An extensive survey for natural pathogens and parasites of mosquitoes as prospective biological control agents was carried out in Israel. Coelomomyces (Class, Chytridiomycetes; Order, Blastocladiales), a fungal genus of which all but a few members are specific to mosquitoes, was not known to be present in Israeli waters. Therefore, mosquito and copepod host-range tests were conducted with Coelomomyces psorophorae obtained from abroad, in order to test the desirability of introducing Coelomomyces as a contribution to mosquito control. Acanthocyclops viridis, a cosmopolitan copepod relatively common in Israel, was duly infected with Coelomomyces psorophorae. However, the infectivity of Israel's most common pest mosquitoes (Culex pipiens complex) proved low.
