Study shows butterfly wings contain same toxin as sea snail

(Phys.org)—A team of Austrian researchers has found that Hebomoia glaucippe, known as the great orange tip butterfly, has a toxin in its wing tips that is identical to a toxin used by a predatory sea snail to kill prey. They write in their paper describing their finding, published in the Proceedings of the National Academy of Sciences, that it appears the toxin in butterfly wings is used as a means of defense rather than as a weapon.

The great orange tip butterfly belongs to the Pieridae family of White and Yellow butterflies and inhabits temperate Asian climates such as those found in the island nations of the Philippines, Indonesia and Malaysia. They are all white save for the upper half of their upper wings which are bright orange. They are the largest of the lepidopteran family.

In studying H. glaucippe the research team homogenized the wings and bodies of sample specimens allowing them to extract proteins found in them. In so doing, they discovered the presence of one, glacontryphan-M, a peptide toxin that had previously only been found in a species of sea snail: Conus marmoreus, more commonly known as the marble cone snail.

C. marmoreus injects toxic chemicals into its prey via a harpoon, paralyzing it, which allows for easy consumption. One of the toxic chemicals it uses is the same peptide the research team has found in the wingtips of H. glaucippe, leading to questions regarding the lineage of both species and if they perhaps evolved from a shared distant relative.

Great orange tip butterflies don't attack prey, thus the toxin in their wings is assumed to be a defensive mechanism designed to ward off a wide variety of predators that include: spiders, ants, mantes, green frogs, lizards, and birds. The researchers note that the presence of the toxin in the wings doesn't always work as planned however, as many of its predators eat the body and ignore the wings and some, such as geckos appear to be impervious to it effects altogether.

To answer questions about why the butterfly and snail share a toxin, the researchers plan to obtain more great orange tip samples from other environments and to test other species to see if they too share the toxin.