Graffilla effects reared and wild clam populations in Italy, Spain, the United States, and France.[2]
References
^Schell, Stewart C. (October 1986). "Graffilla pugetensis n. sp. (order Neorhabdocoela: Graffillidae), a parasite in the pericardial cavity of the bent-nose clam, Macoma nasuta (Conrad, 1837)". The Journal of Parasitology. 72 (5): 748–754. doi:10.2307/3281468. JSTOR3281468.
^Paillard, C.; Maes, P.; Oubella, R. (January 1994). "Brown ring disease in clams". Annual Review of Fish Diseases. 4: 219–240. doi:10.1016/0959-8030(94)90030-2.