A new iridovirus of two species of terrestrial isopods, Armadillidium vulgare and Porcellio scaber.

A new iridovirus, herein named isopod iridescent virus (IIV), was isolated from two species of terrestrial isopods in Berkeley, Calif. Infected individuals of Armadillidium vulgare and Porcellio scaber (Crustacea:Isopoda) appeared purple in color; in thin sections, hemocytes, nerve cells, and fat body cells contained cytoplasmic aggregations of virions. Isolated particles, 135 nm in diameter in negative stain, contained DNA had included at least 19 polypeptide components. The virus was transmitted per os and by injection to healthy isopods, and by injection to larvae of a coleopteran. IIV from the isopod hosts differed from Tipula iridescent virus (TIV) in buoyant density, molecular weights of major polypeptides, and serological reactions with antisera to IIV and TIV.