These conspicuous brick-red butterflies with shiny black stripes and a variable number of white dots belong in the subfamily Danainae of the Brush Footed butterflies (Nymphalidae). Most of the genera in this group fly in tropical Africa and Indo-Australasian regions, being mainly blackish, creamy and greenish-white. However, the genus Danaus features mostly large bright brick-red species in the Americas with a couple of exceptions in the Old World. They are long lived migratory butterflies with the Monarch being worldwide famous for its yearly massive migrations between Canada and central Mexico.
These butterflies are a popular model among researchers who study biochemical inset-plant relationships due to the easiness in rearing them under laboratory conditions in large numbers. Danaus species retain some of the toxic secondary chemical compounds of their food-plants which protect them from predators during their adult life span. Daniela has been researching these relations for decades going back to UNICAMP and the group that specializes in these insect-plant interactions there. Ever since she moved on to the UFRJ in Rio de Janeiro she continued her research in REGUA and our region where both Danaus erippus and D. gilippus (slightly smaller and with more white dots than previous) are common dwellers. Their larvae feed locally on Milkweed (Asclepias curassavica), a perennial weedy plant occurring in sunny areas along roads, trails and open field plantations. Recently, a new foreign species of Asclepias arrived in some coastal areas in Brazil raising some questions and she is now testing how well Danaus erippus larvae perform on it in terms of growth rate and survival.