Does a facultative precocious life cycle predispose the marine trematode Proctoeces cf. lintoni to inbreeding and genetic differentiation among host species?

- Whether a facultative precocious life cycle could influence local scale genetic structure was tested.
- We found no effect of life cycle variation on local scale genetic patterns among individual parasites or among host species.
- The very high genetic diversity suggests a very large population size of the marine trematode Proctoeces cf. lintoni.
- Limpets, clingfish have limited home ranges, promote parasite genetic structure among spatially separated local populations.