Description of a hepatopancreatic rickettsia-like organism in the redclaw crayfish Cherax quadricarinatus

Basophilic, Gram-negative, microcolonies of rickettsia-like organisms were observed in the hepatopancreatic tubule epithelium of 1 moribund Cherax quadricarinatus from a farm in north Queensland. The tissue tropism of the organism is distinct from the systemic rickettsia-like organism previously described from C. quadricarinatus. This paper briefly describes the histopathology, cytopathology and basic morphology of the hepatopancreatic rickettsia-like organism.