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4.
Mar Pollut Bull ; 114(1): 123-133, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27641110

RESUMO

The Abrolhos Bank is an area of high ecological, socio-economic importance and harbour the richest and most-extensive coral reefs in the South Atlantic. Here we report the discovery of shallow (12-25m depth) reef complex with ten large biogenic structures, intermediate between the typical mushroom-shaped pinnacles of the northern Abrolhos Bank (17°-18° S) and the small patch reefs found on the central/southern coast of the Espírito Santo State (19°-20° S). The newly discovered reefs harbour a relatively rich and abundant reef community, with 73 fish and 14 benthic cnidarian species, including endangered and commercially important ones. We discuss on urgent needs of properly mapping and understanding the ecological functioning of this reef system. Information provided here is a baseline for future impact evaluations, particularly considering the recent worst environmental disaster of Brazil from a dam collapse in Doce river that affected the region.


Assuntos
Conservação dos Recursos Naturais , Recifes de Corais , Animais , Antozoários/crescimento & desenvolvimento , Brasil , Ecologia , Meio Ambiente , Peixes , Poluição da Água/prevenção & controle , Poluição da Água/estatística & dados numéricos
5.
Braz. j. biol ; 76(3): 743-749, tab, graf
Artigo em Inglês | LILACS | ID: lil-785025

RESUMO

Abstract Many aspects of sex change in reef fishes have been studied, including behavior and social organization. However, gonad histology remains the most robust way to identify sexual patterns in fishes. Some uncommon tissues remain poorly described, such as the accessory gonadal structures found in species from the Gobiidae family, which are rare in other bony fishes. This is the first report of the testicular gland in Gramma brasiliensis and for the Grammatidae family. Between April 2011 and February 2012 eighty specimens were collected during four dive campaigns on the Taipus de Fora reef (13°56’20”S 38°55’32”W), Bahia, Northeast Brazil, and their sex was determined. Thirteen per cent of the active-females and 90% of the active-males had testicular gland tissue in their ovotestis. This discovery led to additional research into the characteristics of the gland tissue and its relationship with gonadal maturation. Three patterns of testicular gland development were found in Brazilian basslet ovotestis. Both ova and sperm-producing gonad contained testicular gland tissue, and the appearance of this tissue seems to be the first modification of ovotestis tissue marking the beginning of the protogynous sex-change process in G. brasiliensis.


Resumo Diversos aspectos da troca de sexo em peixes recifais vem sendo estudados, incluindo comportamentos e organização social. Entretanto, a histologia das gônadas continua sendo a maneira mais robusta para se identificar padrões sexuais em peixes. Alguns tecidos incomuns, tais como as estruturas anexas a gônada encontradas em espécies da família Gobiidae e raras em outras espécies são pouco estudados. Este trabalho é a primeira descrição da glândula testicular em Gramma brasiliensis e para a família Grammatidae. Entre abril de 2011 e fevereiro de 2012, oitenta espécimes foram coletados durante quatro amostragens no recife de Taipus de Fora (13°56’20”S 38°55’32”W), Bahia, Brasil, e tiveram seus sexos determinados. Treze por cento das fêmeas ativas e noventa por cento dos machos ativos apresentaram tecido da glândula testicular em suas gônadas. Esta descoberta levou ao estudo da características dessa estrutura e sua relação com a maturação gonadal. Foram identificados três padrões de desenvolvimento da glândula testicular nas gônadas do Gramma brasiliensis. Tanto as gônadas produtoras de espermatozoides quanto as de oócitos apresentaram tecido da glândula testicular, e o surgimento desse tecido parece ser a primeira modificação gonadal do início da troca de sexo protogínica em G. brasiliensis.


