Phylogenetic analysis of mosquito Vtg genes. Phylogenetic analysis of mosquito vitellogenin gene sequences was conducted using Maximum Likelihood, Bayesian and Neighbor-joining methods; numbers at nodes indicate support values for each method (in that order). T37L-associated (putative ancestral) Vtg copies in different mosquito species are indicated by "*". Vtg gene of honey bee Apis mellifera (accession number AJ517411) was used as outgroup. Vtg gene accession numbers are AJ517411 for honey bee, AY691327 for AaVgC and the remainder are listed in Table 2.