First record of a reptile trypanosome isolated from Glossina pallidipes in Kenya.

Trypanosomes, isolated from the gut of a naturally infected Glossina pallidipes in Kiboko, Kenya, were grown in vitro. The cultured trypanosomes ("F4"-stock) showed a wide variety in morphological stages, not characteristic of the salivarian trypanosomes that are known to occur in the Kiboko area. Identification of the "F4"-stock was attempted by isoenzyme studies, infection of tsetse flies and of experimental animals. Electrophoretic isoenzyme patterns of the "F4"-organisms were developed for ten soluble enzymes and compared with those of 5 reference stocks of salivarian trypanosomes and 2 stocks of Trypanosoma theileri. For the T. theileri comparisons six enzymes were used. It was found that the "F4"-trypanosome clearly differed from the 3 salivarian species and from T. theileri. Experimental infection of laboratory bred Glossina m. morsitans showed that the "F4"-organisms developed in the posterior station of the alimentary tract and the cultured trypanosomes were infective to non-indigenous reptiles. This is believed to be the first record of the isolation and the isoenzyme characterisation of a non-salivarian reptile trypanosome from a naturally infected tsetse fly of the morsitans group (subgenus Glossina) in a savannah area in Africa.