Assuntos
Animais , Masculino , Feminino , Testículo/fisiologia , Perciformes/fisiologia , Adaptação Fisiológica/fisiologia , Organismos Hermafroditas/fisiologia , Brasil , Gônadas/fisiologia
6.
J Fish Biol ; 89(1): 876-89, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27264779

RESUMO

In this study, seasonal numerical abundance of the critically endangered Atlantic goliath grouper Epinephelus itajara was estimated by conducting scuba dive surveys and calculating sightings-per-unit-effort (SPUE) at three sites in southern Brazil. Seasonal differences in size and reproductive condition of captured or confiscated specimens were compared. The SPUE differed significantly with season, increasing in late spring and peaking during the austral summer months. A significant effect was observed in the number of fish relative to the lunar cycle. All females sampled during the summer were spawning capable, while all those sampled during other seasons were either regressing or regenerating. What these data strongly infer is that the E. itajara spawning aggregation sites have been located in the southern state of Paraná and the northern state of Santa Catarina and summer is the most likely spawning season. Size frequency distributions, abundance and reproductive state were estimated and correlated with environmental variables.


Assuntos
Bass/fisiologia , Reprodução , Comportamento Social , Animais , Bass/anatomia & histologia , Brasil , Feminino , Masculino , Lua , Ovário/anatomia & histologia , Estações do Ano
7.
Braz J Biol ; 76(3): 743-9, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27097082

RESUMO

Many aspects of sex change in reef fishes have been studied, including behavior and social organization. However, gonad histology remains the most robust way to identify sexual patterns in fishes. Some uncommon tissues remain poorly described, such as the accessory gonadal structures found in species from the Gobiidae family, which are rare in other bony fishes. This is the first report of the testicular gland in Gramma brasiliensis and for the Grammatidae family. Between April 2011 and February 2012 eighty specimens were collected during four dive campaigns on the Taipus de Fora reef (13°56'20"S 38°55'32"W), Bahia, Northeast Brazil, and their sex was determined. Thirteen per cent of the active-females and 90% of the active-males had testicular gland tissue in their ovotestis. This discovery led to additional research into the characteristics of the gland tissue and its relationship with gonadal maturation. Three patterns of testicular gland development were found in Brazilian basslet ovotestis. Both ova and sperm-producing gonad contained testicular gland tissue, and the appearance of this tissue seems to be the first modification of ovotestis tissue marking the beginning of the protogynous sex-change process in G. brasiliensis.


Assuntos
Adaptação Fisiológica/fisiologia , Organismos Hermafroditas/fisiologia , Perciformes/fisiologia , Testículo/fisiologia , Animais , Brasil , Feminino , Gônadas/fisiologia , Masculino
8.
Braz J Biol ; 75(4): 936-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26675910

RESUMO

New records for Lysmata grabhami (Gordon, 1935) in Brazilian waters are presented. Four adult individuals from coastal waters off the city of Vitória, Espírito Santo coast and one adult from Trindade Island were collected during scuba diving in depths between 20-40 meters. These two records represent the southernmost published finding of this species in the Atlantic and the record for Vitória, Espirito Santo is the first from Brazilian coastal waters.


Assuntos
Distribuição Animal , Decápodes/anatomia & histologia , Decápodes/fisiologia , Animais , Brasil
9.
Braz. j. biol ; 75(4): 936-939, Nov. 2015. graf
Artigo em Inglês | LILACS | ID: lil-768191

RESUMO

Abstract New records for Lysmata grabhami (Gordon, 1935) in Brazilian waters are presented. Four adult individuals from coastal waters off the city of Vitória, Espírito Santo coast and one adult from Trindade Island were collected during scuba diving in depths between 20-40 meters. These two records represent the southernmost published finding of this species in the Atlantic and the record for Vitória, Espirito Santo is the first from Brazilian coastal waters.


Resumo Novos registros de ocorrência de Lysmata grabhami (Gordon, 1935) em águas brasileiras são apresentados. Quatro indivíduos foram coletados próximo à costa da cidade de Vitória, Espírito Santo, e um na Ilha da Trindade, por mergulhadores autônomos em profundidades entre 20-40 metros. O presente registro é a ocorrência mais meridional conhecida para esta espécie no Atlântico e o registro em Vitória é o primeiro para águas costeiras brasileiras.


Assuntos
Animais , Distribuição Animal , Decápodes/anatomia & histologia , Decápodes/fisiologia , Brasil
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