Echinostoma miyagawai
Echinostoma miyagawai is a species of echinostome parasite that is found in Europe, Southeast Asia and Japan. It can use multiple aquatic snail species as first intermediate host, such as Planorbis planorbis, Anisus vortex, and Radix peregra. The definitive host species include the wild duck, the tufted duck, the domestic chicken, and the brown rat. In the definitive host it resides in the small intestine, cecum, and rectum. In Thailand and Laos E. miyagawai, is more common parasite of free-living ducks than E. revolutum. Taxonomy 

Genetic analysis has shown that the species can be subdivided into two different lineages; a Eurasian lineage and an Australian lineage. The latter includes individuals from Australia and the Americas. Genetic exchange within these lineages over such long distances is possible through distribution by birds. However, it has also been suggested that the Eurasian lineage might actually present a distinct species. Furthermore, Echinostoma miyagawai is a cryptic species and there is still debate about whether E. miyagawai and E. robustum should be considered as one species, or two separate species. The TkD1Int5 sequence implies two individual species, but the results from the mitochondrial genes cytochrome c oxidase, and NADH dehydrogenase are less clear. This debate is further complicated by the notion that hybridisation between the two species might occur. Hosts
According to the World Register of Marine Species, Echinostoma miyagawai has been seen in the following hosts:

Intermediate hosts
 Gyraulus centrifugops
 Anisus vortex
 Stagnicola corvus
 Gyraulus chinensis
 Ampullaceana balthica
 Stagnicola palustris
 Peregriana peregra
 Great pond snail
 Great ramshorn
 Planorbis planorbis
 Dybowski's frog
 Common frog

Primary hosts
 Falcated duck
 Mallard
 Tufted duck
 Ferruginous duck
 Rock dove
 Red junglefowl
 Pallas's gull
 Black-headed gull
 Golden hamster
 Brown rat
 Spotted dove
 Northern lapwing

References

Echinostomata
Animals described in 1932
Fauna of Indonesia
Fauna of Japan
Fauna of Spain
Fauna of Poland
Fauna of Bulgaria
Fauna of the Czech Republic