Virus-like particles in Perkinsus atlanticus (Apicomplexa, Perkinsidae)

Abstract

Virus-like particles (VLP) were observed in different phases of the in vitro zoosporulation of Perkinsus atlanticus (Apicomplexa, Perkinsidae) which parasitized the gill tissues of Ruditapes decussatus (Mollusca, Bivalvia). These VLP were represented by numerous electron-dense bodies (ca 125 nm diameter) not previously described in similar culture processes. The VLP were densely packed in a membrane-lined inclusion of isolated host-cell cytoplasm of parasitic origin. They were also found among prezoosporangia and zoosporangia of P. atlanticus , a species that causes recurrent mortalities in the clam R. decussatus . The ultrastructural organization of these VLP seems to represent a new and unclassified virus of P. atlanticus .