Taxonomy, Phylogeny, and Conservation of an Endangered Freshwater Fish Species from Southeastern Brazil: Revisiting Historical Descriptions Using Integrative Approaches

Brycon spp. occur in Neotropical watersheds to the west and east of the Andes, and as they are sensitive to anthropogenic changes, many these species are endangered in southeastern Brazil. Coastal rivers in southeastern Brazil are characterized by the presence of relatively few freshwater fish species and high endemism of this fauna. The objective of this study was to examine whether Brycon spp. occurring in the coastal basins of southeastern Brazil are monophyletic, using cytogenetic data, mitochondrial, and nuclear molecular markers. All the species showed a diploid number of 50 chromosomes, a conserved number within the subfamily Bryconinae. However, the karyotypic formulas were unique to most species, including Brycon devillei (26m+22sm+2st), Brycon ferox (26m+12sm+12st), Brycon insignis (22m+20sm+8st), Brycon opalinus, and Brycon vermelha (24m+20sm+6st), indicating the prevalence of pericentric and paracentric inversions in the chromosomal evolution of these species. All of them had nucleolar organizer regions in the first pair of subtelocentric chromosomes and no equilocal distribution of heterochromatin in the first pair of chromosomes of the karyotype. These two features, not seen in any other Brycon spp. examined to date, indicate that Bryconinae species from the Brazilian southeastern coastal basins, including the monotypic genus Henochilus, are monophyletic. Also, this is the first study that reports NOR location and C-banding patterns as synapomorphies for a Neotropical fish species group. The monophyly was also supported by a phylogenetic analysis of 16S rDNA (16S), cytochrome oxidase subunit I (COI), alpha-myosin (MYH6) genes and S72 intron molecular data. Our results partially corroborate the “Brycon acuminatus” group proposed by Howes in 1982: our proposed clade keeps B. devillei, B. ferox, and B. insignis; but it also includes B. opalinus, B. vermelha, and H. weatlandii whereas it excludes B. nattereri. The phylogeographic unit formed by Bryconinae species in southeastern Brazil reflects the long and isolated paleohydrological history of these coastal basins relative to the continental watersheds.

The sedentary, predatory characin Hoplias malabaricus has one of the widest distributions of freshwater fishes in South America and is characterized by seven karyomorphs (A-G) that occur in sympatric and allopatric populations. Karyotypical patterns of variation in wild populations have been interpreted as evidence of multiple lineages within this nominal species, a possibility that may limit the validity of experimental data for particular karyomorphs. This study used the phylogeographic and genealogical concordance between cytogenetic (N = 49) and molecular (mitochondrial DNA) (N = 73) data on 17 samples, collected in 12 basins from south-eastern and north-eastern Brazil, to assess the systematic value of cytogenetic data. Cytogenetic patterns show a sex chromosome system in the 2n = 40F karyomorph. Molecular and cytogenetic data indicate a long, independent evolutionary history of karyomorphs and a coastal origin of continental populations in south-eastern Brazil. The lack of fit with molecular clock expectations of divergence between groups is likely to be due to strong demographic fluctuations during the evolution of this species complex. The results indicate that karyotypical identification provides a reliable baseline for placing experimental studies on Hoplias spp. in a phylogenetic context.

Allopatric divergence and secondary contact of two weak fish species (Macrodon ancylodon and Macrodon atricauda) from the South Atlantic

On site human observations and video images were collected and compared at the window of the Igarapava Dam fish ladder (IDFL), rio Grande , Southeastern Brazil, between March 1st and June 30th, 2004. We conducted four experiments with two humans (Observer 1 and Observer 2) observing fish passage in the IDFL window while a Sony 3CCD video camera (Observer 3) recorded fish passage at the same time. Experiments, each one hour in length, were distributed throughout the diel cycle using full spectrum lights. We identified fish species, the number of individuals for each species, and the real time that they passed. Counts from each human observer were compared to the video counts. The fish species most commonly observed in the window were - curimba (Prochilodus lineatus), mandi-amarelo (Pimelodus maculatus), piau-três-pintas (Leporinus friderici) and ferreirinha (Leporinus octofasciatus). The number of species and individuals were indistinguishable for the three observers. But, the number of species and individuals were significantly different among experiments. Thus, the three observers register the same number of species and count the same number of individuals even when these two response variables differ significantly among experiments. Based on these results, we concluded that the video count was an accurate method to assess fish passage at the IDFL.

Length–weight relationships (LWRs) were determined for four fish species from two drainage areas, those of the Itapemirim and Jucu River, in the state of Espirito Santo, southeastern Brazil. Fishes were collected between May 2015 and November 2016, with gill nets, casting net, dip net, and sieve. Herein are presented LWRs for Astyanax lacustris, Astyanax taeniatus, Hyphessobrycon bifasciatus and Oligosarcus acutirostris.

