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Stomach contents of 175 Brazilian sharpnose sharks, Rhizoprionodon lalandii, were examined to assess their feeding habits. Caught by artisanal fishers between June 2006 and July of 2007 at Ipanema Beach, on the central coast of the state of Paraná, southern Brazil, R. lalandii appears to be piscivorous (89.7% IRI), feeding mainly on families of Clupeidae (5.1% IRI) and Sciaenidae (3.7% IRI) and secondarily on squid Lolliguncula brevis (8.6% IRI). Diets were similar between sexes and seasons. However, there were ontogenetic changes in their diets. The major items for neonates were Penaeidae crustaceans (%IRI = 56.4) and Engraulidae fishes (%IRI = 29.3); for the juveniles, Sciaenidae (%IRI = 62.5) and Clupeidae (%IRI = 19.7), and for adults Clupeidae (%IRI = 45.8) and Sciaenidae (%IRI = 15.9). Only neonate sharks consumed crustaceans, whereas all size classes consumed cephalopods and teleosts. Neonates had the lowest trophic level (TR = 3.8), with the diet of juveniles and adults the highest (TR = 4.2). Given its abundance and diet, R. lalandii may be an important predator of demersal and pelagic prey in coastal waters of Brazil. [ABSTRACT FROM AUTHOR]

The article presents a research study regarding the non-standard fishing of large sharks in Paraná, Brazil. Research shows the shark species that are being fished in the state including Elasmobranch, Trichiuridae, Rhinopteridae, and rays and 60 specimens have already recorded. Furthermore, dusky sharks are commonly caught by Brazilian fishermen in the coastal area of the state.

The article focuses on the occurrence of the alien invasive loach Misgurnus anguillicaudatus in the River basin in southern Brazil. Seven juveniles and one adult M. anguillicaudatus ranging from 63 to 131 mm standard length (SL) were collected between 2000 and 2008 in the shallowest parts of small forested streams, flooded areas, and channel margins of the upper and middle River basin.

The combination of highly equipped smartphones, with the increased use of social media, has offered a wide database. Given this, citizen science can be used to record and monitor non‐native fish fauna, target new samples and collaborate with monitoring occurrences in new areas. We aimed to demonstrate the efficiency of social media in citizen science as a tool to cooperate with monitoring studies of non‐native species. Consequently, we determined the occurrence points of S. brasiliensis in the Iguaçu River basin, indicating sites of greatest occurrence and analyzing the impact of the invasion on the native fauna of the basin. Files and information available on the YouTube® and Facebook® media platforms were used as data, was carried out from April 2019 to April 2020. The results were 40 records, 22 videos obtained from Youtube, and seven videos and 11 photos from Facebook, the oldest record was from April 2013, while the largest number of posts was in 2016. Fish records available from online platforms can reveal the occurrence and progressive dispersion of species, in the context of biological invasions, these tools can be of great value in studies that aim to follow the progress of introduced species, contributing by helping to direct new sampling programs and corroborating the occurrence of species in new areas in conjunction with standard monitoring programs. Based on citizen science records, it was possible to update the range of occurrence of the non‐native S. brasiliensis in the Iguaçu River basin, cooperating with scientific knowledge. Innovative monitoring and control measures are necessary to deal with invasive species, with citizen science proving to be competent for determining the occurrence of species and showing promise in the entire field of ichthyology. [ABSTRACT FROM AUTHOR]

Sharks and rays caught by a small-scale fisheries in the western equatorial Atlantic Keywords: artisanal fisheries; Chondrichthyes; conservation; elasmobranch; endangered species EN artisanal fisheries Chondrichthyes conservation elasmobranch endangered species 830 833 4 12/21/20 20201201 NES 201201 INTRODUCTION The more than 1,100 known species of sharks and rays (Weigmann, 2016) are important trophic components of marine ecosystems. DISCUSSION This is the first study to use systematic monitoring of fisheries landings to describe the coastal fauna of elasmobranchs for the Ceará state and one of few for northeastern Brazil. The most captured and landed elasmobranch species at the Mucuripe embayment, I H. americanus i and I R. porosus i , are currently considered Data Deficient in Brazil (ICMBio, 2016). [Extracted from the article]

