Abstract: Microsatellite DNA is widely dispersed in eukaryotic genomes with the characters of high polymorphism, high abundance, codominance, selective neutrality, and easy manipulation. Therefore, it has been increasingly applied to studies of conservation genetics of endangered animals in recent years. The polymorphism of microsatellite DNA is so high that it can provide excellent resolution not only for kinship and mating system studies at the individual level, but also for genetic structure research at the population level. The DNA template needed for microsatellite analysis is very low and has no special demands, so that small samples obtained with noninvasive method and from old specimen can be analyzed effectively. Therefore, the approach not only makes investigation of endangered animals surviving in the wild more convenient and exact, but also can make use of the rare specimens preserved in museums to reveal important evolutionary history for some species. Furthermore, some microsatellite fragments′ sizes can be discriminated among related species, which makes it possible to identify species more conveniently with only fragment analysis. However, application of microsatellite DNA markers also has its own shortcomings, and appropriate molecular makers should be adopted for a given issue according to different research purposes.

Key words: aphids, species diversity, zoogeography, host plant, Hong Kong