This study aimed to estimate the parameters of length-weight relationship, sex ratio, and diet of three freshwater fish species that inhabit streams in the Pomba River basin (Rio de Janeiro, Brazil). Fishes were sampled with seine nets (2.0 × 1.20 m, 2 mm mesh size) and dip nets (0.46 × 0.33 m, 2 mm mesh size) from October to December 2018. Measurements were taken for total length (TL - 0.1 cm precision) and total weight (TW - 0.01 g precision). Growth model parameters were estimated. This study provides new length-weight relationship data for Deuterodon intermedius (Eigenmann, 1908), Australoheros paraibae Ottoni & Costa, 2008, and Hypostomus punctatus Valenciennes, 1840. All of them ingested a wide variety of food items, including plant material like algae, animal material such as terrestrial and aquatic insects, and undefined matter such as detritus or mud. The three species showed a higher number of females. Our study provides basic information for functional diversity studies, as well as for future investigations associated with the evaluation of anthropic impacts, either occasional or chronic, on the fish assemblage structure of the Pomba River basin.

The physical habitat simulation sub-routine of the Instream Flow Incremental Methodology (IFIM) uses hydraulic modeling and suitability indices of target fish species to predict how differences in-stream flows affect the microhabitat occupation by fish species. This habitat modelling approach was adopted to assess the ecological effects of running flows on three neotropical fish species of different orders (Bryconamericus ornaticeps , Ancistrus multispinis and Geophagus brasiliensis ).The study encompassed two reaches of an Atlantic Forest stream in Southeastern Brazil where topographic and hydraulic (depth, velocity and type of substrate) characteristics were measured to implement one-dimensional hydraulic simulation. Sub aquatic observation of fish was performed to collect data on microhabitat use and these data were used to develop habitat suitability curves that were used in the habitat simulation to obtain the habitat suitability index (HSI) and weighted usable area (WUA) versus flow curves. Upon these curves minimum and optimum environmental flows for the target fish species were proposed. Bryconamericus ornaticeps and A. multispinis selected microhabitats around 0.6 m depth, whereas G. brasiliensis showed a wider suitable range (0.35-0.9 m). All the three species were mainly observed in microhabitat with low flow velocity (0.1 m/s). Bryconamericus ornaticeps selected more frequently coarse substrate (e.g. boulders) but it appeared also over sandy substrate, whereas A. multispinis and G. brasiliensis selected preferably boulders. The range of 0.65-0.85 m3/s was found as the optimum to meet the needs of the three fish species. Our results agree with the necessary objective information to perform grounded management actions in the frame of a management program aiming at ecosystem conservation. Thereby it can be considered a successful pilot study in environmental flow assessment in an Atlantic Forest stream of Brazil.

16 th February 2015. Due to a number of missing tables and figures, this article (DOI: http://dx.doi.org/10.3329/jesnr.v7i1.22144 ) was withdrawn from Vol.7(1) and has been republished with corrections in Vol.7(2) pp.177-184 (DOI: http://dx.doi.org/10.3329/jesnr.v7i2.22228 ). An investigation was carried out on the fish marketing system and availability of fish species at Daulatpur fish market in Khulna over 12-months from September 2012 to August 2013. Combinations of the participatory, qualitative and quantitative methods were used for questionnaire interviews for data collection. A total of 115 species of fresh water, brackish and marine water fish and crustacean species were identified during the observation period. The number of fresh water fish species was found 60 including 14 fresh water culture species and 12 SIS whereas brackish and marine water species was found 41 and crustacean species was 14 including 5 fresh water prawn, 6 marine and brackish water shrimp and 3 crabs. During the observation period, it was found that the availability of culture fish species was higher in the market and it was 55.86% including 17% catfish, 15.65 % tilapia, 15.56 % carp fishes, 4.18% koi, 2.47% punti and 1% prawn. Catfish, carps, tilapia, snakehead, baim, shing-magur, punti, koi etc were the major abundant groups among the fresh water fish species whereas ilish and some shrimp were the abundant species of marine and brackish water fish. The highest abundance (55.86%) was found the fresh water culture fish species following to marine and brackish water species (28.01%) and fresh water capture species (16.01%). The market chain from farmers/fishermen to consumers encompassed mainly primary, secondary and retail markets involving local agents (foria and bepari) suppliers, aratdars, wholesalers and retailers. During the observation, it was found that the auctioneers get 3 to 5% commission by performing their activities. Aratdars also get 4 to 5% commission due to arrange auctioning activities and providing other facilities such as clean water supply, electricity, space, communication etc which is called aratdary. In some cases farmers have to pay market tools that locally called khazna which vary from 5 to 10% depending on amount of sales. Market structure, species quality, size and weight have an influence on the price of fish and it was found that the price of fish increases per kilogram with increasing size and it varied with species to species. Every step of intermediaries of marketing channel obtained certain amount of profit and ultimately the farmers/fishermen received an average near about 60 percent of the retail price of fish in the market. DOI: http://dx.doi.org/10.3329/jesnr.v7i2.22228 J. Environ. Sci. & Natural Resources, 7(2): 177-184 2014

Summary Here the length–weight relationships (LWR, hereafter) of Pareiorhina pelicicei, Trichomycterus candidus, T. pirabitira, and T. piratymbara are provided. Samples of each species were collected between April and July 2017 with a hand net (1.5 mm mesh) in three sites from the upper Parana River basin, Southeastern Brazil. These results increase knowledge about the LWR of Neotropical freshwater fish.

