RESUMEN
Thirty-six freshwater fish from Bung Borapet, a large reservoir, were examined for helminths in July 2005. The prevalence of infection was 19.44 (7/36) and the intensity was 4.67 (168/36) per fish. Seven fish were infected with 4 species of helminths: 1 trematode, Clinostomum philippinensis (metacercariae); 1 cestode, Senga chiangmaiensis; 1 acanthocephalan, Pallisentis sp and 1 nematode, Camallanus anabantis. An encysted metacercaria of Clinostomum philippinensis was found in the gills of Trichogaster microlepis. The present study is a new report of Clinostomum metacercariae in the second intermediate host, T. microlepsis, in Thailand. Future work should investigate the epidemiology of the metacercarial stage in the intermediate host and the adult in the experimental definitive host.