Thule was an old Roman name for the end of the world. Specifically it was imagined to be the north edge of the world, where everything was always frozen.. Graphium thule is a tropical butterfly but it lives in New Guinea, which must have seemed, to some early naturalists, as far from home as it was possible to go.
Photo by Imamthidayat, taken in August in New Guinea.
Although it has the wing structure of a Swallowtail, its color markings resemble some other butterflies that live in the same area. Each species grew up eating leaves that were toxic to warm-blooded animals in a different way, and gets some survival benefit from its resemblance to the others. More specifically, Graphium thule eats Aquifoliacene ilex as a caterpillar, Ideopsis juventa can eat several plants but favors Tylophora flexuosa, and Tirumala havata eats a variety of plants including Parsonsia and Hoya australis.
Graphium thule is not exactly common, but is less rare than its representation on the Internet might suggest, due to its confusibility. People don't want to post photos when they're not certain which butterfly they've photographed. Few people are familiar enough with Graphium thule, Ideopsis juventa, and Tirumala havata to be certain. Tirumala havata is the species of which a group migrated to New Zealand in 1995.
Partly as a result of this confusion, little is known about Graphium thule's life cycle.
Wallace called it a "form of Graphium macareus, but smaller"--with a wingspan of only 3.75 inches. Craven observed that most females he found looked just like the males, but some had much smaller light-colored patches on the hind wings. Individuals vary somewhat in wing patterns with some variations being common enough to have been named leuthe, goldiei, felixi, alfredi, and princeps. A description of these variations is available at
Apparently, as in so many Swallowtail species, males extract moisture from puddles, or even damp soil that remains as puddles dry up. They may be aware that each individual gains some safety from predators when they form large mixed-species puddle parties.
Photo by David Bishop.
There is still time for New Guineans to become famous by documenting the early stages of this butterfly's life.
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