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This work describes the length-weight relationship (LWR) of 37 fish species from the Taquari River, one of the tributaries of the Jurumirim Reservoir in the high Paranapanema Basin, São Paulo, Brazil. Information was not yet available in FishBase on LWRs of 22 of the fish species and maximum weights (Wt) of 24 of the fish species. New maximum standard lengths are presented for nine species as well as weights for two fish species. † In Memoriam

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 Brazilian aquaculture shows problems of ecological impact due to the lack of appropriated planning and legislation to the aquatic biota. The non‐recognition of sustainable census incorporated in its environmental politics reflects in an archaic and unsustainable management, with the following characters: a non‐specific approach for technical management, the indiscriminate use of interspecific hybrids and non‐native species and the lack of skilled labour. The potential impact on native species and the introduction of pathogens are the main negative effects on aquatic biota. This way, the aim of this article is to elucidate the conflicts of interests and ecological effects of fish aquaculture in Brazil, besides providing good practices and sustainable alternatives for management.

Knowledge of ichthyoplankton dynamics is extremely important for conservation management as it can provide information about preferential spawning sites, reproductive period, migratory routes and recruitment success, which can be used to guide management and conservation efforts. However, identification of the eggs and larvae of Neotropical freshwater fish is a difficult task. DNA barcodes have emerged as an alternative and highly accurate approach for species identification, but DNA barcoding can be time-consuming and costly. To solve this problem, we aimed to develop a simple protocol based on DNA metabarcoding, to investigate whether it is possible to detect and quantify all species present in a pool of organisms. To do this, 230 larvae were cut in half, one half was sequenced by the Sanger technique and the other half was used to compose six arrays with a pool of larvae that were sequenced using a next-generation technique (NGS). The results of the Sanger sequencing allowed the identification of almost all larvae at species level, and the results from NGS showed high accuracy in species detection, ranging from 83% to 100%, with an average of 95% in all samples. No false positives were detected. The frequency of organisms in the two methods was positively correlated (Pearson), with low variation among species. In conclusion, this protocol represents a considerable advance in ichthyoplankton studies, allowing a rapid, cost-effective, quali-quantitative approach that improves the accuracy of identification.