Kigoma is a good-sized city, claiming over 200,000 residents, in Tanzania. However, the butterfly known as Graphium kigoma, the Kigoma Lady, does not go into town often. All the fun facts about it seem to be waiting to be discovered by Tanzanians who are willing to find these butterflies in the forests west of the actual city. They are sometimes seen on Mount Kilimanjaro; a tour group admits that few people come to Kilimanjaro and few of those are looking for butterflies, but those who do watch for butterflies will be rewarded.
Not all lists even include Graphium kigoma as a species. Before 1964 this butterfly was thought to be a subspecies of Graphium almansor or G. poggianus. Robert Herbert Carcasson convinced most, but not all, scientists that it's distinctive enough to be listed as a species.
Several sources that list, but don't have a page or photo for, Graphium kigoma observe that all the "Lady" Swallowtails seem very much alike anyway.
There aren't a lot of these butterflies and they're not seen often but, because they are so rare and obscure, nobody knows whether the species is threatened in any particular way. Given the rate at which final-instar caterpillars crunch up leaves, it's necessary that many large moths and butterflies be sparsely distributed.
Photo from Lepidoptera.eu. Any Tanzanian naturalist could become famous by posting the first photo of this species alive on the Internet.
This male may merely have been fading longer than the female above, or individuals may vary between shades of gray and shades of brown; nobody seems even willing to guess which.
In a dim light they seem designed to look like dots of light on the dead leaves on the forest floor. The Ladies generally are not highly toxic to predators, don't look much like anything that is, and benefit from camouflage. This may explain why they're so little known by humans. This seems to be one of the few Swallowtail species in which the males are not attracted to brackish water or garbage--even melon rinds. They may be strictly pollinators.
Tanzanians divide the year into dry and wet seasons rather than hot and cold ones, and observe that dry season specimens of Graphium kigoma are smaller and paler and have pointier fore wings than wet season specimens. This suggests a short life span with two or more generations in a year, but nobody knows for sure. Slight but consistent differences are also considered to identify two subspecies: Graphium kigoma kigoma and G.k. wranghami, or, for some experts, Graphium poggianus kigoma and G.p. wranghami.
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