Isopisthus parvipinnis, commonly known as "bigtooth corvina", is a marine estuarine‐dependent fish captured in the southeast and south Brazilian coast as bycatch of the shrimp fishery. This work used the sagittae morphology as a tool to primarily study the population structure of I. parvipinnis between São Paulo and Santa Catarina states (23ºS to 26.9ºS) in Brazil. Secondly, it intended to verify the existence of morphological alterations over time, by comparing otoliths of fish captured in 1975 and 2018/2019. Otolith shape analyses were performed in individuals ranging from 66 to 139 mm of total length, obtained from historical (1975) and present catches (2018/2019) in the shallow coastal areas off North of São Paulo (NSP), Centre of São Paulo (CSP), South of São Paulo (SSP), Paraná (PR) and Santa Catarina (SC). Otoliths were analyzed using shape indices (SIs), elliptical Fourier descriptors (EFDs) and both tools combined. Morphological variations among locations and between years were tested using uni and multivariate statistics. Data showed regional differences in the otolith shape analysis over the years. Samples from 1975 presented an overall low reclassification rate (43%), with a high overlap of individuals among locations, suggesting the existence of a single group. Differently, samples from 2018/2019 discriminated four distinct spatial units with a good overall reclassification (74%): group 1 ‐ NSP; group 2 ‐ CSP; group 3 ‐ SSP + PR; and group 4 ‐ SC. The hereby data suggests regional changes at long term in the population dynamics of I. parvipinnis, from a single panmictic population in the past to a metapopulation structure in the present days, with consequences for the rational and sustainable management of the fishery. However, once it was the first evaluation of the population structure of I. parvipinnis, it is highly recommended to use complimentary phenotypic and/or genetic approaches to corroborate the hereby observed findings. [ABSTRACT FROM AUTHOR]

Largemouth Bass (Micropterus salmoides) have been introduced on a global scale for sport fishing but represent a conservation concern given their documented negative impacts on native faunal diversity and abundance. Recent research using molecular data to characterize invasive Largemouth Bass populations elsewhere has demonstrated that populations are typically characterized by limited genetic diversity, or represent a combination of Largemouth Bass and Florida Bass (Micropterus floridanus). To test whether these traits were consistent with invasive populations in Brazil, we generated mitochondrial sequence data from four established populations of Largemouth Bass collected in southern Brazil as well as a local aquaculture facility to confirm species identity and quantify levels of genetic diversity. We identified the exclusive presence of Largemouth Bass in the region and observed limited levels of haplotype (haplotype diversity = 0.0684, SE = 0.038) and nucleotide diversity (0.0003, SE = 0.0002) which suggested the presence of a founder effect associated with introduction. Each of the four populations were dominated by a single haplotype that was identical to one recovered from a nearby aquaculture facility, which identified this facility as a potential introduction source. [ABSTRACT FROM AUTHOR]

Sagitta otoliths are usually formed of calcium carbonate polymorphs as aragonite. The objective of this study was to verify which carbonate polymorph is predominant in the sagitta otolith of Menticirrhus americanus and check whether this pattern remains in otoliths with morphological alterations. Otoliths of M. americanus were obtained from five sites on the southeast‐south coast of Brazil (São Sebastião (SS) 23°45′S–45°24′O, n = 29; Cananéia‐Iguape Estuarine Complex (CI) 25°02′S–47°54′O, n = 30; Paranaguá Estuarine Complex (PEC) 25°28′S–48°20′O, n = 35; Itapoá (IT) 26°07′S–48°36′O, n = 31; Laguna (LA) 28°28′S–48°46′O, n = 13). The characterization of carbonate polymorphs of otoliths was performed through Raman spectroscopy, a photonic and non‐destructive technique that analyzes molecular vibrations induced by laser. We analyzed 138 pairs of M. americanus otoliths, of which eight otoliths from different pairs presented morphological alterations (SS n = 1, CEP n = 5, IT n = 1, LA n = 1). The Raman spectra show that normal otoliths, that is, without morphological alterations, presented only aragonite in their structure. Among the otoliths that presented morphological alterations, the Raman spectra allowed to identify in six otoliths the deposition of aragonite and in only two otoliths the deposition of vaterite (one specimen of the PEC and one of SS). [ABSTRACT FROM AUTHOR]

We reported the genus Parasphyraenops (Perciformes: Serranidae) in the Brazilian Biogeographic Province. Four Parasphyraenops incisus specimens were identified based in body shape and color pattern through underwater remote video records, on shallow coral reefs in the Bahia state, Brazil. In the video frames P. incisus was observed swimming close to the pomacentrid Chromis multilineata at 14 m depth, being this the shallowest record for this species. The present record expands on 6.500 km the southern limit of distribution of P. incisus in the Western Atlantic. [ABSTRACT FROM AUTHOR]

