Abstract:

The flea beetles (Coleoptera: Chrysomelidae: Alticinae) are phytophagous specialists with great economic significance. This paper deals with the latest progress in their feeding habits and differentiation. Exact meaning of host specialization is explained in details, and up to 85% genera of Alticinae are specialized, despite their broad host range. It is generally believed that Alticinae and Galerucinae, the specialists, are of recent origin from Chrysomelinae accompanying feeding differentiation which is thought to be important in the process. There are several models to explain the occurrence of the phenomena of feeding differentiation, among which “cost of generalism hypothesis" gets more and more experimental support. The insects are more likely to switch to plants with similar plant chemicals to their native host plants, in the forms of host shift, host expansion and host race formation. Host plants differentiation accelerates sympatric speciation. The research will also contribute to the coevolution theory of insectplant interaction.

Key words: Flea beetle, host plants, host specialization, feeding differentiation, coevolution