Molluscicidal effect of niclosamide ethanolamine salt powder - granula against Oncomelania hupensis / 中国血吸虫病防治杂志

Objective To evaluate the molluscicidal effect of niclosamide ethanolamine salt powder?granula(PG)against Oncomelania hupensis. Methods The molluscicidal experiment was carried out by the dusting method with niclosamide etha?nolamine salt 4%PG. The experiments were respectively done in the laboratory and the tidal flats wetlands. At the same time , the niclosamide ethanolamine salt 4%dustable powder(DP)was as the control group. The single blind method was used for the quality control. The corrected mortality and the median lethal concentration(LC50)were compared between PG and DP in the molluscicidal experiment of the laboratory. The corrected mortality and the reduced rate of snails’density were compared be?tween PG and DP in the tidal flats wetlands. Results The mortality rates of the snails were 96.67%and 100%respectively on 1 d after dusting 4.0 g/m2 of 4% PG and 2.0 g/m2 of 4% DP in the laboratory. The results showed that the mortality rates of the snails were higher with 4%DP than 4%PG in each dosage(t1 d=3.60,P0.05). Conclusions 4%PG has both the adsorption of powder and the penetrability of the granules. The molluscicidal effects of 4%PG and 4%DP are almost the same. However,the drift of the powder was still not effectively controlled. This problem need to be further studied.

Orbiniidae polychaetes (Polychaeta: Scolecida) from Coiba Island, eastern Pacific of Panama, with description of a new species

Santa Cruz and El Gambute, two mangrove systems with associated tidal flats, were sampled in Coiba National Park, Coiba Island, Pacific of Panama. At each site, two samplings were done at low, middle and high intertidal levels in February and November of 1997. A new orbiniid species were found: Orbinia oligopapillata n. sp. is characterized by having 15-16 thoracic chaetigers with four or five rows of uncini and up to three papilliform postchaetal processes on neuropodial lobes by the abdominal parapodia bearing flail-tipped neurochaetae, and by the presence on anterior-most abdominal chaetigers of interramal cirri and a low number of subpodial and stomach papillae. A specimen belonging to genus Leitoscoloplos Day, 1977 is described as "Leitoscoloplos sp.", characterized by the lateral pouches on its abdominal chaetigers, a unique case for the family because these brooding structures have only been previously cited in two species of Scoloplos. Naineris sp. is characterized by the number of its thoracic chaetigers, branchiae, uncini and bilobed abdominal neuropodia with protruding aciculae.

En el Parque Nacional de Coiba, costa pacífica de Panamá, hay manglares con playas asociadas. Estudiamos la fauna de dos poliquetos orbínidos de Santa Cruz y El Gambute. En cada playa se eligieron puntos de muestreo al nivel de marea baja, media y alta y cada uno se realizaron dos muestreos, en febrero y noviembre de 1997. Encontramos individuos no identificables con certeza y una especie nueva: Orbinia oligopapillata n. sp., la cual se caracteriza por tener 15-16 setígeros torácicos con cuatro o cinco filas de uncinos y hasta tres procesos postsetales papiliformes en los lóbulos neuropodiales, por los parápodos abdominales provistos de sedas en bayoneta y por la presencia en los setígeros abdominales anteriores de papilas estomacales en escaso número. Leitoscoloplos sp. se caracteriza por llevar bolsillos laterales en los setígeros abdominales, caracter único en el género y que en la familia solo ha sido citada en dos especies del género Scoloplos. Naineris sp. se caracteriza por el número de setígeros torácicos, sus branquias, sus uncinos y sus neuropodios abdominales, bilobulados y con la acícula sobresaliente.