ALARY POLYMORPHISM IN TRIATOMA-SPINOLAI AND ITS POSSIBLE RELATIONSHIPWITH DEMOGRAPHIC STRATEGY

Among collections of Triatoma spinolai from various sites in northern Chile, adults from coastal populations are invariably wingless, wherea s inland populations show balanced alary polymorphism between wingless females and males that are either wined or wingless. Laboratory cross es showed that male offspring from normal-winged parents were always w inged (88% long-winged) and those from long-winged male parents were a ll long-winged, The male offspring from wingless males always included winged males: 11/33 = 33%, of which 8/11 = 73% were long-winged. An X -linked mutation is proposed to inhibit wing development. Field studie s of population demography indicate that male alary polymorphism is ad vantageous in the desert environment of northern Chile.