PORTUGUES: E referida a eliminacao de cercarias do tipo Xifidiocercaria em exemplares de Lymnaea peregra (Muller, 1774), colhidos num tanque, em Monchique, Algarve. Os caracois encontravam-se parasitados numa taxa de 97 %, sendo trezentos e oitenta o numero medio de cercarias eliminadas por caracol, em vinte e quatro horas. Sao tambem apresentados alguns aspectos morfologicos e biologicos das formas larvares responsaveis por aquele parasitismo. | It was refered the emergence of cercariae, Xiphidiocercaria type, from samples of Lymnaea (Radix) peregra (Muller, 1774). These snails were collected in a pond, in Monchique (Algarve). On 115 specimens examined 97 % were parasitized. Over a period of 24 hours, 380 cercariae were liberated by snail. Several morphological and biological features of these worms were also presented.

The optimum temperature and exposure time necessary to obtain Probit 9(99.9968 % mortality) for third instar larvae of Anastrepha striata Schiner, when these are immersed in hot water, determined. Treatments were 39.0, 39.6 and 40.0 deg C for periods of 30 to 180 minutes at intervals of 30 min and 42.0 deg C for periods of 30 to 60 minutes at intervals of 10 min. The immersion times estimated to obtain Probit 9 were 154' 53", 137' 50", 124' 41" and 48' 00", respectively. The temperatures estimated to obtain Probit 9 from treatments for 90 and 120 min, were 41.53 and 39.67 deg C, respectively. These results allow to predict the feasibility of applying a quarantine heat treatment for fruits infested with A. striata, as well as to select the time and temperature most appropriate to treat sensitive fruits. | Se determino la temperatura y tiempo optimo de exposicion para obtener la Probita 9 (99.9968 % de mortalidad) para larvas de tercer instar de Anastrepha striata Schiner cuando se sumergen en forma directa en agua caliente. Los tratamientos fueron 39.0, 39.6 y 40.0 grados C por periodos de 30 a 180 minutos en intervalos de 30 min, y 42.0 grados C por periodos de 30 a 60 minutos en intervalos de 10 min. Los tiempos estimados para obtener la Probita 9 fueron 154' 53", 137' 50", 124' 41" y 48' 00", respectivamente. El analisis de los datos de mortalidad obtenidos con los tratamientos con duracion de 90 y 120 minutos estimo temperaturas de 41.53 y 39.67 grados C, respectivamente. Estos resultados permiten predecir la factibilidad de aplicar un tratamiento termico cuarentenario para frutos infestados por A. striata y ademas permiten elegir la dosis de tiempo y temperatura mas adecuada para frutos sensibles.