Abstract
Two new trypanosomes, Trypanosoma yongi and Trypanosoma terbesar are detected in the blood of a giant toad, Bufo asper, from Peninsular Malaysia. The former species has a developed undulating membrane with 6 to 9 folds. The body length is 40.8-87.5 micrometers. The distance from the kinetoplast to the posterior edge of the round nucleus is 6.1-12.5 micrometers. The cytoplasm of the anterior part of the body along the well developed undulating membrane is often lightly stained with Giemsa. The latter species belongs to the so-called rotatorium-group having a fusiform nucleus, but the body size is very large compared with other species of the group, measuring 41.4-61.4 micrometers in length and 14.3-31.4 micrometers in width.
