A rhabdovirus was isolated in cell culture inoculated with tissue material from diseased grayling, T hymallus thymallus (L.), originating from a fish farm affected by a mortality episode in P oland. Diagnostics tests showed that the virus was not related to novirhabdoviruses known in E urope, nor to vesiculovirus‐like species, except p erch rhabdovirus ( PR hV) with which it shared moderate serological relations. However, RT ‐...