Phylogenetic Study Of Chinese Gall Aphids (Homoptera: Aphididae)

Chinese Gallnuts is the abnormal growth (gall) produced by some parasitic aphids on the leaves or stems of the host trees Rhus chinensis, R. potaninii or R.punjabensis var. sinica, a deciduous shrub of the family Anacardiaceae. It is an important resource insect and traditional export product of China. It can be used as a raw material of industrial without any substitute and has been extensively used in medicine, textile, chemical industry, food, environment protection, and agriculture purposes. Gall aphids belonged to the order Homoptera, superfamily Aphididae, family Pemphigidae, tribe Melaphidini, and are currently classified for 5 genera, 14 species. It is most difficult to identify them only by morphology because they often displayed complex life cycles, alternating sexual and asexual generations and host plant shift. The study of evolutionary relationships among gall aphids is vital not only for identify, protection, and utilization of the gallnut resource, but also for biogeography, co-evolution relationship between insects and plants.In this paper, 9 species (4 genera) representing of tribe Melaphidini from China were studied by means of numerical taxonomy, Cladistic analysis, RAPD analysis, and EF1α and COⅡ gene sequences analysis. Based upon these, the phylogenic relationships among gall aphids were researched and the results were performed by the form of dendrograms. The phylogeny hypothesis of Chinese gall aphids was presented base on this study and the previous morphological and ecological knowledge. The ancestors of Chinese gall aphids maybe diverged into two groups at first. One group feed on the first host tree Rhus chinensis and the other on the R. potaninii or R.punjabensis var. sinica. Then they evolved along their own respective direction. The former evolved to the genera Nurudea (N. ibofushi, N. shiraii, N. yanoniella) and Schlechtendalia (S. chinensis, S. peitan and N. ibofushi). The latter evolved to the genera Floraphis (F. meitanensis, F. choui), Meitanaphis (M elongallis, M. flavogallis and M. microgallis) and Kaburagia (K. rhusicola rhusicola, K.r. ovogallis, K.r. ovatirhusicola,...