Adults and immature (larval) specimens were frozen and preserved in RNAlater (Invitrogen, Carlsbad, CA). RNA extraction was performed using the PureLink RNA Mini Kit (Ambion, Carlsbad, CA). To obtain enough RNA from adult tissues we extracted material from a pool of six weevils for the head and abdomen samples. To extract RNA from immature tissues, between 50 to 100 first instar larvae were pooled, also maintaining the parental host plant and locality of origin. RNA concentration and quality were assessed using a NanoDrop 2000 spectrophotometer (ThermoFisher Scientific, Carlsbad, CA) and a Qubitâ„¢ 4 fluorometer (Invitrogen, Carlsbad, CA). mRNA sequencing using the standard Illumina Stranded mRNA prep