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The influence of population structure and reproductive aspects of the genus Stellifer (Oken, 1817) on the abundance of species on the southern Brazilian coast
Rodrigues-Filho, JL.;Verani, JR.;Peret, AC.;Sabinson, LM.;Branco, JO.;
Brazilian Journal of Biology , 2011, DOI: 10.1590/S1519-69842011000500019
Abstract: the differences between abundance and the relationship with aspects of population and reproductive stellifer rastrifer, stellifer stellifer and stellifer brasiliensis were analysed. data were collected monthly trawl directed for capture of seabob shrimp in arma??o do itapocoroy, an important fishing area on the southern brazilian coast. the chi-square test showed that the population of s. rastrifer presented values of capture significantly higher than others in all evaluated periods. the frequency distribution of total length curves combined with records of the size at first maturity (l50) showed that s. rastrifer is a species with a majority of the adults effectively participating in the reproductive period. the frequency of occurrence of individuals in reproduction monthly examined together with changes in the gonadosomatic index (gsi) and the reproductive activity index indicated that spring was the main breeding season for the three species. however, it was observed that the reproductive period of s. rastrifer was more pronounced and more extensive than that of its congeners, apparently providing it with ecological advantages and enabling a more effective population balance given the pressure exerted by fishing in the study area.
Seasonality, Dietary Overlap and the Role of Taxonomic Resolution in the Study of the Diet of Three Congeneric Fishes from a Tropical Bay  [PDF]
Maíra Pombo, Márcia Regina Denadai, Alexander Turra
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0056107
Abstract: Not only seasonality but also taxonomic resolution of prey categories has been shown to affect diet studies. We analyzed the stomach contents of three sympatric species, Stellifer rastrifer, S. brasiliensis and S. stellifer, sampled monthly from August 2003 to October 2004 in Caraguatatuba Bay, southeastern Brazil. General characteristics and similarities among their diets were evaluated by considering high taxonomic ranks of all prey groups, and also the lower taxonomic ranks of the main prey groups. Dietary similarity was relatively high among species and low between seasons, and both evaluation criteria gave the equivalent results. The rare items, however, provided information about resource partition, and the species compositions of the most important groups were apparently good indicators of food availability.
Molecular Phylogeny of Weakfish Species of the Stellifer Group (Sciaenidae, Perciformes) of the Western South Atlantic Based on Mitochondrial and Nuclear Data  [PDF]
Andressa Jisely Barreto Barbosa, Iracilda Sampaio, Horacio Schneider, Simoni Santos
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0102250
Abstract: The phylogenetic relationships within the Stellifer group of weakfishes (Stellifer, Odontoscion, Ophioscion, and Bairdiella) were evaluated using 2723 base pairs comprising sequences of nuclear (rhodopsin, TMO-4C4, RAG-1) and mitochondrial (16S rRNA and COI) markers obtained from specimens of nine species. Our results indicate a close relationship between Bairdiella and Odontoscion, and also that the genus Stellifer is not monophyletic, but rather that it consists of two distinct lineages, one clade containing S. microps/S. naso/S. brasiliensis and the other, S. rastrifer/S. stellifer/Stellifer sp. B, which is closer to Ophioscion than the former clade. The O. punctatissimus populations from the northern and southern Brazilian coast were also highly divergent in both nuclear (0.8% for rhodopsin and 0.9% for RAG-1) and mitochondrial sequences (2.2% for 16S rRNA and 7.3% for COI), which we conclude is consistent with the presence of two distinct species. The morphological similarities of the members of the Stellifer group is reinforced by the molecular data from both the present study and previous analyses, which have questioned the taxonomic status of the Stellifer group. If, on the one hand, the group is in fact composed of four genera (Stellifer, Ophioscion, Odontoscion, and Bairdiella), one of the two Stellifer clades should be reclassified as a new genus. However, if the close relationship and the reduced genetic divergence found within the group is confirmed in a more extensive study, including representatives of additional taxa, this, together with the morphological evidence, would support downgrading the whole group to a single genus. Obviously, these contradictory findings reinforce the need for a more systematic taxonomic revision of the Stellifer group as a whole.
Reproductive biology and spatio-temporal distribution of Stellifer rastrifer, Stellifer naso and Macrodon ancylodon (Sciaenidae) in the Caeté estuary, northern Brazil
Camargo, Mauricio;Isaac, Victoria;
Brazilian Journal of Oceanography , 2005, DOI: 10.1590/S1679-87592005000100002
Abstract: this study analyses the spatial and temporal distribution of the dominant sciaenids in the caeté estuary on the northern coast of brazil. samples were taken by otter trawls in four areas of the caeté estuary between october 1996 and august 1997 six bimonthly. stellifer rastrifer, stellifer naso and macrododon ancylodon presented the highest biomass out of eleven species of sciaenidae caught. minimum and mean length at first maturity were calculated and the main spawning periods determined. changes in the spatio-temporal distribution of the three species were related to seasonal changes in estuarine salinity and spawning pulses. larvae and juveniles of s. rastrifer, s. naso and m. ancylodon were found in the inner estuary while larger specimens were more abundant in the outer estuary with higher salinities. m. ancylodon spawned from october to february and rested from april to august whereas s. rastrifer and s. naso spawned throughout the year, though with two peaks, in october-december and june.
