Complex sentence: In order to complete its life cycle, "F. hepatica" requires an aquatic snail as an intermediate host such as "Lymnaea truncatula", in which the parasite can reproduce asexually.
Split into simpler sentences: In order to complete its life cycle, "F. hepatica" requires an intermediate host. Its intermediate host is a snail, such as "Lymnaea truncatula", in which the parasite can reproduce asexually.