Ocorrência do bivalve exótico Mytilopsis leucophaeta (Conrad) (Mollusca, Bivalvia), no Brasil Occurrence of exotic bivalve Mytilopsis leucophaeta (Conrad) (Mollusca, Bivalvia), in Brazil

O molusco Mytilopsis leucophaeta (Conrad, 1831), natural da América do Norte, foi localizado no litoral de Pernambuco, Brasil, em 2004, trazido provavelmente por água de lastro de navios. Na região, sua distribuição atualmente abrange zonas estuarinas adjacentes ao Porto do Recife. Os organismos foram encontrados restritos à região entre-marés, formando agregados densos com até 176.800 ind./m².<br>The mussel Mytilopsis leucophaeta (Conrad, 1831) is native to North America. It was found at Pernambuco Coast, northeastern Brazil, in 2004, probably brought by ships' ballast water. The distribution of this species has been now spread to estuarial area near Recife Harbour. They showed a clumped distribution with a maximum of 176,800 ind./m² only in the intertidal zone

Gloquídio de Diplodon martensi (lhering) (Mollusca, Bivalvia, Hyriidae) e seu ciclo parasitário The glochidium of Diplodon martensi (lhering) (Mollusca, Bivalvia, Hyriidae) and its parasitic cycle

<abstract language="eng">Conchological and anatomical studies of the glochidium of Diplodon martensi (lhering, 1893) were performed on samples collected in a small river, tributary from the Caí River, that belong to the Jacuí River sub-basin in south-eastern Brazil. The parasitic development of the glochidium was observed in laboratory on a small cichlid fish Gymnogeophagus gymnogenys (Hensel, 1870)