First detection of an invertebrate iridovirus in the daphnid, Daphnia pulex.

Daphnia pulex from a small pond were infected by an iridescence virus. Infected daphnia differed from healthy ones due to the intense characteristic pink reflected iridescent color. Infected individuals collected in the field died in laboratory as a result of the iridoviral infection. Ultrastructural analysis using electron microscopy revealed highly abundant icosahedral virions in the cytoplasm of multiple types of tissue in the infected daphnids. The mean particle sizes were approximately 200 nm (n = 150) edge-to-edge and 185 nm point-to-point. Keywords: daphnia; Daphnia pulex; iridovirus; electron microscopy.