The purple scale,Lepidosaphes beckii(Newman), has been reduced from the 4th most important pest of Texas citrus to an incidental pest by the introduced parasite,Aphytis lepidosaphesCompere. The evidence of complete biological control is the scarcity of the purple scale during 1971–73 and the ability of the parasite to suppress the relatively small numbers of scales that increase following applications of carbaryl, sulfur, and azinphosmethyl.