Summary: This contribution presents a brief morphometric description of adult females and embryos of the ray Gymnura altavela. Two females, pregnant with a total of five embryos, were captured in Rio de Janeiro, southeastern Brazil, and their morphometry was compared to their respective embryos. The embryos showed higher body proportions (%DW) than adults, regardless of sex, which may be an effect of ontogeny. [ABSTRACT FROM AUTHOR]

Knowing the trophic level of marine organisms is essential to understanding their ecological role in the ecosystem and for quantifying the ecosystem effects of fishing to establish effective management of fishing resources. In comparison to other systems, information about the trophic level of marine organisms in the Persian Gulf and Oman Sea is very scarce. Here, the main aim was to estimate trophic level in these areas using all available diet information from different marine species using TrophLab software. The trophic level of 32 fish species was estimated with the available diet data. The trophic level ranged from 2.28 to 4.50. High trophic levels were found for Chorocentrus nudus ( TL = 4.7), Saurida tumbil ( TL = 4.6), Rhizoprionodon acutus ( TL = 4.5), Torpedo sinuspersici ( TL=4.5), Gymnura poecilura ( TL = 4.5), Sphyraena putnamae ( TL = 4.5) and Euthynnus affinis ( TL = 4.5). In contrast, lower trophic levels were estimated for Tenualosa ilisha ( TL = 2.28) and Sardinella sindensis ( TL = 2.92). As expected, a positive correlation was found between the trophic level and body size, indicating changes in the diet due to variations in predatory capacities. The results of this study may be useful in the formulation of trophic indicators and modelling of the ecosystems. [ABSTRACT FROM AUTHOR]

The diets of the milk shark, Rhizoprionodon acutus, and the slit-eye shark, Loxodon macrorhinus, landed from the artisanal fishery in the Arabian Gulf waters of the United Arab Emirates were investigated to determine their dietary preferences. Stomach contents from 57 milk sharks and 53 slit eye sharks were collected from Abu Dhabi ( R. acutus, n = 23), Dubai ( R. acutus, n = 5; L. macrorhinus, n = 15) and Ras Al Khaimah ( R. acutus, n = 29; L. macrorhinus, n = 38) during fishery surveys from January to May 2012. Prey items were identified to the lowest possible taxonomic level, grouped into five categories including 'teleost fish', 'cephalopods', 'crustaceans', 'invertebrates', and 'other'. The diets of both species were described using the numeric, frequency and weight methods, and the index of relative importance ( IRI). The majority of stomachs for both species had food, with 66.6% of milk shark stomachs and 90.5% of slit-eye shark stomachs containing prey items, both dominated by small teleosts. Rhizoprionodon acutus fed on a wide variety of teleost species, primarily Engraulidae (anchovies) (28%), Gerreidae (mojarras) (5.6%) and Carangidae (jacks) (1.6%) with occasional crustacean and cephalopod prey (8%). On the other hand, L. macrorhinus seemed to have a preference for one species in terms of teleosts (anchovies) (35.1%) and fed on a wider variety of crustaceans and cephalopods (22.6%). There was little overlap in the diets of these two species, suggesting that they may either be using different habitats or that in these waters, the milk shark is a generalist species while the slit-eye is a specialist feeder. [ABSTRACT FROM AUTHOR]

The article discusses the study on the occurrence of dojo fish (Misgurnus anguillicaudatus) in the Upper Paraná River Basin in southeastern Brazil. The study shows the impact of a variety of environments on the species wherein morphometric differences have found on the captured species. The study suggests that the species could easily establish itself when released in a non-native environment.

The article presents a study of the effectiveness of the ban on the importation of 10 non-native fish species by aquarium stores in Brazil, with consideration on management options. The Federal Normative Instructions No. 202 and No. 203 of 2008 for saltwater and freshwater fish species passed by the Brazilian Institute of Environment and Renewable Natural Resources (IBAMA). It says that the frequency of the non-native species in the aquarium trade endangers aquatic life in Brazil.

This study reports the length-weight relationships ( LWRs) for two elasmobranch species, Rhinobatos horkelii Müller & Henle, 1841 and Zapteryx brevirostris (Müller & Henle, 1841) collected from the southwestern Atlantic, off Brazil. Both are considered endangered species. The LWR data can be taken into consideration for further management and conservation plans. [ABSTRACT FROM AUTHOR]