McLaren, I.W., & Buchanan, G.A. 1973 Parasitism by Aphytis chrysomphali Mercet and A. melinus DeBach of California red scale, Aonidiella aurantii (Maskell), in relation to seasonal availability of suitable stages of the scale.. Australian Journal of Zoology. Melbourne 21: 111-117.

Notes: Positive correlation between the percentage of available stages in the host population and the efficiency of parasitism by the Aphytis; scarcity of suitable hosts at certain times of the year is thought to limit the efficiency of Aphytis by reducing the chances of the parasite to achieve its reproductive potential; parasitism by Aphytis, rather than variation in weather, is responsible for the considerable seasonal fluctuations in percentage of scales available for parasitism.