Discovery of the Gall Generation of the Tropical Bamboo Aphid Pseudoregma carolinensis (Hemiptera) from Northern Thailand(Systematics, Morphology and Evolution)

Multiple-cavity galls of a cerataphidine species were found on the evergreen Styrax benzoides in Chiang Mai, northern Thailand. Comparison of mitochondrial DNA sequences between aphids from the galls and aphids of Pseudoregma carolinensis from bamboo revealed that the gall-forming aphids are of P. carolinensis. The colony sizes of mature galls were comparatively small, up to approximately 1, 500 individuals. The galls contained many pseudoscorpion-like 2nd-instar soldiers, which attacked an experimentally introduced moth larva, and which were observed to push globules of honeydew out of the subgall. The life cycle (holocycle) is probably annual, with some aphids remaining on bamboo throughout the year. The gall and alate morph are described.