The Gall Formation, Defenders and Life Cycle of the Subtropical Aphid Astegopteryx bambucifoliae (Homoptera)

Astegopteryx bambucifoliae (Hormaphidinae, Cerataphidini) migrates between Styrax suberifolia and bamboos in Taiwan. The following facts about its gall formation and gall inhabitants were obtained : 1) the banana-bundle-shaped gall of this species is initiated on the stem of a developing shoot of S. suberifolia in May ; 2) 1st-instar aphids of the 2nd generation play a defensive role, but, unlike those of Ceratovacuna nekoashi, they all have the opportunity to enter subgalls ; and 3) many 2nd-instar soldiers are produced in mature galls. Four out of 821 soldiers examined had the next instar cuticle developing inside. Such soldiers have hitherto been unknown among cerataphidines. The entire life cycle is briefly reviewed.