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AGOSTINHO, A.A.; BARBIERI, G.; VERANI, J.R.; AGOSTINHO, C.S. Ciclo reprodutivo e primeira maturação de Rhinelepis aspera (AGASSIZ 1829), (Teleostei - Loricariidae) no rio Paranapanema. Revista Unimar, Maringá, v.8, n.1, p.17-27, 1986. The natural reproductive cycle of armoured catfish Rhinelepis aspera is described with basis on the seasonal variation of gonadosomatic index values as well as the maturity stages. Specimens were collected in the Paranapanema River (22º38'S, 51º25'W) monthly from May, 1980 to May 1981. The spawing occurs essencially in January and February, when rainfalls are heavy, the days are long and the temperatures are high. The first sexual maturation males was observed at 24,0 cm and for females at 22,0 cm which correspond to 2,7 years for both sexes. O ciclo reprodutivo de Rhinelepis aspera é caracterizado com base nos valores médios mensais do índice gônado-somático e nas freqüências dos estádios de maturidade gonadal. As coletas foram realizadas no Rio Paranapanema (22º38'S, 51º25'W), no período de maio de 1980 a maio de 1981. O período de desova é prolongado, sendo mais acentuado nos meses de janeiro e fevereiro, quando as temperaturas são altas, os dias longos e as chuvas intensas. O tamanho da primeira maturação sexual é de 24,0 cm para os machos e 22,0 cm para as fêmeas. Esses comprimentos correspondem à idade de 2,7 anos, podendo-se concluir que a espécie se reproduz pela maturation of primeira vez após dois anos de idade, ou seja, entre o 2º e o 3º ano de vida. Abstract: The natural reproductive cycle of armoured catfish Rhinelepis aspera is described with basis on the seasonal variation of gonadosomatic index values as well as the maturity stages. Specimens were collected in the Paranapanema River (22º38'S, 51º25'W) monthly from May, 1980 to May 1981. The spawing occurs essencially in January and February, when rainfalls are heavy, the days are long and the temperatures are high. The first sexual maturation males was observed at 24,0 cm and for females at 22,0 cm which correspond to 2,7 years for both sexes.

AGOSTINHO, Angelo Antonio; BARBIERI, Geraldo; VERANI, José Roberto. Idade e crescimento do cascudo preto Rhinelepis aspera (Siluriformes, Loricariidae) no rio Paranapanema, bacia do rio Paraná. Revista Unimar, Maringá, v.13, n.2, p.259-272, 1991. Age and growth were estimated from counts of hyaline zones in the vertebrae of the armoured catfish Rhinelepis aspera. The annual cycle of the hyaline zones formation was determined by monthly variation of the length of specimens with the same number of hyaline zones and by the monthly frequency of marginal rings. The method to infer age was validated for age groups ranging from 3 to 9 years by these procedures. Data indicate that hyaline zones are formed essentially during April-May. The oldest fish examined was estimated to be 10 years old. The growth curve in Von Bertalanffy's growth equations was: males : Lt = 64,6 [1 - e-0,124.(t + 0,86)] females : Lt = 74,5 [1 - e-0,102.(t + 0,85)] The length-weight relation of males and females was different and has been described by the equations: males: Wt = 0,0153 . Lt2,986 (n = 689) females: Wt = 0,0137 . Lt3,018 (n=632) males + females: Wt = 0,0151 . Lt3,007 (n = 1.321) The estimated weights of male and female asymptotic measurements were 3894.1 g and 6105.0 g respectively. The reduced number of older specimens used in the adjustment of the growth curve may have produced a higher asymptotic measurement. Estimativas de idade e crescimento do cascudo preto, Rhinelepis aspera, foram feitas a partir de anéis de crescimento presentes nas vértebras. O ciclo anual de formação de anéis foi determinado pelo comprimento médio mensal de exemplares de mesmo número de anéis e através da freqüência mensal de anéis hialinos marginais. O método para atribuição da idade foi validado para as idades de 3 a 9 anos por estes procedimentos. Estes dados indicam que os anéis de crescimento são formados nos meses de abril-maio. O peixe mais velho examinado tinha 10 anos de idade. A curva de crescimento, ajustada pela expressão de von Bertalanffy resultou em: machos : Lt = 64,6 [1 - e-0,124.(t + 0,86)] fêmeas : Lt = 74,5 [1 - e-0,102.(t + 0,85)] A relação peso (Wt) / comprimento (Lt) mostrou diferenças significativas entre os sexos, podendo ser expressa como machos: Wt = 0,0153 . Lt2,986 (n = 689) fêmeas: Wt = 0,0137 . Lt3,018 (n=632) machos e fêmeas: Wt = 0,0151 . Lt3,007 (n = 1.321) Os pesos estimados nos comprimentos assintóticos de machos e fêmeas foram, respectivamente, 3894,1 g e 6105,0 g. O número reduzido de exemplares mais velhos utilizados no ajuste da curva de crescimento pode ter produzido uma superestimativa do comprimento assintótico. Abstract: Age and growth were estimated from counts of hyaline zones in the vertebrae of the armoured catfish Rhinelepis aspera. The annual cycle of the hyaline zones formation was determined by monthly variation of the length of specimens with the same number of hyaline zones and by the monthly frequency of marginal rings. The method to infer age was validated for age groups ranging from 3 to 9 years by these procedures. Data indicate that hyaline zones are formed essentially during April-May. The oldest fish examined was estimated to be 10 years old. The growth curve in Von Bertalanffy's growth equations was: males : Lt = 64,6 [1 - e-0,124.(t + 0,86)] females : Lt = 74,5 [1 - e-0,102.(t + 0,85)] The length-weight relation of males and females was different and has been described by the equations: males: Wt = 0,0153 . Lt2,986 (n = 689) females: Wt = 0,0137 . Lt3,018 (n=632) males + females: Wt = 0,0151 . Lt3,007 (n = 1.321) The estimated weights of male and female asymptotic measurements were 3894.1 g and 6105.0 g respectively. The reduced number of older specimens used in the adjustment of the growth curve may have produced a higher asymptotic measurement.

ORSI, Mário L.; AGOSTINHO, Angelo Antonio. Introdução de espécies de peixes por escapes acidentais de tanques de cultivo em rios da Bacia do Rio Paraná, Brasil. Revista Brasileira de Zoologia, Curitiba, v.16, n.2, p.557-560, 1999. Species composition and abundance of fishes that escaped from aquaculture facilities during catastrophic flooding in the Paranapanema and Tibagi rivers, in January, 1997 was estimated. In all, 1,292,000 adult individuals belonging to 11 species and 1 hybrid, were introduced into these rivers; only one species was native. The disasteris attributed to the illegal occupation of the river banks, and the non observance of standard measures designed to avoid escapement.