Host-induced morphological variability in adult Posthodiplostomum minimum (Digenea: Neodiplostomidae).

Posthodiplostomum minimum adults were collected from natural hosts at Lake Pátzcuaro, Michoacán, México and from experimentally infected hosts. Intraspecific variation was measured using principal component analysis (PCA). Morphological traits such as general body shape, size, and the specific location of certain distinctive organs and structures showed great variation among hosts as described by PCA. These results extend previous studies on host-induced variation in P. minimum in showing that some conservative traits such as vitelline follicle distribution in fore-and hindbody, could be used for an extensive and complete revision of the genus Posthodiplostomum.