Aspectos bioecológicos de Stellifer rastrifer (Perciformes: Sciaenidae) na Baía de Santos, SP
Giannini, Roberto;Paiva Filho, Alfredo Martins;
Boletim do Instituto Oceanográfico , 1990, DOI: 10.1590/S0373-55241990000100007
Abstract: as many as 7,260 specimens of the sciaenid stellifer rastriferwqtg collected through a monthly beach seine and bottom trawl survey in the complex bay-estuary of santos and s?o vicente, between march 1985 and may 1986. the occurrence, abundance, length frequency, influence of environmental factors, length-weight relationship, growth, recruitment and mortality were analysed..?, rastrifer occurred year-round and was more abundant and frequent in fall at west side of medium and inner stracta. young of the year was first caught from january to may in deeper water areas and later they were found in shallow areas low with salinity and high temperature. the low catches found in spring may be related to a massive emigration to open sea (summer spawning). s. rastrifer showed higher values for growth coefficient and for total mortality and exploitation rates.
Aspectos bioecológicos de Stellifer rastrifer (Perciformes: Sciaenidae) na Baía de Santos, SP
Giannini, Roberto;Paiva Filho, Alfredo Martins;
Brazilian Journal of Oceanography , 1990, DOI: 10.1590/S1679-87591990000100007
Abstract: as many as 7,260 specimens of the sciaenid stellifer rastriferwqtg collected through a monthly beach seine and bottom trawl survey in the complex bay-estuary of santos and s?o vicente, between march 1985 and may 1986. the occurrence, abundance, length frequency, influence of environmental factors, length-weight relationship, growth, recruitment and mortality were analysed..?, rastrifer occurred year-round and was more abundant and frequent in fall at west side of medium and inner stracta. young of the year was first caught from january to may in deeper water areas and later they were found in shallow areas low with salinity and high temperature. the low catches found in spring may be related to a massive emigration to open sea (summer spawning). s. rastrifer showed higher values for growth coefficient and for total mortality and exploitation rates.
Feeding habits of Stellifer rastrifer (Perciformes, Sciaenidae) at Guaratuba mangrove, Parana, Brazil
Chaves, Paulo de Tarso C.;Vendel, Ana Lúcia;
Brazilian Archives of Biology and Technology , 1998, DOI: 10.1590/S1516-89131998000400006
Abstract: feeding habits of stellifer rastrifer (perciformes, sciaenidae) at guaratuba mangrove, parana, brazil, were studied from february 1996 to february 1997. it was observed that its diet was based on invertebrates, mainly decapoda non-brachyura and polychaeta. in a smaller proportion there were plants, copepoda, gammaridea and mollusca. the level of contribution of each food item changed according to the season and the individual size. such plasticity in feeding behaviour was similar to that described to some fish populations from other estuaries, and could be an indicator of the high level of instability presented by this kind of ecosystem.
Cultura experimental de seringueira (Hevea Brasiliensis Muell.-Arg.) no município de Caraguatatuba
Cunha, Jo?o Ferreira da;
Bragantia , 1963, DOI: 10.1590/S0006-87051963000100003
Abstract: a rubber tree (hevea brasiliensis muell. arg.) experimental plot was established in the caraguatatuba area (coastal area in the state of s?o paulo) to study its adaptation to this new habitat, as well as to determine the rubber yield in the early tappings. this pilot planting, the first in the area, has shown excellent growth and given better than average rubber yields. the product obtained was submitted to technological test and proved to be of superior quality. the results obtained in this experimental planting indicate that the rubber plant can be grown and explored successfully in that region.
Food categories reconstruction and feeding consumption estimates for the Sciaenid Macrodon ancylodon (Bloch & Schneider), and the congeneric fishes Stellifer rastrifer (Jordan) and Stellifer naso (Jordan) (Pisces, Perciformes) in the Caeté Estuary, Northern Coast of Brazil
Camargo, Mauricio;Isaac, Victoria;
Revista Brasileira de Zoologia , 2004, DOI: 10.1590/S0101-81752004000100015
Abstract: a quantitative method to estimate fish feeding consumption and energy intake from different food categories through the reconstruction of ingested preys based on hard not digestible body structures is presented. in order to establish the equations of the functional relationships between preys weight and body structures, stomachs of 1.086 specimens of macrodon ancylodon (bloch & schneider, 1801), stellifer rastrifer (jordan, 1889), and stellifer naso (jordan, 1889) fish species were dissected. consequently, preys reconstruction enabled a quantitative evaluation of food categories consumption. results indicate a marked difference in diet composition and energy requirements according to fish species ontogenetic development.
Reprodu??o de Stellifer rastrifer (Jordan) (Teleostei, Sciaenidae) na Baía de Guaratuba, Paraná, Brasil
Chaves, Paulo de Tarso da Cunha;Vendel, Ana Lúcia;
Revista Brasileira de Zoologia , 1997, DOI: 10.1590/S0101-81751997000100008
Abstract: a total of 1312 individuais of s. rastrifer were sampled from march 1994 to september 1996 at the guaratuba bay, southern brazilian coast. this species is a permanently inhabitant of the mangrove area throughout the year. the weight/length relationship of the species in the region is "in tw =-12,35 + 3,22 in tl", and the individuais may reach 172mm of total length. the analyses of gonadal morphology and gonadossomatic index indicate that s. rastrifer is a multiple spawner species, that reproduces at the mangrove area during a long period of the year. the reproductive activity is more intense during the winter and mainly the spring, when the value of condition factor declines and empty folheies are found in the ovaries.
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