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Bug of the Week is written by "The Bug Guy," Michael J. Raupp, Professor of Entomology at the University of Maryland.

Malachites on the hilltop - Siproeta stelenes


A beautiful Malachite butterfly rests in the vegetation.


Bug of the Week continues its holiday from mid-Atlantic cold and plunges through the lowland forests of Costa Rica near the biological station at Palo Verde. To flee a horde of ferocious mosquitoes that discovered us as we hiked along a lowland trail, we ascended a small limestone outcropping overlooking the beautiful Tempisque River. There along the ridge top, dozens of Malachite butterflies aggregated on the vegetation lining the trail.  The Malachite derives its name from a striking mineral containing copper carbonate that is prized for its rich green color.


Several Malachites like this one rested on vegetation lining a ridge-top in Palo Verde. 

The occurrence of unusually large numbers of Malachite butterflies in a small elevated area was likely an example of hilltopping, a behavior found in many animals including several species of butterflies. Hilltopping is believed to be a strategy used to concentrate members of the same species in a relatively small area to increase the probability of bumping into a potential mate. It may not be surprising that in many species males often dominate the crowd at these social gatherings. Regardless of why so many Malachites dotted the landscape, it was delightful to be in their remarkable presence.


Many kinds of flowers are sources of carbohydrates for long lived Malachites.

As we learned with the Morpho butterflies we met in last week’s episode, fermenting fruit is one of the favorite foods of adult butterflies, but certainly many nectar producing flowers are also on the menu. Fruits and flowers are rich sources of the carbohydrates required by adults of these active, long-lived species. Leaves of the green shrimp plant and Yerba Maravilla are food for the spiny black and orange caterpillars of the Malachite.

While normally found from Brazil through Central America to Mexico, the Malachite also occupies several islands in the West Indies and was introduced to southern Florida sometime in the 1960s, where it has established and is doing fine.


Look at that proboscis lapping up citrus juice!


The interesting references “Amazon Insects” by James Castner and “Territorial hilltopping behavior in three swallowtail butterflies (Lepidoptera, Papilionidae) in western Brazil” by Carlos Pinheiro were used to prepare this episode.

To learn more about Malachite butterflies, please visit the following web site: