Answer: sporocysts

AnswerCrossword Clue
sporocysts(in parasitic sporozoans) An encysted zygote in an invertebrate host
sporocystsA parasitic fluke in the initial stage of infection in a snail host, developed from a miracidium
sporocystsSPOROCYST, a rounded, thick-walled structure produced, as by protozoans, in the process of sporulation