The host specificity and population dynamics of <i>Anguillicola crassus</i> in a number of paratenic hosts were investigated. Various freshwater fish species were sampled monthly (March 1990 to March 1991) from the Kolenhaven (Albertcanal, Genk, Belgium) and examined for L<sub>3</sub>-larvae of <i>Anguillicola crassus</i>. Sixteen species were found to be infected: all the physoclist species examined (<i>Gymnocephalus cernua, Lepomis gibbosus, Ictalurus nebulosus, Stizostedion lucioperca, Gasterosteus aculeatus, Oreochromis niloticus</i> and <i>Perca fluviatilis</i>) and those physostome species of which a sufficient number could be examined to detect the infection (<i>Gobio gobio, Leuciscus... |