Abstract
The Colombian toads Bufo marinus, B. typhonius ockerdeni, B. guttatus and B. blombergi were infested with Tritrichomonas batrachorum. Samples of feces obtained directly from live toads and cultures made of the flagellates. Uninfected B. marinus were kept with individuals of B. typhonius ockerdeni harbouring small T. batrachorum. After 42 days all B. marinus were infested with T. batrachorum of the large strain, originally isolated from that host species. Ingestion of trophozoites and cysts is considered to be the normal route of entry. The trichomonads fit the original description of T. batrachorum and the difference in size is considered to be due to host adaptation. T. batrachorum has not yet been recorded for Colombia, and all toads except B. marinus are new hosts.
