Grout, T.G., & Richards, G.I. 1989 The multiple cohort structure in populations of red scale, Aonidiella aurantii (Maskell) (Homoptera: Diaspididae), on citrus in South Africa.. Journal of the Entomological Society of Southern Africa 52(2): 277-283.

Notes: Abstract: Dual cohort structure appears to be the result of cyclic peaks in crawler emergence; dual cohort structures existed where red scale male flight peaks exceeded 1,000 males per card pheromone trap per week and parasitoids exerted little effect; a triple cohort structure occurred when red scale male flight peaks did not exceed 800 males per card pheromone trap per week, which was usually in the presence of Aphytis parasitoid species. Keywords: males; biological control.