Results: 293

Population genetics of three threatened catfish species in heterogeneous environments of the Cauca River, Colombia

Neotrop. ichthyol; 19 (1), 2021
Neotropical catfishes Ageneiosus pardalis, Pimelodus grosskopfii and Sorubim cuspicaudus are migratory fishes of commercial importance that exhibit decreasing populations due to overfishing and other anthropic interventions. This study used species-specific microsatellite loci to test the hypothesis that...

Adjustments in population and reproductive dynamics of native and non-native congeneric species during 26 years after invasion

Neotrop. ichthyol; 19 (1), 2021
We aimed to improve the understanding of the establishment of Serrasalmus marginatus (non-native), which was followed by a decrease in the abundance of Serrasalmus maculatus (native) in the upper Paraná River floodplain. We estimated age, mortality rate, length and age at first maturity and variations i...

Centesimal composition and meat yield of Hoplias malabaricus: association with intestinal parasites

Abstract Hoplias malabaricus is a non-migratory fish commonly found in the Mogi Guaçu River basin, mainly feeding on fish, small crustaceans and insects. It forms part of the diet for humans, birds and some mammals. This fish has great nutritional value, with both good quality and good quantities of ess...

Functional responses of stream fish communities to rural and urban land uses

Neotrop. ichthyol; 19 (3), 2021
We tested the effects of ruralization and urbanization on the functional diversity indices and the composition of functional traits of Neotropical stream fish communities. The study was carried out in 24 streams of the Pirapó, Piquiri, Paraná III and Iguassu river basins. Land use in the watershed was ...

A cascade of dams affects fish spatial distributions and functional groups of local assemblages in a subtropical river

Neotrop. ichthyol; 19 (3), 2021
Dams reduce the longitudinal connectivity of rivers and thereby disrupt fish migration and the spatial distribution of species, impacts that remain poorly studied for some Neotropical rivers from mega-diverse basins. We investigated the spatial distribution of fish species with different trophic and move...

Taxonomic and functional turnover of Amazonian stream fish assemblages is determined by deforestation history and environmental variables at multiple scales

Neotrop. ichthyol; 19 (3), 2021
High rates of deforestation, either in the past or the present, affect many of the ecological processes in streams. Integrating deforestation history and the current landscape structure enhances the evaluation of ecological effects of land-use change. This is especially true when contemporary landscape c...

Diversity of metazoan parasites in fish Triportheus angulatus and Triportheus auritus living in sympatry in the Brazilian Amazon

Abstract The aim of this study was to compare the diversity and community structure of metazoan parasites in sympatric populations of Triportheus angulatus and Triportheus auritus in the Jari River basin, in the eastern Brazilian Amazon. All the specimens of T. angulatus and T. auritus examined were infe...

Diversity and community ecology of metazoan parasites in Pimelodus ornatus (Siluriformes: Pimelodidae) from the Amazonas River in Brazil

Abstract The present study investigated the metazoan parasite community in Pimelodus ornatus from the Amazon River, in the state of Amapá (Brazil). Of 71 fish examined, 70.4% were parasitized by Demidospermus sp. (Monogenea), Cucullanus pinnai, Procamallanus (Spirocamallanus) inopinatus and Contracaecum...

Land-use changes affect the functional structure of stream fish assemblages in the Brazilian Savanna

Neotrop. ichthyol; 19 (3), 2021
We investigated the mechanisms involved in the relationship between land-use changes and aquatic biodiversity, using stream fish assemblages of the Brazilian Savanna (i.e., Cerrado) as a study model. We tested the prediction that landscape degradation would decrease environmental heterogeneity and change...