This is a photo of a red flasher butterfly (Panacea prola) from Peru, showing the scales that cover the underside of the forewing.


Detail view.




Approximate Photo Location (Underside)


Magnification: 4X

Field of view: ~3/8” x 1/4” (9.0mm x 6.0mm)

Images in focus stack: 13


The photo above shows a larval form of the red flasher butterfly. Photo credit: Andreas Kay (Flickr, CC BY-NC-SA 2.0 (Edits: sizing)).

The red flasher (or prola beauty) butterfly is found in Panama, Colombia, Venezuela, Ecuador, the Guianas, and the Upper Amazon (Peru)(1, 2). The length of it’s life cycle, from egg through adult, is on the order of 30 to 55 days (2). (Photos of each stage can be found on page 75 of this document.) The female red flasher lays her eggs on plants in the genus Caryodendron (2, 3). The eggs are deposited on or near immature leaves, as the softer material is easier for the newly born larva to eat (2). The larva (or caterpillar) is the main feeding phase for butterflies (5). It is characterized by stages of growth called “instars;” a caterpillar advances to the next instar each time it molts (5). Most larva typically have three to five instars (5). The red flasher has six (2). After about 15 to 20 days, the mature red flasher larva transitions to the prepupa stage and loses some of its color, attaches to the plant or surface from which the pupa will hang, and becomes immobilized (2). By this time, the transition to the adult form has already begun (4). Larvas are born with clusters of cells, called “imaginal discs,” that are the genesis for a number of adult structures. Cell groups exist for the wings, eyes, legs, and others, and their growth accelerates during the final instar (4, 5, 6, 7). The adult legs, for example, begin to form inside the larval legs, the larval antenna grow to become the larger adult antennae (they are folded inside the larva’s head), and the compound eyes begin to grow next to the larval eyes (4, 5). At the end of larval/prepupal stage, the caterpillar molts for the final time, revealing the pupa. Inside the caterpillar releases enzymes that break down and dissolve many of its tissues into proteins (6, 7). The tracheal (breathing) system starts to increase in volume and becomes more complex, and the larval midgut (that processes plant tissue) changes its placement and transforms into the shorter adult gut (8). The nervous system and muscles are also reorganized, and the imaginal discs continue to rapidly grow into the adult forms (4, 5, 7). Red flasher butterflies emerge from the pupa (also called the chrysalis) after about 8 days, and adult males live about another week and females about a month (2). This longevity is fairly typical for adult butterflies, though some (like the Monarch) live much longer at six to seven months (5, 9).


1. Panacea Godman & Salvin, [1883]. (n.d.). Retrieved from the Finnish IT Center for Science.

2. Vasquez, J., Lamas, G., Couturier, G., & Mejia, K. (2012). Aspectos biologicos de Panacea prola amazonica (Fruhstorfer) (Lepidoptera: Nymphalidae), en la Amazonia Peruana. Folia Amazonica, 21(1–2), pp. 71–76. Retrieved from ResearchGate.

3. Hill, R. I., Penz, C. M., & DeVries, P., J. (2002). Phylogenetic analysis and review of panacea and batesia butterflies (Nymphalidae). Journal of the Lepidopterists’ Society, 56(4), pp. 199–215. Retrieved from ResearchGate.

4. Belth, J. (2013). Butterflies of Indiana: A field guide [The life of a butterfly]. Bloomington, IN: Indiana University Press. Retrieved from Google Books.

5. Scott, J. A. (1992). The butterflies of North America: A natural history and field guide. Stanford, CA: Stanford University Press. Retrieved from Google Books.

6. Yong, E. (2013, May 14). 3-D scans reveal caterpillars turning into butterflies. Retrieved from National Geographic.

7. Jabr, F. (2012, August 10). How does a caterpillar turn into a butterfly? Retrieved from Scientific American.

8. Lowe, T., Garwood, R. J., Simonsen, T. J., Bradley, R. S., & Withers, P. J. (2013). Metamorphosis revealed: Time-lapse three-dimensional imaging inside a living chrysalis. Journal of the Royal Society Interface, 10, 20130304. Retrieved from The Royal Society.

9. Opler, P. A. (1999). A field guide to western butterflies. New York: Houghton Mifflin Company. Retrieved from Google Books.

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