Interspecific hybridization can offer advantages in fish aquaculture by enhancing traits like growth rate and disease resistance. However, improper management can result in heterogeneous breeding stocks, which pose risks if hybrids interbreed with native populations. This can lead to loss of genetic diversity and alterations in population structure. This study aimed to evaluate the prevalence of hybridization within the Brazil...

The shark Squalus albicaudus, categorized by the International Union for Conservation of Nature red list as Data Deficient due to lack of minimal information for classification, is distributed throughout the Brazilian coast. High pressures such as overfishing and anthropic activities, as well as certain biological characteristics, including k strategists, comprise influential shark stocks reduction agents. However, genetic div...

Heptapteridae is composed of 228 valid species allocated in 24 genera, making it the most diverse family within superfamily Pimelodoidea, a clade endemic to the Neotropical freshwaters. Heptapterids are widely distributed from southern Mexico to the Pampas of Argentina and occupy a variety of habitats generally in small‐ to medium‐sized rivers. To evaluate the phylogenetic relationships of Heptapteridae, we used a matrix with...

The Neotropical catfish genus Kronichthys contains three species distributed along coastal rivers of southern and southeastern Brazil. Although phylogenetic hypotheses are available, the molecular and morphological diversity and species boundaries within the genus remain unexplored. In this study, the authors generated mitochondrial data for 90 specimens combined with morphometric and meristic data to investigate species diver...

Brazil is a megadiverse country and is participant of fundamental environmental agreements for biodiversity conservation. However, the internal politics and the cultures that affect negatively the ecological integrity in Brazilian freshwater need to be improved on the condition of sustainable management. Scientific community, the government and stakeholders are in constant conflicts of goals. Meanwhile, the current model for B...

Neotropical darters of the genus Characidium have a complex systematic history with several examples of sympatry throughout their distribution range in Neotropical freshwaters. Although various species within the genus have been used as models to investigate chromosomal evolution and biogeography, species boundaries and relationships still remain uncertain. Here, we use mitochondrial DNA sequences to perform species delimitati...