For our guests and nature photography visitors enthusiastic for Insects and Arachnids, a popular spot to visit while in REGUA is the Onofre Cunha forest fragment. It is one of the largest lowland forest fragments extant in the area but grossly cut in two pieces by the Funchal tarmac road. It has been selectively logged, hunted and some areas have been degraded by surrounding farm field activities but nevertheless it still boasts many interesting, rare or hard to see species with some regularity (the opposite of reforested areas exhibiting much arthropod population fluctuations) and many new records over the years originated there.
So, no wonder that after 12 years of regularly visiting, screening and recent monitoring of butterflies in the Cunha fragment, the most localised and rare of South America’s Emperor Butterflies (genus Doxocopa) just showed up very quickly and displayed itself sun basking in a sunny trail spot during early morning just enough to be photographed. Doxocopa laurona is an endemic Atlantic Forest species known only from a few widely scattered localities from sea level to below around 900 m across south-east Brazil: Rio Doce valley (MG and ES states), Petropolis (type locality) and coastal hills in the lakes area around Saquarema and Cabo Frio (RJ), Antonina (PR) and Joinville (SC).
The photo depicts an unmistakable male of Doxocopa laurona which belongs to a group of four species where both sexes are mimetic of Adelpha Sister Butterflies (usually only Doxocopa females resemble Adelpha) with the males of 3 species bearing a peculiar purple-violet sheen under a certain opening wing angle. So, it is easy distinguished from males of the more common and widespread Doxocopa linda where both sexes are purple less. Curiously, this late species flies together over the entire tropical continental area, overlapping with the other 3 taxa featuring purple males which are curiously mutually exclusive taxa that do not overlap their flying areas. This is probably because the purple colours of the males are secondary sexual characters that help females in choosing the proper conspecific male thus avoiding hybridization between distinct species. So D. linda is the only species that flies together with others in this group and locally shares territory with D. laurona.
On the same day a female was spotted during the routine monitoring walk in the same trail and thought to be Doxocopa linda, but as it turned out, it now could be either this or a female of D. laurona because females are devoid of purple colours and are look very similar.