Mimicry is a very widespread phenomenon in Nature, where some species imitate the morphological and chromatic patterns of others, benefiting from some kind of protection due to this similarity to the model. The later usually has some physical or biochemical characteristic that makes it ‘hated’ by predators. In the case of butterflies, it is usually the presence of toxic (most often alkaloids) and/or unpalatable substances in the body of the models.

In the Americas there is an endemic tribe of the Danainae subfamily of Nymphalidae: the Ithomiini butterflies comprising about 350 species – many of them popularly called ‘glasswings’ or ‘clearwings’ due to the transparency of much of the surface of their wings – where most participate in mimetic rings between themselves and with other lepidopterans, including the subfamily Heliconiinae and some diurnal moths.

In most cases. the chemical compounds involved in toxic or “bad tasting” (unpalatable) butterflies are incorporated during the larva stage from feeding on their food plants. In the case of glasswings the plants used by the larvae are partly Apocynaceae (a source shared with the Danaiini tribe) but the majority feed on Solanaceae, a botanical family which includes popular vegetables such as tomatoes, potatoes, eggplant and ‘jiló’. However, many species sequester these alkaloid compounds already in adulthood; especially the males which suck alkaloids from the flowers and roots of shrubs, lianas or weeds of the Asteraceae family or decaying dry leaves of Boraginaceae.

During the tour of one of the butterfly monitoring transects (a section of the Yellow Trail) recently cleared for maintenance, I was able to observe over the course of a week how groups of various species of glasswings congregated on the roots of an Eupatorium shrub (Asteraceae) – especially in the early morning and afternoon – as exemplified by the photo below. The species observed sequestering alkaloids from these exposed roots were the following: Episcada striposis, Episcada sylvo, Hypothiris ninonia daeta, Hypothiris euclea lapria, Ithomia agnosia zikani, Ithomia drymo and Pseudocada erruca.

© Jorge Bizarro

For some reason green is not a common or popular colour for neotropical butterflies. Contrary to other tropical regions in the Old World, there are a mere handful of greenish butterflies in the American Tropics (some hairtreaks like Cyanophrys, Evenus, Arcas, Erora,  the brush footed Nessaea and a few swallowtails) among them the very large malachite green and brown mimetic species with large squarish wings with scalloped margins. This butterfly is a perfect mimic of the heliconine (longwing butterflies) Philaethria wernickei and P. dido, from which it can be distinguished by the larger size, less elongated wings and the heavily serrated hindwing outer margin with 3 small knobbly tails.

It is a common species found over a vast area of the Americas from southern Texas, Florida and the West Indies into Bolivia, Argentina, Paraguay and south Brazil. Adults are species typical of open forest found from sea level to 1,500 metres in humid or seasonal disturbed forest habitat such as clearings, river banks, roads, edges, secondary growth and even orchards or gardens where many species of weedy or grassy Acanthaceae thrive (Blechum, Justicia, Ruellia). Adults are both attracted to flowers and rotten fruit, they often sun bask in lower foliage on trails, roads or gardens, and females patrol short stretches of this habitat looking for their host plants. The larvae are olive-black with pinkish and white tubercles, thus very reminiscent of toxic Parides and Battus swallowtail caterpillars. The pupae are pale lime-green with a few short spike-like spines.

This is the Eueides isabella dianassa, belonging to the Nymphalidae family, subfamily Heliconiinae. This species flies all year round, however is often seen on the drier months of winter.
This species has a short life cycle, about 2-3 months and often remains close to the host plant (passion fruit/passifloras) where larvae feed on their leaves. The female is slightly larger than the male and lays isolated eggs on the underside of the leaves. The larvae, known as caterpillars, feed on leaves by scraping the lower surface while they are small.

Eventually when they become larger, they gnaw the edges of the leaves. When they reach the fifth age (after changing ‘skin’ 4 times to continue growing after stretching) instead of changing the skin, they abandon the plant and look for other sheltered places (walls, windows, dry wood or tree trunks) where the pupa or chrysalis is formed, staying another 4 to 6 weeks until the adult butterfly emerges.

On a sunny winter afternoon, mating was recorded. The males performed an “8” shaped movement around the female releasing pheromones. The female, already receptive, had her motionless abdomen waiting for the male. There were 3 males flying around the female, but in this case, the female only chose one to mate.

Renowned Atlantic Forest bird and butterfly guide, Richard Raby visited REGUA over the Carnival season. His aim was to escape the drums and processions in his home beach town of Maricá which is only about one and a half hours drive from REGUA.

Richard organises tours to Rio de Janeiro and has followed the REGUA project for many years. He was impressed with the species seen on the lowland trails in the restored forests along the trails by the wetlands. He told us that he would normally only see some of these species within mature forested parks.

Walking around the wetlands was the perfect place for him to relax and enjoy the peace and serenity. Whilst with us Richard was able to find and photograph some interesting butterflies, a few of which are pictured here. This just reinforces our belief that our restoration efforts are really working!

Milkweed butterflies from the genus Danaus are an emblematic group due to their incredible migration routes, colouration, multi-trophic interactions and so many other interesting aspects of their life histories. The Monarch butterfly Danaus plexippus has been extensively studied in North America, and just recently the Southern Monarch Danaus erippus has been considered as a separate species from Danaus plexippus. Last week, Pedro Ferreira (an undergraduate student at the Federal University of Rio de Janeiro( UFRJ) and Daniela Rdrigues (Monarch project main researcher) have found eggs of both the southern monarch D. erippus and the Queen Butterfly D. gilippus at REGUA.

Both species use milkweed Asclepias curassavica as a host plant. Thanks to Jorge Bizarro and Sidenei, who have indicated nice spots with milkweeds and butterflies, as well as the planting of some milkweed in tha last winter, they were able to find both the Southern Monarch and the Queen Butterfly in the wetland area. We are interested in conducting some experiments on larval behaviour and adult cognition of both Danaus species. For the moment, the Southern Monarch seems to be commonly seen all through the year, and the Queen Butterfly is fairly easy to see at higher altitudes, like in Salinas where this photo was taken.