The hemispherical scale, Saissetia coffeae (Walker) (Hemiptera: Coccidae) is one of the most important
pest attacking olive trees in Egypt.
The aim of the present work is to study the biological studies of the
hemispherical scale, S. coffeae. Mean durations of the first instar were
15.5± 0 .85, 12.8 ± 0.63 and 9±0.76 days at 18, 24 and 30^oC,
respectively. Second instar lasted for 23.3±0.67, 20.6±0.52 and 16.9± 0.88
days, respectively. While third instar durations were 22.6± 0.70, 19.8±0.63 and
13.2± 0.79, respectively.  Incubation
periods were 21.4 ± 1.17, 14.4 ± 0.70 and 10.1 ± 0.88 days, respectively. The
generation time was 82.80±1.48, 67.6±1.26 and 49.2±2.10 days, respectively. As
a result the durations of the adult longevity were 6±0.67, 8.7±0.82 and 8.9 ±
0.74 days at 18, 24 and 30^oC, respectively.