[Parasitism in the oothecae of Periplaneta americana (Linnaeus)].

Parasitism present in others of Periplaneta americana in 3 municipalities of Havana City was observed, and it was detected that Tetrastichus hagenowii (Ratz.) attained significant levels of parasitism for an average value of 21.5% in the oothecae revised. Their presence in locations where different pesticides are used and their biological characteristics give them the probability of being an efficient bioregulator of cockroaches.