[Blattabacterium in the fat body of the Maritime Territory relic roach, Cryptocercus relictus].

Rod-like symbiotic bacteria in the fat body of the cockroach Cryptocercus relictus have a thin cell wall of the Gram-positive type; the nucleoplasm in "diffuse". The septum connected with a massive mesosome is formed during cell division. The bacteria in the host cells are surrounded will several host membranes. For tens of millions of years. Cryptocercus relictus has been developing in the conditions of entire geographical isolation, but the morphology of its Blattabacterium is similar to that of the symbionts of other cockroaches examined. This gives evidence to the conservative nature of the cockroach--bacterial symbiosis.