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Aim: The disjunct distributions of freshwater organisms along coastal drainages are usually explained by palaeodrainages formed during sea‐level retreats that connected currently isolated basins, or by river capture from tectonic adjustments between adjoining watersheds. We evaluate the relative importance of these events on the genetic variation of freshwater fishes inhabiting the Serra do Mar in eastern Brazil, a region with steep mountains and pronounced bays. Location: Coastal river drainages in southeastern Brazil. Taxon: Catfishes of the Trichomycterus alternatus group. Methods: We tested the effects of palaeolandscape connections (GIS‐reconstructed palaeodrainages and putative river captures) on the genetic structure (mitochondrial and nuclear markers) of T. alternatus from 15 drainages using phylogenetic reconstructions, lineage delimitation methods and analyses of molecular variance. Results: Trichomycterus alternatus is monophyletic and comprised of three main lineages: two restricted to the basin at its northernmost distribution and another broadly distributed to the south. In the latter, seven major cytb clades were geographically compatible with the eight palaeodrainages, with three incongruences matching river captures previously described for the Guanabara Bay (GB). Shared haplotypes among isolated rivers flowing into GB provide the first molecular evidence of the 'Rio de Janeiro' palaeoriver. Main conclusions: Dispersal via palaeorivers is an important process, but it is not enough to recover the most recent dispersive events. Therefore, integrating both palaeo‐riverine configuration (GIS‐based) and localized river captures (geological studies) is crucial to reveal the role of past geological and climatic events on the distribution of freshwater organisms. Taken together, these two factors significantly explained a high portion T. alternatus genetic structure along coastal drainages, revealing a palaeolandscape scenario that may have been used by other freshwater Atlantic Forest taxa. [ABSTRACT FROM AUTHOR]

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Copyright of Revista Eletrônica de Enfermagem is the property of Revista Eletronica de Enfermagem and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fishing has a major impact on the biodiversity of elasmobranchs, a diverse and ancient group of fish. The illegal trade of products derived from endangered species is widespread and many times concealed by both deliberate and inadvertent mislabeling. In groups where data is sparse, such as guitarfishes, it is unknown which species are at a higher risk of extinction due to illegal trade. Brazil is currently one of the world's largest market for elasmobranch products, but it is uncertain whether the current regulatory measures are effective across all commercial sectors. Here, we applied molecular phylogenetics to identify the species sold as elasmobranchs in Rio de Janeiro. Products labeled as "shark", "ray" and "guitarfish" were sampled from fishmongers, supermarkets, restaurants and street markets (n = 221). Over 60% of the samples were derived from threatened species, reaching 90% in guitarfish and 100% in ray products. The endemic and critically endangered Pseudobatos horkelii was the only authentic guitarfish among all samples labeled as such (n = 75), all others were identified as threatened/endemic rays (Atlantoraja castelnaui , A. cyclophora) or sharks (Squatina guggenheim , S. occulta). S. guggenheim was also detected among the products labeled as "sharks" (n = 113), as were five other endangered shark species: Carcharhinus falciformis , C. signatus , Isurus oxyrhinchus , Sphyrna zygaena and S. lewini. While no mislabeling was observed in supermarkets, the prevalence was high in local trade, indicating that regulatory and awareness-raising measures must be adapted to this economically and socially important sector. [Display omitted] • Among all samples, 36% were mislabeled and 63% derived from endangered species. • Most of the endangered species we detected are endemic to Southwest Atlantic. • No guitarfish samples complied with legislation and 90% were from endangered species. • It is paramount to better regulate the local fresh-fish trade in Rio de Janeiro. [ABSTRACT FROM AUTHOR]

[Display omitted] • 50 % of 260 samples collected across the supply chain for 5 years were mislabelled. • Longitudinal analysis shows regular inspections have reduced the incidence of fraud. • Flatfish nomenclature is inconsistent in the Brazilian labelling legislation. • Mislabelling is driven by monetary gain with an average consumer loss of 40 %. • Flounder mislabelling might contribute to the decline of natural stocks. Over the last few years, molecular species identification has revealed high levels of seafood mislabelling, which has generated public concern. The success of regulatory efforts depends on the accurate estimation of species substitution across multiple points in the supply chain. Flounders are among the most popular and highly valued seafood products marketed in Brazil. However, substitution rates are poorly known in large consumer markets such as Rio de Janeiro. We used sequences of mitochondrial genes to estimate the prevalence of mislabelling in the Brazilian flounder trade. Nearly 50 % (130/260) of fish samples analysed were mislabelled. The prevalence of mislabelling varied across the commercialisation chain and was high in street markets (61 %) and restaurants (82 %), when compared to fishmongers (38 %) and supermarkets (22 %). The most common species used as substitutes were Pangasianodon hypophthalmus (75 %) and Xystreurys rasile (17 %). We show that the 2015 revisions were ineffective in reducing mislabelling and curb inspection by omitting frequently commercialized local pleuronectiforms, such as X. rasile. Substitute species were usually lower-priced, indicating an economic motivation for mislabelling. Our findings reinforce the need for updated and consistent labelling regulations and more stringent control of flounder sales in street markets and restaurants. [ABSTRACT FROM AUTHOR]