Well the molecular clocks put the divergence back to about 100 Ma to 66 Ma years ago.
From Wikipedia:
Molecular clock estimates suggest that butterflies originated sometime in the Late Cretaceous, but only significantly diversified during the Cenozoic,[10][1] with one study suggesting a North American origin for the group.[1
Picked in vinegar and sugar or salt brine? Because vinegar and sugar is just an uncarbonated soda with less acid and more sugar.