Molecular phylogeny and macroevolution of Chaitophorinae aphids (Insecta: Hemiptera: Aphididae)

Chaitophorinae is a predominantly Northern Hemisphere aphid subfamily characterized by numerous setae on the body. Two constituent tribes are associated with different host plants, with Chaitophorini feeding on deciduous trees and shrubs and Siphini colonizing grasses. Based on data from multiple genes (COI, COII, Cytb and EF-1 alpha), geographical distribution and host association, this study investigated the phylogeny and macroevolution of Chaitophorinae using phylogenetic reconstruction, molecular dating, model-based ancestral area and character estimations and diversification rate calculation. Our results support the monophyly of Chaitophorinae and two tribes, indicate that Sipha and the two largest genera Chaitophorus and Periphyllus are not monophyletic, and suggest a need for a change in the taxonomic status of Lambersaphis, which was nested within Chaitophorus in the phylogenetic tree. We recovered an origin of Chaitophorinae on Acer plants from eastern Asia during the Late Cretaceous to early Palaeocene, followed by multiple dispersals into other areas that were responsible for its contemporary distribution. The origins of Siphini and Chaitophorus + Lambersaphis coincided with colonizations of novel host plants. An increase in diversification rate occurred within Chaitophorus in the Miocene and was associated with range expansion and switching onto new host plants, highlighting the roles of dispersal and host shift in aphid diversification.