OVERVIEW

This is a photo of a forest mother-of-pearl butterfly (Protogoniomorpha parhassus) from the Central African Republic, showing the tip of a hindwing. Overall, the butterfly has a light greenish color. As shown in the photo, its back (topside) also has a pink sheen at certain angles.

PHOTOGRAPHS

Detail view.

SPECIMEN

PHOTOGRAPH DETAILS

ADDITIONAL INFORMATION

The forest mother-of-pearl is a common butterfly that lives mainly in the rainforests of Africa (3). It is found in at least 29 countries, stretching from Guinea in the west to Ethiopia in the east and South Africa in the south (1, 2). Males (as shown in the photos above) are smaller than females and have a pink/magenta-colored opalescent sheen on the topside of their wings (3, 4). (The females’ wings are more of a creamy-yellow color (3).) Like the alpine black swallowtail, this butterfly has two forms–one for the dry season and one for the wet season (2, 5). This phenomenon, called seasonal polyphenism, is driven by environmental factors and gives each generation specific advantages for the time of year and habitat in which they will live (5). Variation can be seen in wing color, for example, where some winter versions have darker colored wings that help them absorb sunlight and more quickly reach the temperatures needed for flight (6). Their summer counterparts may have lighter colored wings as there is a higher payoff for developing reproductive or other features (7). Wing pattern can also vary across forms, where some wet season butterflies develop more prominent eyespots while their dry season counterparts have few or no eyespots (6). Being more active, the wet season butterflies may benefit by using the eyespots to deflect predators (at a time when prey animals are more plentiful), while the dry season butterflies are more stationary and have a better chance at avoiding predators through camouflage (5, 6). Seasonal polyphenism is not uncommon among butterflies and the range of difference between forms varies (5). In some instances the difference is so large that the forms were once thought to be entirely different species (5). In the case of the forest mother-of-pearl butterfly above, there is some seasonal variation in the size of the eyespots (5). Photos of both sexes and forms can be found on pages 8 to 9 of this document.

REFERENCES

Copyright © by Aaron-Emile W. Osborn, all rights reserved.