a normal and always present adipose fin were caught in the Rio Corumba, upper Rio Parana basin. In the present study two samples of populations, one from a tributary of Rio Paranapanema (identified as a typical N. paranensis) and the other from the Rio Corumba were compared through allozyme electrophoresis. Six diagnostic loci were found, Acp-A, Adh-A, Est-A, Gpi-A, Ldh-A and Ldh-B. In addition, the locus Gpi-B showed significant differences between allelic frequencies for the two samples. Nei's genetic identity between the populations was 0.731. The expressive genetic divergence together with the presence of an adipose fin show that the sample from the Rio Corumba is distinct from N. paranensis and probably represents a new species. (C) 2003 Published by Elsevier Ltd.

A new Moenkhausia Eigenmann, 1903 (Ostariophysi: Characiformes) from Chapada Diamantina, rio Paraguaçu Basin, Bahia, Northeastern Brazil

Moenkhausia diamantina, nova espécie, é descrita de tributário do rio Paraguaçu, BA, nordeste do Brasil. Esta espécie é distinguida das demais congêneres por caracteres relacionados ao padrão de coloração do corpo, pela presença de escamas na linha mediana pré-dorsal e número de raios da nadadeira anal.

Deep barcode divergence in Brazilian freshwater fishes: the case of the Sao Francisco River basin

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

DNA barcoding reveals hidden diversity in the Neotropical freshwater fish Piabina argentea (Characiformes: Characidae) from the Upper Parana Basin of Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Description of a new species of Pareiorhina (Siluriformes: Neoplecostominae) from Rio Sao Francisco basin

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Genetic differentiation among ten populations of the genus Neoplecostomus (Teleostei: Loricariidae) from the upper Parana River basin

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A new species of Hyphessobrycon (Characiformes : Characidae) from rio Portuguesa, rio Orinoco basin, Venezuela

A new species of Hyphessobrycon is described from tributaries of the rio Portuguesa, rio Orinoco Basin, Venezuela. The new species is diagnosed from congeners by the presence of two large hooks on each side of the anal fin in adult males ( processes of last unbranched and first branched anal-fin rays), distal third of caudal-fin black except for its distal tips ( which are hyaline), anal-fin rays v, 19-21, and dorsal-fin rays ii, 8. Comments on its generic status and putative relationships are provided.

Genetic variability of two populations of Pseudoplatystoma reticulatum from the Upper Paraguay River Basin

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Length-weight relationships for 20 species collected in the Jurumirim reservoir (Paranapanema Basin, Brazil)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A new species of Ctenobrycon Eigenmann, 1908 (Characiformes: Characidae) from the rio Orinoco basin, Venezuela

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

DNA barcodes discriminate freshwater fishes from the Paraiba do Sul River Basin, São Paulo, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influence of cage fish farming on the diet of dominant fish species of a Brazilian reservoir (Tiete River, High Parana River basin)

The cage farming of aquatic organisms was initiated 50 years ago, and was introduced to Brazil in the 1990's. In these systems, there is an input of organic matter from ration that is not totally used by the cage fishes, becoming available for the organisms of adjacent biota, including fish fauna. The aim of this work is to evaluate the interference in the diet of three dominant fish species (Plagioscion squamosissimus Heckel, 1840, Astyanax altiparanae Garutti and Britski, 2000 and Metynnis maculatus Kner, 1858) associated with ish cage farming. For determination of the diet, the Alimentary Index (AI) was used. In both stretches (around cage farm and control), P. squamosissimus selected aquatic insects, while A. altiparanae preferred terrestrial insects and M. maculatus eats ration remains. Diferences in abundance of these feeding resources found of the stomach content were observed among the two stretches. Thus, the small alterations in the diets of P. squamosissimus and A. altiparanae, indicate that cage farming can change the diet of resident species in reservoirs. This practice also influences the population structure of fish species, since higher middle standard lengths were found in A. altiparanae and P. squamosissimus populations resident around cage farms, in relation to the control stretch.

Cytogenetic analysis in the incertae sedis species Astyanax altiparanae Garutti and Britzki, 2000 and Hyphessobrycon eques Steindachner, 1882 (Characiformes, Characidae) from the upper Parana river basin

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Ichthyofaunal survey of the Riacho Goulart, tributary of the Tiete River (upper Parana basin).

Fishes assessed in the present study were collected in the Riacho Goulart, a small tributary of Tiete River, upper Parana basin. In order to sample different habitats, four collection sites were selected. A total of 1,241 individuals belonging to 30 species, 15 families, and six orders were captured. The list of fish species presented herein is important for the knowledge of the biodiversity of low Tiete basin.

TAXONOMIC POSITION of GUIRATINGIA MENDESI (MEGADESMIDAE) and THE EVOLUTION of PERMIAN ENDEMIC BIVALVE FAUNA of THE PARANA BASIN, BRAZIL

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)