Avian trypanosomes are vector-borne hemoparasites of birds and numerous (approximately 100) species of the Trypanosoma genus have been described worldwide. Their geographical range is vast, from hot tropical to very cold climates. The descriptions of species have been based both on morphological and molecular grounds, and frequently the assumption is made that each species of trypanosome is exclusive of its bird host. Thus quite probably we are far from knowing the real situation. It has been suggested that unlike what happens with mammals infected by trypanosomes, in birds these would not ...