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- Age and growth of the blue jack mackerel, Trachurus picturatus Bowdich, 1825 (Pisces: Teleostei) off Madeira archipelagoPublication . Vasconcelos, Joana; Alves, Adriana; Gouveia, Elisabete; Faria, GraçaBetween 1984 and 1986, 630 pairs of sagitta otoliths were collected to determine the age and growth of the blue jack mackerel, Trachurus picturatus from Madeiran waters. The oldest specimen in this study was nine years old and the largest was 46 cm of total length (TL). The parameters of the von Bertalanffy growth curve were estimated for the whole period studied for all fish (L∞=42.32 cm, k=0.161 year-1, t0= -2.563 year; r2=0.743) for males (L∞=39.57 cm, k=0.194 year-1, t0=-2.282 year; r2=0.722) and for females (L∞=49.78 cm, k=0.114 year-1, t0=-3.052 year; r2 = 0.747). There was no significant differences in mean lengths (t–test, p>0,05) and in the von Bertalanffy growth curves (F test, p>0,05) between sexes. The validity of otolith readings for estimating age and growth was supported by results from backcalculation method. No significant differences were found in the Bertalanffy growth curves between direct reading of otoliths and backcalculation. Growth parameters estimated from backcalculated sizes-at-age were: for both sexes, L∞=48.28 cm, k=0.135 year-1, t0=-2.898 year and r2=0.999; for males, L∞=44.79 cm, k=0.143 year-1, t0=-3.207 year, r2=0.999; and females, L∞=44.63 cm, k=0.163 year-1, t0=-2.430 year, r2=0.999. The relationship between length and weight was calculated for all fish (Wt=0.00764Lt3.05746; r2=0.951), for males (Wt=0.01271Lt2.90807; r2=0.915) and for females (Wt=0.00604Lt3.12613; r2=0.948).
- Aspectos bioecológicos de Hyperaspis pantherina Fürsch (Coleoptera: Coccinellidae) predador de Orthezia insignis Browne (Homoptera: Ortheziidae)Publication . Félix, A. P.; Vasconcelos, J.; Brazão, C. I.; Aguiar, A. M. Franquinho; Rocha, P.O coccinelídeo Hyperaspis pantherina Fursch, predador específico de Orthezia insignis Browne, foi importado do Quénia e está a ser criado em laboratório na Ilha da Madeira desde Julho de 2002. Os adultos obtidos largados em Jacarandá mimosifolia D. Don, planta ornamental presente em arruamentos e jardins da cidade do Funchal. No presente trabalho apresentam-se alguns aspectos bioecológicos deste predador obtidos no âmbito da sua criação laboratorial, através do acompanhamento do ciclo de vida de dois casais do coccinelídeo.