Fig. 8

Frequency distribution of pronotum width (at 0.2 mm intervals) in a P. angustipennis spadica and b S. esakii nymphs in each month. The collection month is shown in the upper right. Arrows and numbers (and “Final”) indicate mean pronotum width in each instar in laboratory rearing as determined by previous study (see Materials and Methods). Shaded areas indicate small nymphs for a P. angustipennis spadica: ≤ 4 mm in pronotum width; and b S. esakii: ≤ 3 mm.