Abundancia e distribui o temporal de larvas de Pachyurus bonariensis Steindachner, 1879 (Perciformes, Sciaenidae), em uma ba赤a do pantanal matogrossense = Abundance and temporal distribution of larvae of Pachyurus bonariensis Steindachner, 1879 (Perciformes, Sciaenidae), in a bay of the matogrossense pantanal

作者：Miriam Santin; Andrea Bialetzki; Luciana Fugimoto Assakawa; Tatia Leika Taguti

来源：Acta Scientiarum - Biological Sciences, 2009.

• corvina
• Pachyurus bonariensis
• reprodu o
• larvas de peixes
• pantanal
• corvina
• Pachyurus bonariensis
• reproduction
• fish larvae
• pantanal

Com o objetivo de analisar a distribui o temporal de larvas de Pachyurus bonariensis e sua rela o com algumas vari芍veis ambientais, foram feitas coletas na ba赤a Sinh芍 Mariana, Mato Grosso, entre mar o/2000 e mar o/2004, 角s 16 e 22h. Simultaneamente, amostras de 芍gua foram obtidas para determinar temperatura da 芍gua, oxig那nio dissolvido, pH e condutividade el谷trica. As maiores densidades foram verificadas entre os meses de outubro e janeiro, sugerindo ser este o principal per赤odo de reprodu o da esp谷cie. No entanto, larvas em est芍gio de pr谷-flex o e flex o tamb谷m foram encontradas no inverno,possivelmente associadas 角s condi es favor芍veis para a reprodu o. Indiv赤duos de todos os est芍gios estiveram presentes, ou seja, 谷 prov芍vel que todo o ciclo de vida da esp谷cie ocorra dentro da ba赤a. A densidade de larvas mais desenvolvidas na superf赤cie foi maior 角 noite, enquanto as larvas iniciais foram encontradas na superf赤cie em ambos os hor芍rios, ou seja, o grau de desenvolvimento morfol車gico larval influencia no padr o de distribui o da esp谷cie na coluna de 芍gua. With the objective to analyze the temporary distribution of Pachyurus bonariensis larvae and its relationship with some environmental variable, collections were carried in the Sinh芍 Mariana bay, Mato Grosso State, between March/2000 and March/2004, at 4:00 p.m. and at 10:00 p.m. Simultaneously, water samples were obtained to determine temperature of the water, dissolved oxygen, pH and electricconductivity. The higher densities were verified between October and January, suggesting to be this the main period of species reproduction. However, larvae in preflexion and flexion stages were also found in the winter, possibly associated to the favorable conditions for the reproduction. Individuals of all stages were present, thus it is probable that the whole life cycle happens inside of the bay. The density of larvae more developed in the surface was higher at night, while the initial larvae were found in the surface in both schedules, thus the degree of larval morphologic development influences in the distribution pattern of the species in the column of water.