Perfluoroalkyl substances associations with morphometric health indices in three fish species from differentially contaminated water bodies in Southeastern Brazil

We analyzed the stomach contents of 116 individuals belonging to seven fishes species in order to investigate seasonal changes in feeding strategy and how trophic interactions between species affect community structure in an Atlantic rainforest stream in Southeastern Brazil. Oligosarcus hepsetus and Pimelodus sp. consumed fewer items during the winter. Phalloceros caudimaculatus switched feeding habits from detritus during summer to algae during winter. These examples are related to variations in food availability and species feeding selectivity. The highest diet overlap values, for most species, as measured using Schoener's index, were observed in summer, along with a species tendency to be more generalist. Feeding pattern variation may influence the fish community structure.

Compiled inventories with information on the distribution, status and impacts of invasive alien species are essential for the study, management and monitoring of biological invasions. Despite their great importance, such studies are lacking for alien freshwater fish species in Brazil. Therefore, our aim was to improve the knowledge of the regional richness of alien species, leading to the closing of existing regional data gaps. We performed extensive bibliographic research and consulted with experts to update the list of freshwater alien fishes of six watersheds in southeastern Brazil (Upper Parana, Paraiba do Sul, Sao Francisco, Mucuri, Jequitinhonha and Doce), and provided information on species invasion status, environmental impact category, pathway of introduction, origin and species taxonomic attributes. We compiled a list of 201 alien fish species introduced in the six watersheds (to 2019) through six pathways: aquarium trade, geographical barrier breach (after the flooding of a natural barrier by the construction of a hydroelectric power plant), aquaculture, stocking for sport fishing, live bait and biological control. The invasion status of the species varied among watersheds, and it was possible to characterize the impact of only 11 species. Our results show there are detailed data on the distribution and population status of alien fishes in Brazil, but also a lack of ecological studies on the impacts of such introductions. Research on the impacts of alien fish species on recipient ecosystems are urgently needed owing to the present high number and wide distribution of invasive species and lack of knowledge on the consequences of these invasions.

Endangered whale sharks in southeastern Brazil: Records and management issues

This study presents new information on feeding habits of Guiana dolphins, Sotalia guianensis, in south-eastern Brazil, together with new regression equations to evaluate the weight and length of fish from otoliths, showing an overview on the knowledge about this species’ diet in this area. Eighteen stomach contents had been analysed and compared to 180 samples collected in another eight feeding studies. The analysed specimens were either incidentally caught in gillnets used in coastal waters by the fleet based in the Cananéia main harbour (25°00′S 47°55′W), south of São Paulo State, or found dead in inner waters of the Cananéia estuary between 2003 and 2009. Based on the index of relative importance analysis, the most important fish species were the banded croaker, Paralonchurus brasiliensis. Doryteuthis plei was the most representative cephalopod species. Stellifer rastrifer was the most important fish species observed in dolphins in inner estuarine waters and P. brasiliensis in recovered dolphins from coastal waters. Loliguncula brevis is the only cephalopod species reported from dolphins found in inner estuarine waters up to date. Doryteuthis plei was the most important cephalopod species observed in coastal dolphins. When considering other feeding studies, the most representative fish family in the diet of S. guianensis was Sciaenidae, which is mainly represented by demersal fishes. The main preys of S. guianensis are abundant in the studied areas, which may indicate an opportunistic feeding habit. The majority of them are not the most important target species by the commercial fishery in south-eastern Brazil.

During a study of the Monogenea from some Australian native freshwater fishes found in south-east Queensland, a review of the literature was made to enumerate Australia's freshwater monogenean fauna. Twenty-six named species of Monogenea have been described from 16 species of native freshwater fishes. A further 16 records of monogeneans have been reported from native and introduced freshwater fishes, but these parasites await specific description. The only published record of a monogenean from an introduced species of freshwater fish in Australia is Gyrodactylus kobayashii Hukuda, 1940 from the goldfish Carassius auratus. An attempt is made to predict the biodiversity of the monogenean fauna of Australia's 180 species of freshwater fishes by applying a conservative estimate of three species of Monogenea per species of freshwater fish from a survey of relatively common freshwater fish species in subtropical south-east Queensland. This indicates that only 5% of an estimated 500 species of Monogenea have been described so far. An historical review of the study of the Monogenea from freshwater fishes in Australia and an updated parasite-host checklist is presented.