Results: 80

Morphological aspects in the ontogeny of Salminus hilarii Valenciennes, 1850 (Ostaryophysi: Characidae)

Braz. j. biol; 76 (4), 2016
Abstract This study compared various morphological characteristics of S. hilarii, in order to verify possible variations over the life of the fish. It was used individuals collected from the Tietê river basin (sub-basins of Sorocaba, Jacaré Pepira and Corumbataí rivers) and from the Rio Grande basin (...

Communities of parasite metazoans in Piaractus brachypomus (Pisces, Serrasalmidae) in the lower Amazon River (Brazil)

Abstract The aim of this study was to investigate the component community of parasite metazoans of Piaractus brachypomus in the lower Amazon River, northern Brazil. From 34 necropsied fish, 27,384 metazoan parasites were collected, such as Anacanthorus spathulatus, Mymarothecium viatorum and Notozotheciu...

Karyotypic diversity among three species of the genus Astyanax (Characiformes: Characidae)

Braz. j. biol; 76 (2), 2016
Abstract The group Incertae sedis within the Characidae family currently includes 88 genera, previously included in the subfamily Tetragonopterinae. Among them is the genus Astyanax comprising a group of species with similar morphology and widely distributed in the Neotropics. Thus, the present study aim...

Population structure and reproductive biology of Astyanax gymnodontus(Characiformes: Characidae), a poorly known endemic fish of the Iguaçu River basin, Brazil

Rev. biol. trop; 64 (1), 2016
AbstractSuccess in fish breeding depends on reproduction intensity, periodicity and the place where it occurs. Information about fish species reproduction is important to assist managers, and to determine conservation and management strategies. The fish assemblage of the Iguaçu River basin is already kn...

Densidade de estocagem na produção de juvenis de duas espécies de lambaris em sistema de recirculação

The aim of this study was to evaluate the stocking density for juveniles for two different species of characins (Astyanax bimaculatus and A. scabripinnis) in a recirculation system. An experiment was carried out with each type in which twelve tanks in each experiment were divided into four treatments (0....

Molecular variants in populations of Bryconamericus aff. iheringii (Characiformes, Characidae) in the upper Paraná river basin

Acta sci., Biol. sci; 35 (2), 2013
There are evidences that Bryconamericus aff. iheringii represents a species complex. DNA molecular markers have been effective in studies on phylogeny, taxonomy, and identification of cryptic species. In this study, partial sequences of genes of ATPase 6 and 8 were used to assess genetic diversity within...

Nucleotide diversity of Hemigrammus cf. marginatus (Characiformes, Characidae) in the upper Paraná river floodplain

Acta sci., Biol. sci; 34 (3), 2012
Characidae is the largest and more diversified family from Characiformes and presents several classification problems, with several genera currently allocated as incertae sedis, such as the genus Hemigrammus. The upper Paraná river floodplain is an environment with high fish diversity. There is at least...

Velocidade crítica de natação (Ucrit) de matrinxã (Brycon amazonicus) após exposição à hipoxia

Acta amaz; 40 (4), 2010
A primeira resposta ao estresse é a fuga, que depende do desempenho natatório e de ajustes fisiológicos. Este estudo investigou a velocidade crítica de natação (Ucrit) de matrinxã após exposição à hipoxia. Para isso, os peixes foram expostos à hipoxia, sendo uma parte do grupo analisada antes...

Dermal lip protuberances associated with aquatic surface respiration in juveniles of the piscivorous characid Salminus brasiliensis (Actinopterygii: Characidae)

Neotrop. ichthyol; 7 (3), 2009
Some South American freshwater fishes can improve their capability of aquatic surface respiration (ASR) by developing dermal lip protuberances in the lower jaw. This adaptation was thought to be limited to omnivorous or herbivorous fishes. The present work provides the first evidence that juveniles of a ...

Temporal and ontogenetic variations in feeding habits of Hollandichthys multifasciatus (Teleostei: Characidae) in coastal Atlantic rainforest streams, southern Brazil

Neotrop. ichthyol; 7 (3), 2009
Feeding habits of the characin Hollandichthys multifasciatus were investigated. Samplings were made between March 2004 and February 2005 in two black water streams of the coastal Atlantic rainforest in southern Brazil. The diet, evaluated by qualitative and quantitative methods, included aquatic and terr...